If you don't remember your password, you can reset it by entering your email address and clicking the Reset Password button. You will then receive an email that contains a secure link for resetting your password
If the address matches a valid account an email will be sent to __email__ with instructions for resetting your password
Colostrum is a rich source of nutritional and non-nutritional components and is recognized as essential to transfer passive immunity to newborn calves. Because of the individual and seasonal variability in colostrum yield and composition, maintaining an adequate supply of high-quality colostrum year-round remains a challenge for commercial dairy producers. In this narrative review, we described the individual, seasonal, and herd-level variability of colostrum production and summarized the association between individual animal factors such as parity, sex of the calf, calf birth weight, as well as indicators of the cow's metabolic status and the yield and composition of colostrum. Further, we reviewed the current knowledge on the influence of prepartum nutrition and management strategies on colostrum production. Research on the metabolizable energy and protein supplied in the prepartum diet as well as into the inclusion and source of vitamins, minerals, and feed additives suggests prepartum nutrition influences the yield, quality, and composition of colostrum. Furthermore, the prepartum environment and dry period length remain influential factors in the production of colostrum. However, additional research is needed to understand the mechanisms by which prepartum nutrition and management affects colostrum production. Lastly, time to colostrum harvest and oxytocin administration as well as the current knowledge on the effect of heat-treatment and colostrum storage strategies on colostral components were discussed. To conclude, we identify critical gaps in knowledge for future focus of investigation in colostrum research.
INTERPRETIVE SUMMARY Maintaining an adequate supply of high-quality colostrum is essential for rearing healthy calves but remains a challenge because of the individual and seasonal variability in colostrum production. This narrative review provides an overview of the variability in colostrum production and discusses the current knowledge on the effect of prepartum nutritional and managerial factors on colostrum production. Moreover, we discuss the effect of post-harvest practices on colostral components and identify critical gaps in knowledge for future focus of investigation.
INTRODUCTION
Mounting evidence supports the importance of colostrum for raising healthy calves (
Impact of 2 versus 1 colostrum meals on failure of transfer of passive immunity, pre-weaning morbidity and mortality, and performance of dairy calves in a large dairy herd.
). Because the cotyledonary synepitheliochorial bovine placenta inhibits transfer of maternal antibodies into fetal circulation, newborn dairy calves rely on timely ingestion of high-quality colostrum with low bacterial contamination to transfer passive immunity (TPI) as well as for nutrients and other bioactive components (
Invited Review: Effects of colostrum management on transfer of passive immunity and the potential role of colostral bioactive components on neonatal calf development and metabolism.
). Poor TPI in calves has been associated with lower average daily gain, a greater risk for preweaning morbidity and mortality, and a lower likelihood to reach first insemination and calving (
Feeding colostrum or a 1: 1 colostrum: milk mixture for 3 days postnatal increases small intestinal development and minimally influences plasma glucagon-like peptide-2 and serum insulin-like growth factor-1 concentrations in Holstein bull calves.
Impact of 2 versus 1 colostrum meals on failure of transfer of passive immunity, pre-weaning morbidity and mortality, and performance of dairy calves in a large dairy herd.
Effect of feeding colostrum at different volumes and subsequent number of transition milk feeds on the serum immunoglobulin G concentration and health status of dairy calves.
Effect of feeding colostrum at different volumes and subsequent number of transition milk feeds on the serum immunoglobulin G concentration and health status of dairy calves.
Extended colostrum feeding for 2 weeks improves growth performance and reduces the susceptibility to diarrhea and pneumonia in neonatal Holstein dairy calves.
Feeding colostrum or a 1: 1 colostrum: milk mixture for 3 days postnatal increases small intestinal development and minimally influences plasma glucagon-like peptide-2 and serum insulin-like growth factor-1 concentrations in Holstein bull calves.
Impact of 2 versus 1 colostrum meals on failure of transfer of passive immunity, pre-weaning morbidity and mortality, and performance of dairy calves in a large dairy herd.
) and prompted investigations to discover animal, environmental, nutritional, and managerial factors that influence the yield as well as IgG and component concentrations of colostrum. Further, dairy producers put forth equipment and labor resources required to harvest, store, reduce contamination, and feed high-quality colostrum. As such, this narrative review will describe the variability in colostrum production, discuss prepartum nutritional and management strategies as well as post-harvest practices associated with the production of colostrum and the preservation of colostral components, and identify knowledge gaps to direct future focus of investigation. The keywords “colostrum” and “cow” as well as other relevant keywords were used to identify literature that pertained to each variable discussed in this narrative review. Additional references were identified through citation mining. Unless otherwise stated, we refer to colostrum as the first milking only and to data from Holstein dairy cattle.
) exhibit seasonality. Colostrum yield was greatest in June (6.6 kg) and decreased to its lowest average yield of 1.3 kg in December in multiparous Jersey cows from a single dairy located in Texas, United States (
). In a study conducted in Germany, average colostrum yield from primiparous Holstein cows was greatest in April (4.1 ± 0.3 kg) and lowest during November (3.2 ± 0.3 kg) and average colostrum yield from multiparous cows peaked in May (5.5 ± 0.3 kg) and was lowest in October (3.8 ± 0.3 kg), respectively (
). Seasonality was also observed for other colostral components in samples collected in Northern Greece with greatest concentrations of fat in the spring (March–May), protein in the fall (September–November) and winter (December–February), and lactose in the fall, winter, and spring (
) and these associations might be related to changes in light as well as temperature and humidity exposure (discussed below). Although the inverse seasonal relationship between yield and IgG concentration has been hypothesized to be influenced by IgG dilution (
Effect of dry period dietary energy level in dairy cattle on volume, concentrations of immunoglobulin G, insulin, and fatty acid composition of colostrum.
Evaluation of factors associated with immunoglobulin G, fat, protein, and lactose concentrations in bovine colostrum and colostrum management practices in grassland-based dairy systems in Northern Ireland.
). Yet, when considering the amount of colostrum needed to feed a calf 2 colostrum meals (for example 3–4 L at first feeding; 2 L at second feeding), 60.0 and 65.3% of Holstein cows failed to produce ≥ 6 L of first-milking colostrum (
Evaluation of factors associated with immunoglobulin G, fat, protein, and lactose concentrations in bovine colostrum and colostrum management practices in grassland-based dairy systems in Northern Ireland.
Preweaned heifer management on US dairy operations: Part II. Factors associated with colostrum quality and passive transfer status of dairy heifer calves.
reported that 7.7 to 32.7 and 21.5%, respectively of cows produced poor-quality colostrum. In addition, important nutritional components for the calf including colostral fat [mean (SD) [Quartile 1, Quartile 3]; 6.4 (3.3) [2.5, 10.9] %], protein [17.8 (4.0) [12.7, 22.7] %], and lactose [2.15 (0.73) [1.2, 3.1] %] vary by cow (
Researchers investigating factors that affect colostrum yield and quality have mostly used observational data to uncover individual animal factors such as parity (
Evaluation of factors associated with immunoglobulin G, fat, protein, and lactose concentrations in bovine colostrum and colostrum management practices in grassland-based dairy systems in Northern Ireland.
Oligosaccharide concentrations in colostrum, transition milk, and mature milk of primi-and multiparous Holstein cows during the first week of lactation.
Evaluation of factors associated with immunoglobulin G, fat, protein, and lactose concentrations in bovine colostrum and colostrum management practices in grassland-based dairy systems in Northern Ireland.
) that commonly arise as associated with colostrum production. Within common dairy breeds, Jersey cows produced colostrum with the highest quality but experience periods of low colostrum supply specifically during the fall and winter months (
). Multiparous cows produced a greater volume of colostrum with higher IgG as well as protein concentrations while fat concentration was lower compared with primiparous cows (
Evaluation of factors associated with immunoglobulin G, fat, protein, and lactose concentrations in bovine colostrum and colostrum management practices in grassland-based dairy systems in Northern Ireland.
). Other variables from selected studies such as characteristics of the previous lactation or calf as well as the heritability of colostrum production are summarized in Table 1. Recently, authors have associated carrying a heifer calf as well as having a stillbirth with a lower colostrum yield in both Holstein and Jersey cattle (
). Circulating concentrations of placental lactogen during gestation has been positively associated with calf birth weight and milk production in the subsequent lactation (
Plasma bovine placental lactogen concentration throughout pregnancy in the cow; relationship to stage of pregnancy, fetal mass, number and postpartum milk yield.
). We hypothesize that endocrine signals during late gestation might contribute to the association between calf related variables (sex, birth weight, and stillbirth) and colostrum yield.
Table 1Previous lactation and calf characteristics as well as heritability associated with colostrum yield and quality
Short = 263–273, normal = 274–282, long = 283–293.
Short
Referent
Referent
Normal
↑
ND
Long
↑
ND
Angulo et al., 2015
Calf sex
Female
Referent
Referent
Male
↓
↑
Gavin et al., 2018
Calf sex
Twins
Referent
Referent
Female
↓
↑
Male
ND
↑
Kessler et al., 2020b
Calf sex
Not associated
Not associated
Poindexter, 2021
Calf sex
—
Female
Referent
Male
↑
Twins
↑
Borchardt et al., 2022
Calf sex
Not associated
Female
Referent
Male
↑
Twins
↑
Westhoff et al., 2023b
Calf sex
Female
Referent
Referent
Male
↑
↑
Twins
↑
ND
Karl and Staufenbiel, 2016, 2017
Stillbirth
Alive
Referent
Referent
Dead
↓
↓
Borchardt et al., 2022
Stillbirth
Not associated
Alive
Referent
Dead
↓
Westhoff et al., 2023b
Stillbirth
Alive
Referent
Referent
Dead
↓
↓
Conneely et al., 2013
Calf birth weight
↑
Not associated
Karl and Staufenbiel, 2016, 2017
Calf birth weight
↑
Not associated
Kessler et al., 2020b
Calf birth weight
Not associated
↓
Soufleri et al., 2019
Heritability
Not associated
↑
Costa et al., 2021b
Heritability
—
↑
Arrows indicate a positive or negative association with the variable relative to the referent when variable was categorized. Not associated = P > 0.05, nd = no difference from referent group (P > 0.05), dash = not reported.
1 Short = 257–269, normal = 270–280, long = 281–293.
2 Short = 263–273, normal = 274–282, long = 283–293.
Other variables such as gestation length, previous lactation length, and milk yield in the current or previous lactation resulted in mixed associations with colostrum production (
Pattern of milk yield and immunoglobulin concentration and factors associated with colostrum quality at the quarter level in dairy cows after parturition.
) and might be the result of differences in data collection, statistical analysis, or indicate the lack of a cause-effect relationship. Colostrum quality and composition appear to have low to moderate heritability (
The concentrations of immunoglobulins in bovine colostrum determined by the gold standard method are genetically correlated with their near-infrared prediction.
observed a positive association between colostrum yield and hypocalcemia when circulating calcium was measured at 1 DIM. Further, it was recently revealed that production of ≥6 L of colostrum was associated with an elevated prepartum β-hydroxybutyrate concentration and antioxidant potential as well as a lower cholesterol concentration and oxidant status index in Holstein dairy cows (
). Elevated colostral IgG concentration or Brix % was associated with higher prepartum serum albumin and glucose concentrations as well as a lower calcium concentration and glutamate dehydrogenase activity, as well as urinary net acid base excretion (
Factors influencing the immunoglobulin concentration in the first colostrum in Holstein-Friesian dairy cows and their relationship to the postpartum calcium concentration in blood and colostrum.
Tierarztl. Prax. Ausg. G Grosstiere Nutztiere.2017; 45 (29099901): 331-341
) and for every one liter increase in colostrum yield above the mean of 5.43 L, cows had a 1.1 (1.0–1.1) greater odds of hyperketonemia when evaluated between 7 and 14 DIM (
). Further, a 10.1–15.0% prevalence of hyperketonemia, at the herd level, during the early postpartum period (3–14 DIM) was associated with a greater colostrum yield (
). While these data are suggestive of a relationship between maternal metabolism and colostrum production in Holstein dairy cattle, the causality as well as the interactions between management, nutrition, and metabolism in respect to colostrogenesis remain unknown.
Herd-Level Variability
Herd-level differences in colostrum yield and composition within a geographic region (
) suggest variables beyond season of calving and individual animal factors influence colostrum synthesis. Annual median (Q1, Q3) colostrum yield and mean (SD) Brix % ranged from 3.7 (2.6, 5.3) to 7.7 (6.0, 8.6) kg and 22.0 (2.7) to 28.4 (5.1) % on 18 Holstein dairy farms (
). Although less than the intra-herd variability, inter-herd coefficient of variation was 35% for colostrum yield and between 6 and 22% for colostrum components (
) suggesting farm management, prepartum nutrition, or environmental conditions influence colostrum synthesis. Recent insights into the influence of dry period management (
), emphasize the potential to alter colostrum synthesis. However, because of the individuality and seasonality of colostrum production as well as the lack of complete knowledge on the metabolic and endocrine signals that regulate colostrum synthesis (
), a lack of understanding of mechanisms underlying colostrogenesis have largely limited our ability to explain the aforementioned differences in colostrum yield or composition. As such, our success in the ability to employ on-farm management and nutritional strategies to improve colostrum yield and composition has been minimal thus far and highlights the need for mechanistic studies to fill this important knowledge gap.
PREPARTUM NUTRITIONAL AND MANAGEMENT STRATEGIES
Prepartum Nutrition
Prepartum nutritional strategies are often evaluated by their effect on postpartum health and productivity. However, with the growing interest in and utility for colostrum (
), researchers have recently started to simultaneously evaluate the effect of these nutritional strategies on colostrum production. We encourage consideration of colostrum outcomes in these types of studies as future meta-analyses can be conducted to provide clarification of effect sizes and directions where there is currently no consensus.
Dietary energy
For a comprehensive review of the current knowledge on the effect of prepartum intake of carbohydrates, fat, and protein on colostrum production, we direct the reader to
Effect of dry period dietary energy level in dairy cattle on volume, concentrations of immunoglobulin G, insulin, and fatty acid composition of colostrum.
Effect of dry period dietary energy level in dairy cattle on volume, concentrations of immunoglobulin G, insulin, and fatty acid composition of colostrum.
Transition diet starch content impacts colostrum and transition milk composition and immunoglobulin G and insulin concentrations in Holstein dairy cattle.
). Inclusion of fat in the prepartum diet did not affect yield or component concentrations of colostrum and the effect of fat supplementation on IgG concentration remains mixed (
Effect of supplementing calcium salts of n-3 and n-6 fatty acid to pregnant nonlactating cows on colostrum composition, milk yield, and reproductive performance of dairy cows.
The Blood Immune Cell Count, Immunoglobulin, Inflammatory Factor, and Milk Trace Element in Transition Cows and Calves Were Altered by Increasing the Dietary n-3 or n-6 Polyunsaturated Fatty Acid Levels.
Colostrum yield from multiparous cows did not differ when shifting the prepartum metabolizable protein (MP) supply from 744 to 976 or 849 to 1,200 to 1,387 g of estimated MP/d (
Effects of shortening the close-up period length coupled with increased supply of metabolizable protein on performance and metabolic status of multiparous Holstein cows.
Colostrum production, calf birth weight, and postpartum ovarian follicular activity of dairy cows fed restricted diet with different protein levels during the prepartum period.
did not observe an effect of MP level, DMI, or the interaction on colostrum yield, IgG, or component concentrations. Similarly, the level of crude protein fed prepartum (
Effect of Various Levels of Dietary Protein in Transition Period on Colostrum Quality and Serum Immunoglobulin Concentration in Holstein Cows and their Newborn Calves.
) did not affect colostrum composition. However, we recently observed a tendency for an interaction between MP level fed prepartum and parity group such that cows entering parity 2 tended to produce more colostrum (9.4 ± 0.9 vs. 7.2 ± 0.9 kg) when fed an elevated level of MP (1,606 vs. 1,180 g of estimated MP/d) but colostrum yield from parity ≥ 3 cows was not affected by MP supply (5.1 ± 1.0 vs. 6.4 ± 1.0 kg; Westhoff et al., personal communication), respectively. Further, increasing the MP supply during the far-off (1,203 vs. 846 g of estimated MP/d) and close-up (1,631 vs. 1,258 g of estimated MP/d) periods resulted in a treatment x parity interaction for IgG concentration such that cows entering parity 2 fed an elevated MP supply had a greater IgG concentration (61.3 ± 2.3 vs. 55.2 ± 2.8 g/L) compared with parity 2 cows fed a lower MP supply, but MP supply did not affect IgG concentration in parity ≥ 3 cows (58.4 ± 3.0 vs. 56.8 ± 2.9 g/L;
The effect of maternal supply of rumen-protected protein to Holstein Friesian cows during the dry period on the transfer of passive immunity and colostral microbial composition.
), respectively. Although nulliparous heifers were not included in the 2 aforementioned studies, it remains plausible that younger cows might benefit from an additional MP supply to support mammary epithelial cell turnover during the dry period; however, the mechanism responsible as well as the validity of the treatment x parity interaction remain uncertain. Because of limited data as well as the aforementioned interaction, the effect of prepartum MP supply on colostrum production should be further investigated with inclusion of nulliparous heifers.
Hypocalcemia prevention strategies
Prepartum dietary strategies to mitigate hypocalcemia, including feeding a zeolite or manipulating the dietary calcium or cation anion difference (DCAD), alter prepartum DMI and circulating mineral concentrations (
Effects of feeding synthetic zeolite A during the prepartum period on serum mineral concentration, oxidant status, and performance of multiparous Holstein cows.
), disruptions in prepartum mineral metabolism or nutrient intake have potential to interfere with colostrogenesis. When feeding a diet including a zeolite at 500 g/d, colostrum yield (5.8 ± 0.8 vs. 7.3 ± 0.8 kg) and IgG concentrations (83.4 ± 4.8 vs. 76.3 ± 4.8 g/L) did not differ in the treatment compared with the control diet, respectively (
Effects of feeding synthetic zeolite A during the prepartum period on serum mineral concentration, oxidant status, and performance of multiparous Holstein cows.
Blood mineral and gas concentrations of calves born to cows fed prepartum diets differing in dietary cation-anion difference and calcium concentration.
Impact of a ration negative in dietary cation–anion difference and varying calcium supply fed before calving on colostrum quality of the dams and health status and growth performance of the calves.
Blood mineral and gas concentrations of calves born to cows fed prepartum diets differing in dietary cation-anion difference and calcium concentration.
Impact of a ration negative in dietary cation–anion difference and varying calcium supply fed before calving on colostrum quality of the dams and health status and growth performance of the calves.
), the complexity of calcium homeostasis, including the effect of 25-hydroxyvitamin D3 (discussed below), the role of the different widely used dietary hypocalcemia prevention strategies, and serotonin's negative association with colostrum yield (
observed that feeding 3 mg of calcidiol (25-hydroxyvitamin D3) tended to increase colostrum yield (7.8 ± 0.8 vs. 6.0 ± 0.8 kg) compared with cows fed cholecalciferol (vitamin D3), respectively. Further, when fed in combination with a positive DCAD diet, calcidiol also tended to increase concentrations of fat, protein, and total solids; however, feeding calcidiol did not result in altered colostral fat, protein, or total solids concentrations when cows were fed a diet with a negative DCAD (
). Additional data supported a trend for increased colostrum yield without an effect on colostrum components when cows were fed negative DCAD diets and cholecalciferol was replaced with calcidiol at either 1 or 3 mg/d (
Effects of feeding 25-hydroxyvitamin D3 with an acidogenic diet during the prepartum period in dairy cows: Mineral metabolism, energy balance, and lactation performance of Holstein dairy cows.
hypothesized calcidiol might have direct effects on epithelial cell proliferation through hormonal control or calcium and substrate availability. Colostrum IgG concentration was not affected by source of vitamin D in a study by
). Because of the interaction between DCAD and source of vitamin D on colostral components and the inconsistent results on IgG concentration when replacing cholecalciferol with calcidiol, further research is needed to determine the mechanism of action as well as increase the external validity of previous findings.
In addition to vitamin D, researchers have explored the source and inclusion of dietary minerals and vitamins on colostrum production. Because of limited placental transfer, certain colostral mineral and vitamin concentrations have also been considered as an important source for the newborn calf (
Effect of organic zinc, manganese, copper, and selenium chelates on colostrum production and reproductive and lameness indices in adequately supplemented Holstein cows.
Effects of replacing inorganic salts of trace minerals with organic trace minerals in the diet of prepartum cows on quality of colostrum and immunity of newborn calves.
Selenium biofortified alfalfa hay fed in low quantities improves selenium status and glutathione peroxidase activity in transition dairy cows and their calves.
Effects of replacing inorganic salts of trace minerals with organic trace minerals in the diet of prepartum cows on quality of colostrum and immunity of newborn calves.
). Although dietary supplementation of 0.2 ppm Se with 70 IU/kg vitamin E in combination with an injection of 50 mg Se and 300 IU vitamin E at 21 d before expected calving increased colostrum concentrations of α-tocopherol (
). Similarly, maternal supplementation of 700 to 800 mg/d of β-carotene did not affect colostrum yield or concentrations of IgG, retinol, α-tocopherol, or components and yielded mixed results on colostral β-carotene concentrations (
Supplementation of nicotinic acid to prepartum Holstein cows increases colostral immunoglobulin G, excretion of urinary purine derivatives, and feed efficiency in calves.
Combined biotin, folic acid, and vitamin B12 supplementation given during the transition period to dairy cows: Part II. Effects on energy balance and fatty acid composition of colostrum and milk.
A limited number of feed additives have been investigated for their effect on colostrum production and results have been mixed or inconsistent. Inclusion of magnesium butyrate supplemented at 105 g/d increased colostrum yield and total IgG mass but IgG concentration and colostral components were not affected (
reported a 2.9 ± 0.8 and 2.5 ± 0.8 kg increase in yield, respectively. In another study where cows were supplemented either with 0, 15, or 22 g/d of choline ions, colostrum yield was only different in the 15 g/d group, showing an increase from 3.4 (2.2–5.1) kg in control to 4.4 (2.8–6.7) kg or 5.4 (3.5–7.9) kg in cows fed 15 g/d of 2 choline products, respectively (
did not observe an effect on colostrum yield when supplementing 12.9 g/d of choline ions. Moreover, in a field study consisting of 21 prepartum pens (n = 2,171 cows), colostrum yield as well as IgG and component concentrations were not affected by choline supplementation at 12.9 g/d (
The impact of direct-fed microbials and enzymes on the health and performance of dairy cows with emphasis on colostrum quality and serum immunoglobulin concentrations in calves.
J. Anim. Physiol. Anim. Nutr. (Berl.).2018; 102 (29030887): e641-e652
The impact of direct-fed microbials and enzymes on the health and performance of dairy cows with emphasis on colostrum quality and serum immunoglobulin concentrations in calves.
J. Anim. Physiol. Anim. Nutr. (Berl.).2018; 102 (29030887): e641-e652
). The influence of feed additives and supplementation requires further consideration and replication of studies before conclusions can be drawn for on-farm use.
Prepartum Management
Prepartum environment
The seasonality of colostrum production, as described above, is confounded by changes in environmental conditions including exposure to light as well as heat exposure, measured as temperature-humidity index (THI). Authors have associated THI or photoperiod with colostrum yield (
Preweaned heifer management on US dairy operations: Part II. Factors associated with colostrum quality and passive transfer status of dairy heifer calves.
Photoperiod and Temperature-Humidity Index during the Dry-Period Impact Colostrum and Milk Production in Dairy Cattle. in Department of Animal Sciences.
). When THI 7-d before calving and light intensity 14-d before calving were categorized, colostrum yield from multiparous Holstein cows increased as THI and light intensity categories increased (
reported a positive correlation between colostrum yield from Jersey cows and photoperiod as well as maximum weekly THI. Nevertheless, the lack of studies considering photoperiod and THI independent of one another in controlled settings makes it challenging to determine if a causal relationship exists. In a study by
Photoperiod and Temperature-Humidity Index during the Dry-Period Impact Colostrum and Milk Production in Dairy Cattle. in Department of Animal Sciences.
, colostrum yield, Brix %, and IgG concentration from Holstein and Jersey cows did not differ when cows were managed for a short or long-day photoperiod (8 vs. 16 h of light/d). Similarly, increasing photoperiod from 8 to 16 h of light/d for the entire dry period did not affect colostrum yield and IgG concentration (
). Although more data are needed to determine if increased light exposure during the dry period can affect colostrum production, short day light exposure (8 h/d) during the dry period remains the optimal lighting program during the dry period for the resulting benefits in lactation performance (
Effects of late-gestation heat stress independent of reduced feed intake on colostrum, metabolism at calving, and milk yield in early lactation of dairy cows.
, cooled cows (access to shade, sprinklers, and fans) produced more colostrum (7.1 ± 0.6 kg) with an elevated IgG concentration (92.2 ± 2.5 g/L) compared with heat-stressed cows (access to shade but not to sprinklers or fans; 4.0 ± 0.6 kg; 74.7 ± 2.5 g/L). In addition, compared with the cooled cows, colostrum yield (6.0 ± 0.6 kg) and IgG concentration (88.5 ± 2.5 g/L) did not differ in a third group of cows that were cooled but offered the same amount of feed as the heat-stressed group (
Effects of late-gestation heat stress independent of reduced feed intake on colostrum, metabolism at calving, and milk yield in early lactation of dairy cows.
), reduced feed intake only partially explains a lower colostrum yield as a result of heat stress in the aforementioned study and provides further support for thermal management of dry cows beyond the positive effects on cow and calf productivity (
reported an increase in colostrum yield as the length of the dry period, categorized as < 47, 47–67, or > 67-d, increased. Jersey cows with a 45-d dry period had a 1.7 times greater odds of producing < 2.7 kg of colostrum compared with cows with a 65-d dry period. Further, researchers revealed a 60-d dry period resulted in +2.2 ± 0.4 and +2.6 ± 0.6 kg more colostrum compared with cows managed for a shortened (30–40 d) dry period (
). Additionally, a dry period ≥ 85-d was associated with greater concentrations of colostrum fat, but protein concentration was not affected by dry period length (
Since colostrum synthesis exerts a metabolic demand during late gestation, prepartum diet formulation (discussed above) as well as length of exposure to the close-up ration has been evaluated in 2-phase dry cow systems. Contrary to
Effects of close-up period duration and feeding level on periparturient performance and health of dairy cows. in Department of Veterinary and Animal Sciences. Vol.
Effects of shortening the close-up period length coupled with increased supply of metabolizable protein on performance and metabolic status of multiparous Holstein cows.
observed a trend for a 2.0 ± 0.8 kg greater colostrum yield with a 21-d compared with a 10-d close-up period. The aforementioned increase in yield was larger than that observed in an observational study (10 d = 4.9 ± 0.2 vs. 20 d = 5.2 ± 0.1 kg;
). Yet, when categorized as ≤ 15, 16–30, or > 30 d, time in the close-up pen was not associated with colostrum yield or Brix % in an analysis of 16,032 Holstein cows (
). Further, decreasing stocking density (100% headlock, 109% stalls vs. 80% headlock, 86.3% stalls; Silva et al., 2016 and 120% vs. 100% vs. 80% headlock and stalls; Jiang et al., 2021) of the close-up pen did not affect colostrum yield or Brix percentage. While it appears that total dry period length is more influential for colostrum synthesis compared with time and stocking density of the close-up pen, recent evidence suggests that the interaction of pen move with dry cow booster vaccinations to increase specific calf-health related antibodies in colostrum should also be considered. Cows administered booster vaccinations at 28 d relative to calving and moved to the close-up pen at 21 d relative to calving had greater colostral IgG concentration (160.4 ± 7.0 g/L) compared with cows vaccinated and moved at 21 d relative to calving (134.4 ± 7.0 g/L) but neither treatment differed from cows vaccinated and moved to the close-up pen at 28 d relative to calving (148.3 ± 7.2 g/L) (
). Although replication of these data is lacking, results of this study suggest that vaccination one week earlier and not coinciding with potential detrimental effects of a pen move was more beneficial than earlier vaccination in combination with a pen move. When timing of vaccination is considered independent of pen moves, administration of vaccines earlier in the dry period or given repeatedly, and consistent with manufacturer label recommendations, might offer a management strategy to increase vaccine derived antibodies in colostrum since most colostral immunoglobulins are produced in and transferred from maternal circulation.
Dry off procedure and udder health
Selective and blanket dry cow therapy protocols are commonly used to reduce intramammary infection (
), but limited data are available on their effect on colostrum production. In studies using a teat-sealant only or an antibiotic in addition to a teat sealant on cows with a low risk (SCC < 200,000 cells/mL) for intramammary infection,
found no differences in colostrum fat, protein, lactose, and IgG concentrations as well as the colostrum microbiome. However, the effect of dry-cow therapy might depend on the risk of intramammary infections as the yield of colostrum from a persistently infected gland, defined as growth of ≥ 50 cfu/mL of the respective mastitis-causing pathogen when sampled 14 and 7 d relative to calving, was reduced compared with non-infected glands (
) . Concentrations of most colostral components and bioactive factors (fat, protein, total solids, SCC, immunoglobulins, oligosaccharides, miRNA, insulin, IGF-1, minerals, vitamins, etc.) decrease in subsequent hours to days following parturition while milk yield and lactose concentrations increase (
observed a quadratic relationship between IgG concentration and time from calving to colostrum harvest such that IgG concentration was lower when collected ≥ 8 h post calving. In agreement, other authors have observed decreased colostrum Brix % or IgG concentration in colostrum harvested ≥6 to 9 h post-calving and an increased colostrum yield when harvested ≥12 h post-calving (
Colostrum immunoglobulin G concentration of multiparous Jersey cows at first and second milking is associated with parity, colostrum yield, and time of first milking, and can be estimated with Brix refractometry.
). To maximize colostral components and IgG concentration, we recommend harvesting colostrum ≤ 8 h following calving. Notably, producers that feed a calf its dam's colostrum should prioritize colostrum harvest ≤ 2 h from calving to ensure timely ingestion of colostrum for the newborn calf.
Administration of Oxytocin
As with milk letdown, release of oxytocin from the pituitary gland is a necessary response for a complete colostrum harvest and is most often achieved by tactile teat stimulation (
found that colostrum yield was not affected when the calf was present before and during colostrum harvest or when administering 20 IU of oxytocin intramuscularly 3 min. before manual stimulation in preparation for colostrum harvest, but IgG concentration was increased by 5.3 ± 2.6 and 6.3 ± 2.7 g/L, respectively. Elevated oxytocin concentrations can alter the tight junctions of the mammary gland (
Supraphysiological oxytocin increases the transfer of immunoglobulins and other blood components to milk during lipopolysaccharide-and lipoteichoic acid–induced mastitis in dairy cows.
) which might have affected IgG concentration in the above-mentioned study, leading to the small observed effect. Oxytocin injections have not been associated with changes in fat, protein, or lactose concentrations in milk (
) although the effect of oxytocin administration or presence of the calf on other colostral components has not been reported to the knowledge of the authors. Given findings reported by
originated from a single commercial dairy farm, the external validity on these data remain uncertain, and create a need for additional studies on multiple dairy farms with varying widely used premilking routines. Further, research is needed to determine whether oxytocin administration at colostrum harvest affects the milk letdown reflex at subsequent milkings.
POST-HARVEST COLOSTRUM MANAGEMENT
On-farm Assessment of Colostrum Quality
Assays to determine colostral IgG [radial immunodiffusion (RID), enzyme-linked immunosorbent assay (ELISA), and turbidimetric immune assay (TIA)] are time-consuming and costly, making them infeasible for commercial dairy producers. Moreover, because of a bias between ELISA and TIA when compared with RID (
Comparison of turbidometric immunoassay and brix refractometry to radial immunodiffusion for assessment of colostral immunoglobulin concentration in beef cattle.
J. Vet. Intern. Med.2023; 37 (37596893): 1934-1943
), comparing results between methods is not recommended. However, determining the specific gravity or refractive index of colostrum via a hydrometer and Brix refractometer, respectively, have been investigated for their role as rapid and affordable indirect estimates of colostrum quality. When compared with IgG determined by RID, a hydrometer and Brix refractometer exhibited a moderate to strong correlation (hydrometer: r = 0.58 to 0.79; Brix refractometer: r = 0.64 to 0.75;
Validating a refractometer to evaluate immunoglobulin G concentration in Jersey colostrum and the effect of multiple freeze–thaw cycles on evaluating colostrum quality.
). For the hydrometer, the negative predictive value (probability of a hydrometer result to correctly identify a sample as ≥ 50.0 g of IgG/L) with a cut point of 1,047 was 97.1 (95% CI: 92.8–99.2%;
) suggesting both hydrometers and Brix refractometers offer suitable in-direct estimates to identify high quality colostrum for on-farm use. In a study by
, colostrum collected at the beginning of the milking process resulted in a higher IgG concentration compared with a composite sample and to samples collected during the milking process. Collection of a composite sample from the bucket after the milking process is recommended for quality assessment. Although high-quality colostrum is currently defined as an IgG concentration ≥ 50 g/L, recommended IgG intake through colostrum might change as our understanding of the short-term and long-term benefits of achieving higher concentrations of IgG in the calf rather than merely surpassing a minimum threshold grows (
Along with preserving the nutritional and bioactive components, minimizing contamination is fundamental to successful colostrum management. Feeding contaminated colostrum can reduce absorption of immunoglobulins (
). However, minimizing bacterial contamination and pathogen transfer via colostrum remains an area of opportunity. In an evaluation of 1,241 colostrum samples from 39 Czech farms, only 352 (28.4%) and 1,095 (88.2%) samples were below the industry standard total plate count (<100,000 cfu/mL;
noted that 409 of 746 (54.8%) colostrum samples from 67 farms in the United States were below the industry standard total plate count. As we further understand the effects that bacterial and pathogen contamination have on the calf, industry standard thresholds for total plate and coliform counts among other contaminants might arise or need to be reevaluated. Although some pathogens can shed in the mammary gland, significant pathogen and environmental contamination occur particularly during harvest but also during storage or feeding of colostrum (
). In fact, of the 155 cultured colostrum samples, 21 (13.5%) samples were positive for a gram-positive mastitis agent while 117 (75.5%), 127 (81.9%), and 128 (82.6%) samples resulted in environmental, fecal, and skin and mucosa contaminants, respectively (
). As such, special consideration should be given to identify the risk of pathogen shedding in the mammary gland as well as minimize fecal and environmental contamination (
) as well as rapidly cooling colostrum (using ice or cold water) after harvest and properly treating and storing colostrum can aid in reducing bacterial replication and preserving the nutritional and bioactive components.
Heat Treatment
Heat-treatment can be an effective strategy to decrease total bacterial counts in colostrum with minimal effect on immunoglobulin G concentration when treated at 60°C for 60 min. (
Heat treatment of colostrum on commercial dairy farms decreases colostrum microbial counts while maintaining colostrum immunoglobulin G concentrations.
Heat treatment of colostrum at 60 degrees C decreases colostrum immunoglobulins but increases serum immunoglobulins and serum total protein: A meta-analysis.
). In a recent meta-analysis, the loss of IgG when colostrum was heat treated at ≤ 60°C and 60–63°C was −3.6 (−7.3 to 0.1) and −21.7 (−27.3 to −16.1) g/L, respectively (
A meta-analysis of the effects of colostrum heat treatment on colostral viscosity, immunoglobulin G concentration, and the transfer of passive immunity in newborn dairy calves.
Heat-treated (in single aliquot or batch) colostrum outperforms non-heat-treated colostrum in terms of quality and transfer of immunoglobulin G in neonatal Jersey calves.
, batch heat treatment resulted in a lower total plate count but a higher total coliform count when compared with single bag heat treatment. Notably, neither batch nor bag heat-treatment result in a sterile product and some bacterial species, such as staphylococci and environmental streptococci, appear more tolerant to survive treatment (
Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome.
, heat treating colostrum at 60°C for 60 min. was successful in eliminating inoculated viable infectious agents Mycoplasma bovis (108 cfu/mL), Listeria monocytogenes (106 cfu/mL), Escherichia coli (106 cfu/mL), and Salmonella enteritidis (106 cfu/mL), but Mycobacterium avium subspecies paratuberculosis, the agent causing Johne's disease, inoculated at 103 cfu/mL was recovered in 1 of 4 batches of colostrum. Further, Staphylococcus aureus and coliforms were not detected after heat treating colostrum 60°C for 60 min. (
Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome.
). As such, preventing contamination during colostrum harvest and storage should remain a priority regardless of the use of heat-treatment. Additionally, heat-treatment of colostrum alone was not effective at decreasing the risk of Mychobacterium avium subspecies paratuberculosis transmission (
Effect of feeding heat-treated colostrum on risk for infection with Mycobacterium avium ssp. paratuberculosis, milk production, and longevity in Holstein dairy cows.
). Since colostrum only accounts for one potential source of pathogen exposure, measures should be taken to identify and control other routes of disease transmission concurrently.
Although heat-treatment is an effective strategy to reduce bacterial counts, recent evidence suggests it also alters other colostral components. When inoculating sterile colostrum with fecal E. coli, we observed a greater bacterial growth from 4 to 24 h in heat-treated compared with raw or frozen colostrum (McKane et al., personal communication) suggesting heat treatment decreases the bacteriostatic or bactericidal properties of colostrum. Heat-treatment also increased colostrum viscosity (
A meta-analysis of the effects of colostrum heat treatment on colostral viscosity, immunoglobulin G concentration, and the transfer of passive immunity in newborn dairy calves.
Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome.
Leukocytes, microRNA, and complement activity in raw, heat-treated, and frozen colostrum and their dynamics as colostrum transitions to mature milk in dairy cows.
Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome.
Invited review: Growth-promoting effects of colostrum in calves based on interaction with intestinal cell surface receptors and receptor-like transporters.
Invited Review: Effects of colostrum management on transfer of passive immunity and the potential role of colostral bioactive components on neonatal calf development and metabolism.
Short communication: The effect of heat treatment of bovine colostrum on the concentration of oligosaccharides in colostrum and in the intestine of neonatal male Holstein calves.
). Despite this, feeding colostrum heat-treated at ≤ 60°C to calves resulted in a 2.5 to 6.6 g/L increase in circulating IgG concentration and a 3.8 to 11.5% increase in apparent efficacy of IgG absorption (AEA;
A meta-analysis of the effects of colostrum heat treatment on colostral viscosity, immunoglobulin G concentration, and the transfer of passive immunity in newborn dairy calves.
demonstrated that regardless of heat-treatment, calves fed colostrum with a high bacteria count had a 9.5 to 12.2 g/L lower circulating IgG concentration at 48 h and a 18.7 to 19.9% lower AEA, emphasizing the need to minimize bacterial contamination at time of feeding. In addition to proper sanitation, a combination with heat treatment at 60°C for 60 min or use of an approved colostrum additive (reviewed by
; verify local regulations for approved colostrum additives allowed as a feed additive) should be considered as strategies where needed to secure calf health.
Storage
On-farm storage of colostrum is a critical component of a colostrum management system to preserve colostrum composition and IgG concentration as well as to maintain an adequate supply through seasonal declines in yield. Unless fresh colostrum is fed immediately, it should be rapidly cooled before entering storage in the refrigerator (4°C) or freezer (−20°C). Colostrum stored at room temperature had greater bacteria counts by 6 h and 42 times more bacteria by 48 h compared colostrum stored in the refrigerator (
). However, use of potassium sorbate as a colostrum preservative in combination with refrigeration has been an effective strategy to reduce bacterial growth for 96 h compared with raw colostrum in the refrigerator (
, concentrations of IgG and IgM in bovine colostrum were not affected when storing colostrum in a freezer for 3 mo, but IgG and IgM decreased 14.6 and 60.5%, respectively when stored for 6 mo. Notably, IgG (30.2 ± 3.0 g/L) and IgM (3.0 ± 0.1 g/L) concentrations in the aforementioned study were lower than that typically observed. Freezing human colostrum preserved concentrations of epidermal growth factor, transforming growth factor (TGF)-β2, tumor necrosis factor (TNF)-α, TNF-receptor I, interleukin (IL)-6, IL-10 for 12 mo; however, IgA, IL-8, and TGF- β1 were only stable when frozen for 6 mo (
Validating a refractometer to evaluate immunoglobulin G concentration in Jersey colostrum and the effect of multiple freeze–thaw cycles on evaluating colostrum quality.
). Therefore, colostrum should be frozen in individual meal portions in a manual defrosting freezer. To avoid raising the internal temperature of the freezer, colostrum can be cooled with ice or cold water before entering the freezer and care should be taken to avoid contact between thawed and frozen containers or bags. Colostrum can be thawed/reheated in a water bath at ≤ 60°C (
observed a 20 to 31% loss of IgG. Heating colostrum in the microwave resulted in coagulation likely from uneven heating as well as reduced volume and crude protein (
). As with heat-treatment, exposing colostrum to temperatures > 60°C when thawing can lead to reductions in IgG concentration.
Recently, we have shown freezing colostrum short-term increased abundance of microRNA as well as preserved the activity of the alternative complement pathway and bacteriostatic or bactericidal properties compared with raw colostrum (
Leukocytes, microRNA, and complement activity in raw, heat-treated, and frozen colostrum and their dynamics as colostrum transitions to mature milk in dairy cows.
; McKane et al., personal communication). Similar preservation of bacteriostatic or bactericidal properties have been reported with breast milk after freezing although the activity may decrease with extended storage (
Effects of storage process on the bacterial growth-inhibiting activity of expressed human breast milk on common neonatal pathogens, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae.
Odd-chain and branched-chain fatty acid concentrations in bovine colostrum and transition milk and their stability under heating and freezing treatments.
Leukocytes, microRNA, and complement activity in raw, heat-treated, and frozen colostrum and their dynamics as colostrum transitions to mature milk in dairy cows.
Because calves suckling their dams would naturally experience a gradual decline in nutrient density as well as bioactive concentrations in milk during the first few days of life (
Short communication: The biological value of transition milk: analyses of immunoglobulin G, IGF-I and lactoferrin in primiparous and multiparous dairy cows.
), feeding transition milk (milkings 2–6) to calves after feeding colostrum has been explored. Feeding transition milk for 1 to 3 d in addition to colostrum resulted in an increased preweaning weight gain (
Effect of feeding colostrum at different volumes and subsequent number of transition milk feeds on the serum immunoglobulin G concentration and health status of dairy calves.
). Further, calves fed a 1:1 colostrum:whole milk mixture for 3 d after a colostrum meal had increased intestinal surface area as well as increased villi height compared with calves fed whole milk (
Feeding colostrum or a 1: 1 colostrum: milk mixture for 3 days postnatal increases small intestinal development and minimally influences plasma glucagon-like peptide-2 and serum insulin-like growth factor-1 concentrations in Holstein bull calves.
). Despite its benefit to the calf, feeding transition milk on a commercial dairy farm presents an added management challenge because of the additional equipment and labor required to harvest and feed transition milk to a select group of calves. Research seeking to determine the optimum duration to feed transition milk as well as identifying the short- and long-term benefits to health, growth, development, and future productivity and compare these outcomes when calves are fed maternal transition milk to protocols feeding whole milk and to those using colostrum supplements to replace transition milk will be instrumental in adoption of transition milk programs on commercial dairy farms. Transition milk can be harvested from cows 2 to 6 milkings after calving and can be fed fresh, heat-treated, or stored as described above for colostrum. Further, transition milk can be pooled from multiple cows; however, measures should be taken to lower the risk of disease transmission when pooling transition milk in the same fashion as when pooling colostrum from multiple dams. Alternatively, mixing colostrum supplements with milk has been used as a substitution for harvesting transition milk (
Despite the variables summarized herein, the proportion of variance in colostrum production we have been able to explain remains small, in part, due to the incomplete knowledge of the physiological mechanisms of colostrum formation (Figure 1). Because of the importance of and traditional focus on IgG alone, transfer of IgG into the mammary gland has historically defined colostrogenesis and is believed to begin 3 to 5 weeks before calving when IgG concentrations in the mammary gland exceed the concentration in maternal circulation (
) and numerous hormones (estradiol, progesterone, prolactin, cortisol, leptin, placental lactogen, etc.) have been discussed as having a potential role in colostrum formation as well as the initiation of lactogenesis II (reviewed by
, Bigler et al., 2023). However, the timing and complete cascade of signals that influence these biological mechanisms, as well as active and passive transfer of constituents remain unknown. Understanding these signals as well as the onset of lactogenesis II are particularly important as the capacity, rate, and time of which colostral components enter or are synthesized in the mammary gland could influence the osmotic gradient and as such affect yield as well as the concentration of colostral components.
Figure 1Summary of cow, colostrum harvest, and post-harvest variables identified as focus of future colostrum investigations. Figure was created with BioRender.
The ability to improve colostrum production through prepartum nutrition and management as well as genetic selection remains a plausible and achievable goal. However, because of the high variability observed in colostrum production and limited available data, future research is needed to discover new interventions that directly influence colostrum yield and composition and increase the external validity of existing findings. Further, inclusion of colostrum outcomes and consistent reporting among future transition cow investigations will facilitate subsequent meta-analyses of these typically smaller studies. The mechanisms of how nutritional or management interventions affect colostrum production remains unclear. Attention to the interactions with maternal metabolism and endocrine signals is necessary to understand these regulatory mechanisms.
Lastly, data on the role of harvest and post-harvest management on colostral components as well the effect on health, growth, and future productivity of calves fed colostrum are needed. Research investigating whether harvest procedures for colostrum and transition milk should differ from the procedures used to harvest mature milk are limited at this time. Further, recording colostrum yield and Brix % readings into dairy management software on commercial dairy farms will enable high-powered and externally valid observational data analysis to identify risk factors and genomic trends. Recent evidence suggests heat-treatment, bacterial contamination, refrigeration, and freezing affect colostral components or the absorption of IgG in the calf (
Short communication: The effect of heat treatment of bovine colostrum on the concentration of oligosaccharides in colostrum and in the intestine of neonatal male Holstein calves.
Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome.
Leukocytes, microRNA, and complement activity in raw, heat-treated, and frozen colostrum and their dynamics as colostrum transitions to mature milk in dairy cows.
). Focusing on the nutritional and developmental role of other colostral components and how current post-harvest management affects these components might redirect best-practice guidelines and redefine colostrum quality. Moreover, the use of colostrum as a therapeutic as well as research into the success of treatment protocols using colostrum are needed (
). Lastly, the effect of feeding transition milk as well as practical strategies to harvest and feed transition milk on a commercial farm warrants further investigation.
CONCLUSIONS
Colostrum yield and composition exhibit individual, herd, and seasonal variability. Although multiple animal and environmental variables have been linked with colostrum production, researchers have been mostly unsuccessful in explaining this variability. Prepartum nutrition and management as well as the interaction with maternal metabolism appear to affect colostrum production. However, suitable on-farm strategies to improve colostrum production remain limited, partially because of our incomplete knowledge on the regulatory mechanisms of colostrum formation. Storage of colostrum remains an effective approach to overcome periods of low colostrum supply. Post-harvest colostrum management should limit bacterial contamination and future studies need to quantify the effect on colostral components and ultimately on calf health.
REFERENCES
Abd El-Fattah A.M.
Abd Rabo F.H.R.
El-Dieb S.M.
Satar El-Kashef H.A.
Preservation methods of buffalo and bovine colostrum as a source of bioactive components.
Impact of 2 versus 1 colostrum meals on failure of transfer of passive immunity, pre-weaning morbidity and mortality, and performance of dairy calves in a large dairy herd.
Colostrum production, calf birth weight, and postpartum ovarian follicular activity of dairy cows fed restricted diet with different protein levels during the prepartum period.
Effects of late-gestation heat stress independent of reduced feed intake on colostrum, metabolism at calving, and milk yield in early lactation of dairy cows.
Photoperiod and Temperature-Humidity Index during the Dry-Period Impact Colostrum and Milk Production in Dairy Cattle. in Department of Animal Sciences.
Supplementation of nicotinic acid to prepartum Holstein cows increases colostral immunoglobulin G, excretion of urinary purine derivatives, and feed efficiency in calves.
Comparison of turbidometric immunoassay and brix refractometry to radial immunodiffusion for assessment of colostral immunoglobulin concentration in beef cattle.
J. Vet. Intern. Med.2023; 37 (37596893): 1934-1943
Leukocytes, microRNA, and complement activity in raw, heat-treated, and frozen colostrum and their dynamics as colostrum transitions to mature milk in dairy cows.
Effect of feeding colostrum at different volumes and subsequent number of transition milk feeds on the serum immunoglobulin G concentration and health status of dairy calves.
The concentrations of immunoglobulins in bovine colostrum determined by the gold standard method are genetically correlated with their near-infrared prediction.
Blood mineral and gas concentrations of calves born to cows fed prepartum diets differing in dietary cation-anion difference and calcium concentration.
Heat treatment of colostrum on commercial dairy farms decreases colostrum microbial counts while maintaining colostrum immunoglobulin G concentrations.
Evaluation of factors associated with immunoglobulin G, fat, protein, and lactose concentrations in bovine colostrum and colostrum management practices in grassland-based dairy systems in Northern Ireland.
Combined biotin, folic acid, and vitamin B12 supplementation given during the transition period to dairy cows: Part II. Effects on energy balance and fatty acid composition of colostrum and milk.
Effects of shortening the close-up period length coupled with increased supply of metabolizable protein on performance and metabolic status of multiparous Holstein cows.
Short communication: The effect of heat treatment of bovine colostrum on the concentration of oligosaccharides in colostrum and in the intestine of neonatal male Holstein calves.
Transition diet starch content impacts colostrum and transition milk composition and immunoglobulin G and insulin concentrations in Holstein dairy cattle.
Oligosaccharide concentrations in colostrum, transition milk, and mature milk of primi-and multiparous Holstein cows during the first week of lactation.
Invited Review: Effects of colostrum management on transfer of passive immunity and the potential role of colostral bioactive components on neonatal calf development and metabolism.
Effect of feeding heat-treated colostrum on risk for infection with Mycobacterium avium ssp. paratuberculosis, milk production, and longevity in Holstein dairy cows.
Selenium biofortified alfalfa hay fed in low quantities improves selenium status and glutathione peroxidase activity in transition dairy cows and their calves.
Effect of supplementing calcium salts of n-3 and n-6 fatty acid to pregnant nonlactating cows on colostrum composition, milk yield, and reproductive performance of dairy cows.
Extended colostrum feeding for 2 weeks improves growth performance and reduces the susceptibility to diarrhea and pneumonia in neonatal Holstein dairy calves.
Effect of organic zinc, manganese, copper, and selenium chelates on colostrum production and reproductive and lameness indices in adequately supplemented Holstein cows.
Factors influencing the immunoglobulin concentration in the first colostrum in Holstein-Friesian dairy cows and their relationship to the postpartum calcium concentration in blood and colostrum.
Tierarztl. Prax. Ausg. G Grosstiere Nutztiere.2017; 45 (29099901): 331-341
Effects of feeding synthetic zeolite A during the prepartum period on serum mineral concentration, oxidant status, and performance of multiparous Holstein cows.
Pattern of milk yield and immunoglobulin concentration and factors associated with colostrum quality at the quarter level in dairy cows after parturition.
Heat-treated (in single aliquot or batch) colostrum outperforms non-heat-treated colostrum in terms of quality and transfer of immunoglobulin G in neonatal Jersey calves.
Effects of storage process on the bacterial growth-inhibiting activity of expressed human breast milk on common neonatal pathogens, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae.
Heat treatment of colostrum at 60 degrees C decreases colostrum immunoglobulins but increases serum immunoglobulins and serum total protein: A meta-analysis.
Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome.
Effect of dry period dietary energy level in dairy cattle on volume, concentrations of immunoglobulin G, insulin, and fatty acid composition of colostrum.
Validating a refractometer to evaluate immunoglobulin G concentration in Jersey colostrum and the effect of multiple freeze–thaw cycles on evaluating colostrum quality.
Effects of replacing inorganic salts of trace minerals with organic trace minerals in the diet of prepartum cows on quality of colostrum and immunity of newborn calves.
Invited review: Growth-promoting effects of colostrum in calves based on interaction with intestinal cell surface receptors and receptor-like transporters.
The impact of direct-fed microbials and enzymes on the health and performance of dairy cows with emphasis on colostrum quality and serum immunoglobulin concentrations in calves.
J. Anim. Physiol. Anim. Nutr. (Berl.).2018; 102 (29030887): e641-e652
Plasma bovine placental lactogen concentration throughout pregnancy in the cow; relationship to stage of pregnancy, fetal mass, number and postpartum milk yield.
Feeding colostrum or a 1: 1 colostrum: milk mixture for 3 days postnatal increases small intestinal development and minimally influences plasma glucagon-like peptide-2 and serum insulin-like growth factor-1 concentrations in Holstein bull calves.
A meta-analysis of the effects of colostrum heat treatment on colostral viscosity, immunoglobulin G concentration, and the transfer of passive immunity in newborn dairy calves.
Impact of a ration negative in dietary cation–anion difference and varying calcium supply fed before calving on colostrum quality of the dams and health status and growth performance of the calves.
Preweaned heifer management on US dairy operations: Part II. Factors associated with colostrum quality and passive transfer status of dairy heifer calves.
Effects of feeding 25-hydroxyvitamin D3 with an acidogenic diet during the prepartum period in dairy cows: Mineral metabolism, energy balance, and lactation performance of Holstein dairy cows.
Colostrum immunoglobulin G concentration of multiparous Jersey cows at first and second milking is associated with parity, colostrum yield, and time of first milking, and can be estimated with Brix refractometry.
Effects of close-up period duration and feeding level on periparturient performance and health of dairy cows. in Department of Veterinary and Animal Sciences. Vol.
The Blood Immune Cell Count, Immunoglobulin, Inflammatory Factor, and Milk Trace Element in Transition Cows and Calves Were Altered by Increasing the Dietary n-3 or n-6 Polyunsaturated Fatty Acid Levels.
Effect of Various Levels of Dietary Protein in Transition Period on Colostrum Quality and Serum Immunoglobulin Concentration in Holstein Cows and their Newborn Calves.
Short communication: The biological value of transition milk: analyses of immunoglobulin G, IGF-I and lactoferrin in primiparous and multiparous dairy cows.
The effect of maternal supply of rumen-protected protein to Holstein Friesian cows during the dry period on the transfer of passive immunity and colostral microbial composition.
Supraphysiological oxytocin increases the transfer of immunoglobulins and other blood components to milk during lipopolysaccharide-and lipoteichoic acid–induced mastitis in dairy cows.
Odd-chain and branched-chain fatty acid concentrations in bovine colostrum and transition milk and their stability under heating and freezing treatments.
00034-1&id=gr1.jpg){kind=link}