Apparent Efficiency Of IgG Absorption Research Articles

Effects of prenatal dietary rumen-protected choline supplementation during late gestation on calf growth, metabolism, and vaccine response.

The objective of this study was to examine the effects of prenatal supplementation and dose of rumen-protected choline (RPC) on neonatal calf growth, metabolism, and vaccine response. Parous Holstein cows were blocked by calving month and randomly assigned within block to receive 45 g/d of RPC [20.4 g/d of choline ions (CHOL45), n = 19], 30 g/d of RPC [13.6 g/d of choline ions (CHOL30), n = 22], or no RPC (CON, n = 19) as a top-dress, starting 24 d before expected calving. Calf body weights were recorded for the first 3 wk of life. All calves were fed colostrum replacer (300 g of IgG) at birth, and apparent efficiency of IgG absorption was calculated. On d 1, 7, 14, and 21, blood samples were taken to quantify plasma reactive oxygen and nitrogen species, antioxidant potential, haptoglobin, nonesterified fatty acids (NEFA), β-hydroxybutyrate, and glucose. Calves received an intranasal vaccine at birth, and nasal secretions were collected on d 0, 7, 10, 14, and 21 to quantify bovine respiratory syncytial virus-specific IgA. Data were analyzed using linear mixed models including the fixed effects of treatment, time (when applicable), calf sex, and prepartum dam data (-24 d) along with interactions. Treatment did not affect calf body weight, β-hydroxybutyrate, or glucose concentrations. For apparent efficiency of IgG absorption, treatment interacted with the dam's prepartum body condition score. Where the dam's body condition score was ≤3.25, IgG absorption was reduced in calves born from CHOL45 dams as compared with calves from either CHOL30 or CON dams. Calves from CHOL30 dams had a lesser oxidative stress index (OSi; reactive oxygen and nitrogen species/antioxidant potential) than calves from CON dams. Haptoglobin concentrations were less in heifer calves from CHOL45 dams as compared with heifers from CON dams. The dam's prepartum NEFA concentration interacted with treatment. When dam NEFA was minimal, calves from CHOL45 and CHOL30 dams had greater or tended to have greater NEFA, respectively. Conversely, when dam NEFA was greater, calves from CHOL30 and CHOL45 dams had lesser or tended to have lesser NEFA than calves from CON dams, respectively. For vaccine response, treatment interacted with the dam's prepartum OSi. Among calves born from dams with a greater OSi, calves from CHOL45 and CHOL30 dams had lesser bovine respiratory syncytial virus-specific IgA concentrations in nasal secretions as compared with CON. Prenatal RPC supplementation during late gestation affected IgG absorption, neonatal calf metabolism, and vaccine response with some effects dependent on the dam's prepartum parameters.

Effect of formic acid treatment on colostrum quality, and on absorption and function of immunoglobulins: a randomized controlled trial in Holstein dairy calves

BackgroundGood quality colostrum is characterized by high immunoglobulin concentration and low pathogen load. Some methods of pathogen reduction can decrease immunoglobulin concentration and potentially affect their function. Objectives were to determine the effect of formic acid treatment on colostral bacterial and immunoglobulin (IgG) levels before feeding, and serum immunoglobulin concentration and neutralizing capabilities after feeding. Fifteen female Holstein calf pairs born < 12 h apart from different dams were randomly assigned to receive four liters of either untreated pooled (both dams) colostrum (MC) or colostrum acidified to pH 4.0–4.5 (AC). Colostrum characteristics estimated; pH, bacterial load, IgG concentration, and neutralization of Infectious Bovine Rhinotracheitis (IBRV/BoHV-1), Bovine Viral Diarrhea (BVDV) Types 1 and 2. Blood samples were collected on days 1, 3 and monthly for 6 months and were analyzed for IgG, and both viral plus leptospiral neutralization, and total protein (day 3 only).ResultsCompared to MC (mean 6.7, SD 0.4; median 6.8, range 6.0–7.3), AC pH was significantly reduced (mean 4.3, SD 0.2; median 4.3, range 4.0–4.5; P < 0.001). Total coliform count (cfu/mL) was also reduced (MC mean 149, SD 444; median 1, range 0–1,700; AC mean 8, SD 31; median 0, range 0–120; P = 0.02). Colostrum IgG concentration was not significantly different between MC (mean 93.3, SD 39.7; median 92.8, range 36.7–164.4 g/L) and AC (mean 101.9, SD 36.7; median 108.3, range 33.8–164.4 g/L; P = 0.54). In calves, serum IgG peaked on day 3 (MC mean 26.1, SD 34.9; median 169.2, range 8.3–151.0 g/L; AC mean 30.2, SD 48.7; median 188.8, range 3.1–204.4 g/L; P = 0.77), and apparent efficiency of IgG absorption was not different between groups (MC mean 24.3, SD 11.4, median 25.3, range 8.6–51.3%; AC mean 22.6, SD 21.7, median 21.6, range 4.1–58.9%; P = 0.65). Thereafter, IgG levels declined but did not differ between groups. MC and AC serum neutralizing titers for IBRV, BVDV Types 1 and 2, or Leptospira interrogans serovars Canicola, and Pomona and L. borgpetersenii serovar Hardjo were not different.ConclusionsColostrum acidification significantly decreased bacterial load fed to newborn calves without affecting colostral IgG concentration or virus neutralization. In addition, acid treatment did not affect serum IgG concentration in calves or its activity against common pathogens.

Effects of maternal level of dietary cation-anion difference fed to prepartum nulliparous cows on offspring acid-base balance, metabolism, and growth

The objectives were to determine the effects of dietary cation-anion difference (DCAD) fed to pregnant cows during the last 22 d of gestation on offspring acid-base balance, metabolism, growth, and health preweaning. A total of 132 nulliparous Holstein cows were enrolled at 250 (248 to 253) d of gestation in a randomized block design. Cows were blocked by genomic merit of energy-corrected milk yield and assigned randomly to diets varying in DCAD: +200 (P200, n = 43), -50 (N50, n = 45), or -150 (N150, n = 44) mEq/kg of dry matter (DM). Newborn calves (15 males and 28 females in P200, 22 males and 23 females in N50, and 18 males and 26 females in N150) were followed for the first 7 or 56 d of age if males or females, respectively. Measures of acid-base balance and concentrations of minerals in blood were measured in all calves on d 0 before colostrum feeding, and on d 1, 3, and 7. Each calf was fed 3.78 L of colostrum from the respective treatment, and apparent efficiency of IgG absorption was determined. All calves were weighed at birth, and females were weighed again at 21, 42, and 56 d of age. Concentrations in serum of total calcium (tCa), total magnesium (tMg), and total phosphorus (tP) were measured up to 56 d of age; intakes of milk and starter grain DM were measured daily from 21 to 56 d of age; and incidence of disease was recorded for the first 56 d of age in females. Treatment did not affect acid-base balance measured in all calves. Calves were born with metabolic and respiratory acidosis, which reversed by 1 d of age. In the first 24 h after birth, blood pH increased from 7.215 to 7.421 and bicarbonate from 26.2 to 31.7 mM, whereas partial pressure of CO2 decreased from 64.1 to 48.7 mm of Hg in all treatments. Maternal DCAD did not affect colostrum IgG content fed to calves (P200 = 95.0 vs. N50 = 91.0 vs. N150 = 97.1 ± 4.1 g/L) or apparent efficiency of IgG absorption (P200 = 33.1 vs. N50 = 33.1 vs. N150 = 34.2 ± 1.9%). Males were born heavier than females, but maternal DCAD did not affect birth weight of all calves (P200 = 37.7 vs. N50 = 37.3 vs. N150 = 37.8 ± 0.7 kg) or daily weight gain in females in the first 56 d of life (P200 = 0.80 vs. N50 = 0.81 vs. N150 = 0.77 ± 0.03 kg/d). Treatment did not affect intake of milk (P200 = 1.11 vs. N50 = 1.04 vs. N150 = 1.19 ± 0.06 kg/d) or starter grain DM (P200 = 0.27 vs. N50 = 0.27 vs. N150 = 0.21 ± 0.06 kg/d), or measures of feed efficiency. Treatment did not affect concentrations of minerals in serum, morbidity, or age at morbidity. Manipulating the DCAD of pregnant nulliparous dams during late gestation did not affect offspring performance in the first 2 mo of age.

Effect of β-carotene supplementation to prepartum Holstein cows on colostrum quality and calf performance

β-Carotene, a pro-vitamin A carotenoid, acts as an antioxidant, able to scavenge free radicals to prevent oxidative damage. It has also been shown to increase rumen microbial production in vitro. When supplemented prepartum, β-carotene increased colostral fat and protein concentrations. The objective of this experiment was to evaluate the effects of supplementing 700 mg/d β-carotene (BC) daily for 4 wk prepartum on cow performance, colostrum, and performance in subsequent calves. Eighteen multiparous Holstein cows housed in a tiestall barn were blocked by expected calving date and randomly assigned to treatments at 4 wk prepartum. Blood samples were collected 3 times a week for analysis of nonesterified fatty acids, ketones, β-carotene, and IgG. Urine samples were also collected 3 times a week for analysis of creatinine and purine derivatives. Colostrum was collected within 90 min after parturition. Calves were removed from their dams before suckling, weighed within 30 min of birth, and received 4 L of maternal colostrum. Blood samples were collected from calves before colostrum administration (0 h) and at 24 h via jugular venipuncture for analysis of IgG concentration and apparent efficiency of IgG absorption. The 18 calves born were blocked based on treatments of dams. All calves were fed 449 g/d dry matter of milk replacer (20% crude protein, 20% fat) and an 18% crude protein textured starter and water ad libitum at 2 d of age until weaning at 42 d. There were no differences in any blood parameters of cows during the prepartum period. Supplemental BC increased the solids content of colostrum compared with control (22.89% control; 27.75% BC). Calves born from control fed cows had greater efficiency of IgG absorption than those born from BC supplemented cows (52.16% control; 39.50%, BC). Calves born from BC fed cows had greater feed efficiency (average daily gain/dry matter intake) compared with those born from control supplemented cows (0.33 for control; 0.44 for BC). These data indicate that although supplementing β-carotene to cows in the prepartum period negatively affects apparent efficiency of IgG absorption, it improved feed efficiency in calves.

The effect of various heat-treatment methods on colostrum quality, health and performance of dairy calves

To investigate the effect of feeding heat-treated colostrum at different duration on the health and performance, 48 Holstein calves were enrolled randomly into four treatment groups before first feeding and consumed untreated colostrum (H0, n = 12), heat-treated colostrum at 60ºC for 30 min. (H30, n = 12), heat-treated colostrum at 60ºC for 60 min. (H60, n = 12) and heat-treated colostrum at 60ºC for 90 min. (H90, n = 12). Blood samples were collected for analyses of IgG and protein profile at 0, 6, and 24h of age. The colostrum sample from treated and untreated batches and feces sample from each calf also were taken. The results showed heat-treatment of colostrum at 60ºC for 60 (p = 0.03) and 90 min. (p = 0.01) reduced total bacterial count, while colostral IgG concentration maintained up to 60 min. Serum total protein (p = 0.02), IgG concentrations (p = 0.03), and apparent efficiency of IgG absorption (p = 0.02) were significantly greater at 6 and 24h in calves that were fed heat-treated colostrum (H90) compared to calves fed unheated colostrum (H0). General health status of calves that were received heat-treated colostrum was better and the prevalence of diarrhea-induced pathogens was lower than calves were fed unheated colostrum. In conclusion, the consumption of heat-treated colostrum had a positive effect on health, growth characteristics, and performance of calves during the suckling period.

The effect of various heat-treatment methods on colostrum quality, health and performance of dairy calves

ABSTRACT. To investigate the effect of feeding heat-treated colostrum at different duration on the health and performance, 48 Holstein calves were enrolled randomly into four treatment groups before first feeding and consumed untreated colostrum (H0, n = 12), heat-treated colostrum at 60oC for 30 min. (H30, n = 12), heat-treated colostrum at 60oC for 60 min. (H60, n = 12) and heat-treated colostrum at 60oC for 90 min. (H90, n = 12). Blood samples were collected for analyses of IgG and protein profile at 0, 6, and 24h of age. The colostrum sample from treated and untreated batches and feces sample from each calf also were taken. The results showed heat-treatment of colostrum at 60oC for 60 (p = 0.03) and 90 min. (p = 0.01) reduced total bacterial count, while colostral IgG concentration maintained up to 60 min. Serum total protein (p = 0.02), IgG concentrations (p = 0.03), and apparent efficiency of IgG absorption (p = 0.02) were significantly greater at 6 and 24h in calves that were fed heat-treated colostrum (H90) compared to calves fed unheated colostrum (H0). General health status of calves that were received heat-treated colostrum was better and the prevalence of diarrhea-induced pathogens was lower than calves were fed unheated colostrum. In conclusion, the consumption of heat-treated colostrum had a positive effect on health, growth characteristics, and performance of calves during the suckling period.

Long-term impacts of late-gestation maternal heat stress on growth performance, blood hormones and metabolites of newborn calves independent of maternal reduced feed intake

The objective of this study was to evaluate the effects of heat stress in late gestation independent of maternal reduced feed intake on performance, blood hormones and metabolites, and immune responses of dairy calves from birth through weaning. A total of 30 multiparous Holstein cows at 45 d before expected calving were randomly assigned to one of 3 groups: (1) thermal neutral (CL, n = 10) conditions with ad libitum feed intake (10% of refusals on an as-fed basis); (2) pair-fed thermal neutral (CLPF, n = 10) conditions to reduce feed intake to levels similar to the heat stress (HS) group while reared under thermoneutral conditions (80% of the CL group); or (3) heat stress (HS, n = 10) conditions with ad libitum feed intake. Pair-feeding was conducted to quantify the confounding effects of dissimilar feed intake. Calves (10/group) born to cows that were exposed to cooling (IU-CL), pair-feeding (IU-CLPF), or heat stress (IU-HS) were used from birth through weaning. After birth, all the calves were managed under identical conditions. IU-HS calves had lower birth weight, and hip height at birth and 14 d of age. Compared with IU-CL and IU-CLPF calves, IU-HS calves had lower serum concentration of IgG and apparent efficiency of IgG absorption but higher serum insulin concentrations. Cortisol concentration in serum was higher in IU-HS and IU-CLPF calves compared to IU-CL calves. The neutrophil percentage was lower in IU-CL calves than in IU-HS and IU-CLPF calves. Neutrophil-lymphocyte ratio was higher in IU-HS calves compared to IU-CLPF and IU-CL calves. The mRNA expression of TNFα of IU-HS calves was downregulated compared with IU-CL and IU-CLPF calves. In summary, maternal HS during late gestation reduces calf birth weight and dramatically alters blood hormones and metabolites, but its effect on immune system function was not independent of maternal reduced feed intake.

Effect of supplementation fat during the last 3 weeks of uterine life and the preweaning period on performance, ruminal fermentation, blood metabolites, passive immunity and health of the newborn calf.

The objective of this study was to evaluate the effects of supplementing essential fatty acids (FA), during late gestation and the preweaning and early weaning periods on passive immunity, growth, health, rumen fermentation parameters, blood metabolites and behaviour of dairy calves. During the last 3 weeks of pregnancy, cattle (n 120), within parity, were randomly assigned to one of three diets with different fat supplements: (a) no supplemental fat (CON), (b) supplement rich in linoleic acid (CSO), or (c) supplement rich in EPA and DHA (CFO). Eighty-four newborn Holstein calves were randomly assigned, within the prepartum diets, to one of two calf starters: no fat supplement (FC-0) or 2 % Ca-salt of unsaturated FA (FC-2). Overall, the interaction between dam diets and calf starters did not affect calf performance or any other parameter measured. Calves born from dams fed fat (CSO or CFO) performed better than calves born from dams fed CON. Namely, calves born from dams fed fat had greater plasma concentrations of IgG (P < 0·01), better apparent efficiency of IgG absorption (P < 0·01) and average daily gain (ADG, 597 v. 558 g/d; P = 0·02), and lower rectal temperature (RT; P < 0·01). Calves fed a calf starter rich in unsaturated FA (FC-2) had greater (P ≤ 0·01) ADG, skeletal growth, feed efficiency, and weaning weight compared with FC-0-fed calves. Furthermore, calves fed FC-2 had lower RT during the pre- and post-weaning periods (P ≤ 0·04) and fewer days with diarrhoea (P < 0·001) compared with calves fed CF-0. Time spent eating, ruminating, standing, lying, and on non-nutritive oral behaviour did not differ by treatment. Similarly, treatments did not affect ruminal fermentation parameters. At 28 and 77 d of age, calves fed CF-2 had higher plasma concentrations of albumin and cholesterol (P ≤ 0·02) and lower urea N compared with calves fed CF-0. Plasma concentrations of alkaline phosphatase were higher in calves fed CF-2 compared with those fed CF-0, when they were 77 d old. These findings support feeding moderate amounts of long-chain PUFA during late uterine life or during the preweaning period have beneficial effects on calf metabolism, growth, and health performance.

Effect of different heating times of high-, medium-, and low-quality colostrum on immunoglobulin G absorption in dairy calves

The objective of this study was to determine the effect of different durations of heat treatment on passive transfer of IgG from high-, medium- and low-quality colostrum. Colostrum was collected from The Pennsylvania State University dairy herd and divided by quality (high, medium, or low) based on colostrometer measurements. Colostrum was pooled by quality to create 3 unique batches. Each batch was further divided in thirds as follows: frozen to be fed without heat treatment, heated at 60°C for 30 min, or heated at 60°C for 60 min. Colostrum samples from each treatment were collected and analyzed for standard plate count, gram-negative noncoliforms, coliforms, and total IgG concentration. Serum samples were collected from 108 Holstein calves before feeding colostrum and 24 h after birth. Blood samples were analyzed for total protein, total IgG, and hematocrit. Colostrum quality (high, medium, or low), heat treatment (unheated, 60°C for 30 min or, 60°C for 60 min), and their interaction were analyzed as fixed effects, with calf sex included as a random block effect. Colostrum IgG was different between quality groups (92.5, 59.4, and 48.1 mg/mL of IgG). Heating colostrum reduced IgG concentration compared with the control by 9% when heated for 30 min and by 12% when heated for 60 min. Colostrum heated for 60 min had a lower standard plate count than colostrum heated for 30 min or not heated (1.8, 2.0, and 3.6 log cfu/mL, respectively). Serum IgG concentration at 24 h increased as colostrum quality increased (18.0, 22.2, and 24.8 mg/mL) and tended to increase as heat treatment time increased (19.7, 20.3, and 25.0 mg/mL of IgG). Apparent efficiency of IgG absorption was greater in calves that received medium-quality colostrum compared with calves fed high-quality colostrum (38.1 and 25.0%, respectively). These results suggest an upper limit may exist to the amount of IgG absorption in a given time period and that medium- or high-quality colostrum yields similar blood IgG concentration given the same volume of intake.

Comparison of immune responses in calves fed heat-treated or unheated colostrum

Understanding the mechanisms that underlie neonatal immune function is important for appropriately treating and preventing disease. Cytokines provided in colostrum may affect immune development and function, but data describing cytokine absorption in calves and the effects of colostrum heat treatment on absorption are limited. The objectives of this experiment were to characterize immune responses in calves that received heat-treated (HT) or unheated (UH) colostrum (in terms of growth, rectal temperature, and blood cytokine and IgG concentrations) and to determine calves' ability to absorb IFNγ and IL1β from HT and UH colostrum. A single large batch of colostrum was divided to create treatments. The HT colostrum was heated to 60°C for 60 min. Both treatments were frozen until needed and warmed immediately before feeding. Bull calves (n = 26) were randomly assigned to receive 8% of their birth weight in colostrum from 1 treatment at birth. Blood was collected at 0 and 24 to 48 h after birth for IL1β, IFNγ, and IgG analyses. Subcutaneous injections of ovalbumin (5.0 mg/mL) were given at 14 and 35 ± 3 d of age. Rectal temperature and growth were monitored for 10 d following each injection. Plasma samples were collected at 0, 4, 8, and 12 h post-injection and daily for the subsequent 10 d to measure IL1β, IFNγ, and IgG concentrations. Colostrum heat treatment failed to increase blood IgG concentrations or the apparent efficiency of IgG absorption. Serum IL1β concentrations were higher in UH calves 24 to 48 h after birth and remained higher than those in HT calves through 15 d of age. Both IFNγ and IgG increased in response to ovalbumin injection; we observed no differences between treatments. Rectal temperature increased and peaked 12 h after injection at 14 and 35 d. Growth rate was reduced by exposure to the foreign antigen. Interactions of calf age and colostrum treatment with time post-injection indicate that calves tended to show greater loss in average daily gain at 35 d than at 14 d, and UH calves tended to recover greater rates of growth 6 to 10 d after receiving ovalbumin injection. Thus, feeding HT colostrum did not inhibit neonatal immune response, but it may have affected recovery from exogenous antigen challenge.

Effect of difructose anhydride III supplementation on passive immunoglobulin G transfer and serum immunoglobulin G concentration in newborn Holstein calves fed pooled colostrum

Difructose anhydride (DFA) III acts on intestinal epithelial tight junctions and promotes calcium absorption through the paracellular pathway in dairy cows. This trial was done to investigate the effects of DFA III supplementation on passive IgG transfer and serum IgG concentration in calves. Twenty-four newborn Holstein male calves were grouped as 12 pairs, with each pair receiving a separate batch of pooled colostrum (PC) from the first 2 milkings. One calf from each pair was allocated to the treatment group (n=12) and received 18g of DFA III in each feeding; the other calf was assigned to the control group (n=12) and did not receive DFA III. All calves were fed 2 L of PC per feeding at 1, 10, and 24 h after birth. Prefeeding blood samples taken at 0 h, 10 h, 24 h, 36 h, 4 d, and 7 d were analyzed for serum IgG concentration. Apparent efficiency of IgG absorption in the treatment group was higher compared to that in the control group. Serum IgG concentration of calves in the treatment group was higher for all sampling time points except for 0 h of age. Mean serum IgG concentrations in the treatment and control groups at 36 h of age were 22.3 and 17.7 g/L, respectively. Serum IgG concentration at 36 h of age was positively related with the IgG concentration in the PC in both groups, and it was higher in the treatment group than in the control group at the same IgG concentration in the PC. These results indicate that absorption of ingested IgG by endocytosis as well as a nonselected concentration gradient process of the paracellular pathway of the intestinal epithelium could be enhanced by DFA III supplementation. Supplementation of DFA III in PC containing various IgG concentrations could improve IgG absorption as well as calf serum IgG concentration.

Effect of colostrum heat treatment and bacterial population on immunoglobulin G absorption and health of neonatal calves

Improved IgG absorption in calves fed heat-treated colostrum has been attributed to the reduced bacteria content in colostrum after heat treatment. However, at least one study reported that colostrum bacteria content did not affect IgG absorption. The main objective of the current study was a more conclusive test of the combined effects of colostrum bacteria content and heat treatment on IgG absorption. Comparison of conclusions from plasma IgG as measured by radial immunodiffusion and ELISA and comparison of health scores in the first week of life were secondary and tertiary objectives. Colostrum from individual cows was pooled, divided, either heat treated or unheated, and allowed to incubate for bacterial growth or not. The 4 treatments were unheated, low bacteria; unheated, high bacteria; heat-treated, low bacteria; and heat-treated, high bacteria. Plasma samples were collected from bull calves (n=25–27 per treatment) before and 48h after colostrum feeding for IgG and total protein analysis. Fecal, respiratory, and general health scores were assigned daily for the first 7 d. Plasma IgG, total protein, apparent efficiency of IgG absorption, and frequency of illness were analyzed using the MIXED and FREQ procedures in SAS (SAS Institute Inc., Cary, NC). Plasma IgG values from ELISA were lower than radial immunodiffusion; however, conclusions were similar. Greater colostrum bacteria content reduced total protein, plasma IgG, and efficiency of IgG absorption. Heat treatment tended to improve 48-h plasma IgG as measured by ELISA. Respiratory scores were not affected by colostrum treatment, but calves fed heat-treated, low-bacteria colostrum tended to experience fewer scour days. These results provide conclusive evidence for the benefits of minimizing bacterial contamination in colostrum for feeding calves.

Effect of heat stress during late gestation on immune function and growth performance of calves: Isolation of altered colostral and calf factors

Calves born to cows exposed to heat stress during the dry period and fed their dams’ colostrum have compromised passive and cell-mediated immunity compared with calves born to cows cooled during heat stress. However, it is unknown if this compromised immune response is caused by calf or colostrum intrinsic factors. Two studies were designed to elucidate the effects of colostrum from those innate to the calf. The objective of the first study was to evaluate the effect of maternal heat stress during the dry period on calf-specific factors related to immune response and growth performance. Cows were dried off 46 d before expected calving and randomly assigned to 1 of 2 treatments: heat stress (HT; n=18) or cooling (CL; n=18). Cows of the CL group were housed with sprinklers, fans and shade, whereas cows of HT group had only shade. After calving, the cows were milked and their colostrum was frozen for the subsequent study. Colostrum from cows exposed to a thermoneutral environment during the dry period was pooled and stored frozen (−20°C). Within 4h of birth, 3.8L of the pooled colostrum from thermoneutral cows was fed to calves born to both HT and CL cows. Day of birth was considered study d 0. All calves were exposed to the same management and weaned at d 49. Blood samples were collected before colostrum feeding, 24h after birth and twice weekly up to d 28. Total serum IgG concentrations were determined. Body weight was recorded at birth and at d 15, 30, 45, and 60. Relative to CL calves, HT calves were lighter at birth (38.3 vs. 43.1kg), but no difference in weight gain was observed at d 60. Additionally, HT calves had lower apparent efficiency of IgG absorption (26.0 vs. 30.2%), but no differences were observed for total IgG concentration. The objective of the second study was to evaluate the isolated effect of the colostrum from HT cows on calf immune response and growth performance. The experimental design was identical to the first study, but all calves were born to cows under thermoneutral conditions during the dry period. At birth, calves were blocked by sex and birth weight and then randomly assigned to 1 of 2 treatments, which meant they received pooled colostrum from HT cows or CL cows. No treatment effect was observed on passive immune transfer or on postnatal growth. Thus, heat stress during the last 6 wk of gestation negatively affects the ability of the calf to acquire passive immunity, regardless of colostrum source.

Effect of the mass of immunoglobulin (Ig)G intake and age at first colostrum feeding on serum IgG concentration in Holstein calves

Forty-four Holstein calves (19 male and 25 female) were used in this study of the relationships among age at first colostrum feeding, IgG intake, and apparent efficiency of IgG absorption. Time of birth was recorded for each calf and the calves were fed colostrum ad libitum after birth at either 0930 or 1630h. Blood samples were collected immediately before and 24h after colostrum feeding. Data from calves were then categorized into 4 groups representing time from birth to colostrum feeding: A=fed within 1h (n=5); B=fed from 1 to 6h (n=10); C=fed from 6 to 12h (n=21); and D=fed from 12 to 18h (n=8) after birth. Average total intake of colostrum was 3.6±0.1L. Over 80% of the calves consumed ≥3L of colostrum. Apparent efficiency of IgG absorption declined remarkably 12h after birth. Mean apparent efficiency of absorption of IgG in group D (15.8±3.0%) was lower than that in groups A (30.5±3.9%) and B (27.4±2.8%). Serum IgG concentration in calves was positively correlated with IgG intake in all groups. The relationship between mass of IgG consumed and calf serum IgG at 24h was different for each time of colostrum feeding, with only limited differences observed between groups A and B. We concluded that failure of transfer of passive immunity in newborn calves may be avoided if calves consume ≥3L of colostrum with IgG concentration >40mg/mL within 6h after birth. These findings help define the opportunity to minimize failure of transfer of passive immunity to newborn calves under management programs similar to those used on commercial dairy farms.

Efficacy of feeding a lacteal-derived colostrum replacer or pooled maternal colostrum with a low IgG concentration for prevention of failure of passive transfer in dairy calves

To compare the efficacy of a lacteal-derived colostrum replacer (LDCR) for the prevention of failure of passive transfer of immunity (FPT) in calves with that of pooled maternal colostrum (MC). Randomized field trial. 568 heifer calves from 1 California dairy. Calves were randomly allocated to 1 of 2 treatment groups and fed 2 doses (200 g of IgG) of an LDCR or 3.8 L of pooled MC. From each calf, blood samples were collected before and approximately 24 hours after treatment. Serum IgG and total protein (TP) concentrations were quantified with standard methods, and the apparent efficiency of IgG absorption was calculated. At 24 hours after treatment, mean serum TP and IgG concentrations were significantly lower for calves fed pooled MC (TP, 4.77 g/dL; IgG, 7.50 g/L), compared with those for calves fed the LDCR (TP, 5.50 g/dL; IgG, 15.15 g/L). Calves fed the LDCR were 95% less likely to develop FPT (OR, 0.05; 95% confidence interval, 0.03 to 0.08) than were calves fed pooled MC. However, the mean IgG concentration in the pooled MC fed during the study (21.1 g/L) was substantially lower than that (64.3 g/L) determined for representative samples of pooled MC from other southwestern US dairies during a national survey. Results indicated that, on this particular dairy, calves fed an LDCR were at less risk of developing FPT than were calves fed pooled MC. The LDCR evaluated was a viable alternative for the prevention of FPT in calves.

Evaluation of immunoglobulin G absorption from colostrum supplements gavaged to newborn piglets

Absorption of energy and IgG at birth from colostrum may improve survival and immune competency of newborn piglets. Adequate intake of colostrum may be difficult for piglets due to low birth weight, birth order, or viability. This study was designed to evaluate orally fed colostrum supplements with different energy sources and IgG from porcine plasma on piglet serum IgG content and absorption of IgG compared to pooled sow colostrum. Ninety-six newborn piglets from 12 sows with an average birth weight of 1,288 g were used. Eight piglets were removed from each sow immediately at birth, prior to suckling, and randomly allotted to receive either pooled sow colostrum or 1 of 3 colostrum supplements (A, B, and C) fed at 2 dosing schemes. Piglets received their allotted treatment as either one 30-mL dose at 0 h or three 10-mL doses at 0, 2, and 4 h. Piglets received ad libitum access to water at 2-h intervals after receiving their last treatment dose. Twelve hours after the first dose, piglets were weighed and 4 mL of blood was collected. Plasma IgG content, apparent efficiency of absorption, hematocrit, protein, and glucose were determined. Birth weight and final BW did not differ between treatments; however, pigs fed sow colostrum lost more weight (-72 g) than pigs fed colostrum supplements (-40 g; P < 0.001). Differences in hematocrit or serum glucose were not detected. Serum protein was higher (P < 0.05) in piglets fed colostrum supplements than in pigs fed sow colostrum. Serum IgG content did not differ among treatments. Apparent efficiency of IgG absorption was greatest for sow colostrum followed by colostrum supplements B, A, and C (28.5, 27.6, 25.5, and 24.7%, respectively). The single and multiple dose regimes delivered comparable serum IgG whereas the single dose yielded better piglet hydration as noted by less weight loss. In conclusion, all colostrum supplements were comparable in delivering absorbable IgG to the neonatal piglet.

Lyophilized bovine colostrum as a source of immunoglobulins and insulin-like growth factor for newborn goat kids

The objective of this study was to evaluate lyophilized bovine colostrum as an alternative source of passive immunity and insulin like growth factor I (IGF-I) for goat kids, considering newborns consuming non-maternal colostrum. Twenty-nine male newborns received 5% of body weight of lyophilized bovine (LBC) or goat colostrum (GC), both with 55mg/mL of IgG, at 0, 7 and 14h of life. Blood samples were collected at 0, 7, 14, 18, 24, 36, 48, 72 and 96h of life to determine serum IgG, total protein (TP), IGF-I and apparent efficiency of IgG absorption at 7, 14, 18 and 24h (AEA7hr, AEA14hr, AEA18hr, AEAtotal, respectively). In LBC, the values of serum IgG at 14, 18, 24 and 48h (13.1, 13.4, 14.1 and 14.6mg/mL, respectively) were higher than the values at 0 and 7h (0.04 and 6.9mg/mL, respectively). In GC, the serum IgG at 18h (9.3mg/mL) was higher than the value at 7h (5.5mg/mL). AEA7hr and AEA14hr in LBC were the same (19.2 and 18.5%, respectively, P>0.05) and the values of AEA18hr and AEAtotal, 9.3 and 9.5%, respectively, were equal and smaller than AEA7hr and AEA14hr. In GC, AEA7hr, 20.8%, was higher than AEA14hr, 16.1% (P<0.05) and AEA18hr and AEAtotal, 9.2 and 8.0%, respectively, were equal and smaller than AEA7hr and AEA14hr. The serum TP and IGF-I were not affected by colostrum feeding. Considering the variables study in the present work, lyophilized bovine colostrum constitutes a promising alternative substitute to goat colostrum in newborn goat kids, since the supply of immunoglobulins and IGF-I was suitable for the kids.

Feeding heat-treated colostrum to neonatal dairy heifers: Effects on growth characteristics and blood parameters

Newborn Holstein heifer calves were studied to compare absorption of immunoglobulin G (IgG1 and IgG2), total serum protein concentration, lymphocyte counts, health scores, growth, and starter intake after receiving unheated or heat-treated colostrum. First-milking colostrum was collected from Holstein cows and frozen at −20°C to accumulate a large batch. After thawing and mixing, half of the colostrum was transferred into 1.89-L plastic containers and frozen at −20°C until needed for feeding. The remaining half was heated at 60°C for 30min, transferred into 1.89-L plastic containers, and then frozen at −20°C until needed for feeding. Forty heifer calves weighing ≥32kg at birth were enrolled into 1 of 2 treatment groups before suckling occurred. For the first feeding, 3.8L of colostrum was bottle fed by 1.5 to 2h of age. For the second and third feedings, pasteurized whole milk at 5% of birth body weight (BW) was fed. Subsequently, calves received milk replacer containing 20% crude protein and 20% fat at 10% of birth BW/d until wk 5. Milk replacer was reduced to 1 feeding of 5% birth BW until weaning at 6 wk of age. Blood samples and growth data were collected through wk 8. Batch heat-treatment of colostrum at 60°C for 30min lowered colostrum bacteria concentration while maintaining colostral IgG concentration and viscosity. Calves fed heat-treated colostrum had significantly greater IgG concentrations at 24h and greater apparent efficiency of IgG absorption (IgG=23.4g/L; apparent efficiency of absorption=33.2%) compared with calves fed unheated colostrum (IgG=19.6g/L; apparent efficiency of absorption=27.7%). There was no difference between treatment groups in growth measurements, calf starter intake, lymphocyte counts, or health scores.

Effects of colostrum replacer supplemented with lactoferrin on the blood plasma immunoglobulin G concentration and intestinal absorption of xylose in the neonatal calf1

The objective of this experiment was to determine the effect of lactoferrin (Lf) supplementation of colostrum replacer (CR) fed as 1 or 2 doses on apparent efficiency of IgG absorption, serum IgG concentrations, and xylose absorption/intestinal development in neonatal Holstein bull calves. Eighty bull calves were assigned to a 2 x 4 factorial arrangement of treatments in a randomized complete block design. Calves used were from the University of New Hampshire (n = 48) or a commercial dairy (n = 32). All calves were fed CR according to manufacturer's recommendations +/- Lf treatment within 90 min of birth. Lactoferrin treatments were 0 (control), 0.5, 1, and 2 g/d of supplemental Lf. At 12 h of age, calves were fed a second feeding of CR +/- supplemental Lf or 2 L of milk replacer +/- supplemental Lf. Calves continued to be fed milk replacer +/- supplemental Lf every 12 h for the duration of study. Blood samples were collected for determination of IgG and total serum protein at 0, 6, 12, 18, 24, and 48 h. Calves, except those fed 1 dose of CR plus 1 or 2 g of Lf, had serum IgG concentrations > or = 10 g/L at 24 h. Lactoferrin supplementation had no effect on serum IgG or total serum protein concentrations. Calves fed 2 doses of CR had greater serum IgG concentrations compared with calves fed 1 dose of CR. Apparent efficiency of absorption of IgG was less in calves fed 2 doses of CR compared with calves fed 1 dose of CR. Lactoferrin supplementation (up to 1 g/d) resulted in decreased apparent efficiency of absorption of IgG. At the sixth feeding (60 +/- 2 h of age), D-xylose (0.5 g/kg BW) was mixed with milk replacer +/- supplemental Lf (n = 48) to determine xylose absorption by the small intestine. Blood was collected at 0, 2, 4, 6, 8, and 12 h after feeding xylose for determination of plasma glucose and xylose concentrations. Xylose means and area under the curve resulted in quadratic effects. Feeding calves 0.5 or 1 g/d supplemental Lf resulted in decreased plasma xylose concentrations compared with calves fed 0 or 2 g/d of supplemental Lf. Colostrum replacer or supplemental Lf did not affect plasma glucose concentrations. This study indicates that supplementing Lf at 0.5 or 1 g/d to calves fed CR has a negative effect on apparent efficiency of IgG absorption and xylose absorption.

Effects of Feeding Heat-Treated Colostrum on Passive Transfer of Immune and Nutritional Parameters in Neonatal Dairy Calves

The first objective of this study was to describe the effect of on-farm heat treatment of colostrum on colostral bacteria counts and IgG concentrations. The second objective was to describe the effect of feeding heat-treated (vs. raw) colostrum on passive transfer of colostral immune and nutritional parameters in neonatal calves. Pooled batches of colostrum were mixed and divided equally: one half was fed raw whereas the other half was fed after heat treatment at 60°C for 60min using a commercial on-farm batch pasteurizer. Colostrum samples were cultured for total bacteria count and total coliform count and analyzed for total IgG concentration. Forty-nine Holstein calves were fed either raw colostrum (n = 24) or heat-treated colostrums (n = 25) within 1 to 2h after birth. Serum samples collected from calves at 0h (precolostrum) and 24h (postcolostrum) were assayed for serum total protein; IgG, IgA, and IgM concentrations; peripheral total leukocyte counts; neutrophil counts; lymphocyte counts; lymphocyte phenotypes; vitamin A, vitamin E, cholesterol, and β-carotene concentrations. Serum samples collected from 2- to 5-d-old calves were tested for immunoglobulin function via a bovine viral diarrhea virus type I serum neutralization titer and for neutrophil bacterial opsonization activity. On-farm batch heat treatment of colostrum at 60°C for 60min resulted in lower colostrum bacteria concentrations while maintaining colostral IgG concentration. Calves fed heat-treated colostrum had significantly greater serum total protein and IgG concentrations at 24h, plus greater apparent efficiency of IgG absorption (total protein = 6.3 mg/dL; IgG = 22.3 mg/mL; apparent efficiency of absorption = 35.6%) compared with calves fed raw colostrum (TP = 5.9 mg/dL; IgG = 18.1 mg/mL; apparent efficiency of absorption = 26.1%). There was no effect of treatment on serum concentrations of IgA, IgM, vitamin A, vitamin E, cholesterol, β-carotene or vitamin E:cholesterol ratio, or on serum bovine viral diarrhea virus type I serum neutralization titers. There was no difference between treatment groups when examining calf plasma total leukocyte counts, neutrophil counts, lymphocyte counts, or neutrophil opsonization activity. However, the latter results were considered inconclusive.