Apparent Efficiency Of Absorption Research Articles

PSIII-11 Impacts of late gestational in utero heat stress on small intestine dynamics of neonatal dairy calves

Abstract Late gestation heat stress in dairy cows has been shown to negatively affect offspring growth and development. In utero heat stressed calves have altered small intestine morphology and an impaired ability to absorb colostral immunoglobulin G (IgG). Thus, the objective of this study was to characterize potential cellular and molecular alterations in the small intestine of neonatal in utero heat stressed calves. In the last ~56 d of gestation pregnant dams were either heat stressed (shade; n = 41) or cooled (shade, fans, soakers; n = 41) resulting in heifers that were in utero heat stressed (IUHS, n = 15) or in utero cooled (IUCL, n = 15). Heifers were fed 3.78 L of high-quality colostrum within 2 h of birth. Apparent efficiency of absorption (AEA) of IgG was calculated by measuring IgG content fed in colostrum and in 24 h serum. Within 4.6 ± 2.3 h of birth a subset of calves (n = 8/treatment) not fed colostrum were euthanized to collect samples from the ileum. Tissue for histological analysis was placed in 10% neutral buffered formalin before being dehydrated, embedded in paraffin, cut into 5 μm thicknesses, and mounted to glass slides. The TUNEL method was used to identify apoptotic cells using the Keyence BZ-X800 Microscope. Tissue for gene expression analysis was snap-frozen and kept at -80°C before RNA extraction and cDNA synthesis. The transcript abundance of endosomal (FCGRT, DAB2, MAMDC4), tight junction (ZO1, ZO2, ZO3, OCLN, CLDN1), and heat shock (HSP90, HSF1) related genes were measured by qPCR using the CFX96 Real-Time PCR detection System (BIO-RAD). Data were analyzed using PROC MIXED or PROC GLIMMIX depending on the response variable. TUNEL results are expressed as the proportion of positive cells to total cells. Quantitative PCR data were analyzed by assessing the estimates of the model relative to the geometric mean of 3 reference genes (ACTB, GADPH, RSP9; ΔΔCT). The concentration of colostrum IgG fed to calves was not different (136.1 vs. 122.5 g/L; IUHS vs. IUCL, respectively; P = 0.32), but AEA of IgG was reduced in IUHS relative to IUCL calves (23.5 vs. 33.3%; P < 0.01). The proportion of apoptotic cells within the villi of the ileum was increased in IUHS calves compared with IUCL (2.11 vs. 1.57%; P < 0.01). Ileum gene transcript abundance of DAB2 and MAMDC4 were increased (P < 0.01), while FCGRT transcripts tended to increase in IUHS calves (P = 0.08). All tight junction and heat shock-related gene transcripts were increased within the ileum of IUHS calves (P ≤ 0.02) with the exceptions of CLDN1 and HSP90, which were not different between treatments (P ≥ 0.22).These results suggest that exposure to heat stress in utero impact small intestine integrity after birth and affect key IgG transporters, providing insight into underlying mechanisms responsible for reduced IgG absorption in IUHS calves.

Difructose Anhydride and Passive Immunity Effects on Passive Immune Transfer and Performance of Feeding Difructose Anhydride to Neonatal Calves.

The objective of this study was to assess the potential effects of supplementing difructose anyhdride III (DFAIII) during the first days of life on the absorption of immunoglobulin G (IgG) and growth performance of calves early in life fed colostrum with a high IgG concentration. Sixty-six healthy new-born Holstein calves were randomly assigned to three treatments consisting of no supplementation (control), supplementation of 12 g/d (DFA12), or 36 g/d (DFA36) of DFAIII during the first 7 d of life via colostrum and milk replacer (MR). Calves were separated from dams at birth and bottle-fed colostrum in two meals, each targeting 2.5 L within the first 18 h of birth. Colostrum had been previously collected from other dams (and preserved frozen) within the first 2 h of calving and had a Brix value ≥32%. Daily consumption of starter concentrate and MR (and colostrum on the first day) were individually monitored. Calves were body weighed using an electronic scale at birth and on a weekly basis thereafter until the end of study at 42 d of age. A sample of colostrum fed to each calf and a blood sample from the jugular vein of the calves were collected at 12 and 24 h of life to determine the IgG concentration. The mean colostrum IgG concentration fed in the current study was 110 ± 33.7 g/L (mean ± SD). No differences in animal performance were found among the treatments. Calves on all treatments consumed the same amount of colostrum with a similar concentration of IgG, and thus the amount of IgG consumed was also similar. Serum IgG concentrations were greater at 24 than at 12 h but did not differ among treatments. However, the apparent efficiency of absorption of colostral immunoglobulins was greater in DFA12 and DFA36 at 12 h of life than in control calves, with no differences observed at 24 h. Even when feeding high-quality colostrum, in terms of IgG concentration, supplementation with difructose anhydride III may pose an additional advantage in promoting the passive transfer of immunoglobulins in neonatal Holstein calves during the first 12 h of life.

Colostrum insulin supplementation does not influence immunoglobulin G absorption in neonatal Holstein bulls

Since insulin has been demonstrated to suppress IgG absorption in other neonatal species, we had the objective to delineate how colostral insulin concentrations affect IgG absorption in neonatal bovines. We enrolled Holstein bull calves (n = 48; body weight = 46.3 ± 0.84 kg) at birth and randomized them by birth order to receive (1) colostrum that contained basal insulin concentrations (12.9 μg/L; n = 16), or colostrum that had been supplemented with an exogenous insulin to increase the insulin concentration to either (2) 5 times (70.0 μg/L; n = 16) or (3) 10 times (149.7 μg/L; n = 16) that of the basal colostrum. Gross colostrum composition (crude fat: 4.1 ± 0.06%; crude protein: 11.7 ± 0.05%; lactose: 1.9 ± 0.01%; IgG: 63.9 ± 1.19 g/L) was similar between treatments and calves were fed (7% body weight, 3.1 ± 0.06 L) their treatments at 2, 14, and 26 h postnatal. Serum was collected at 0, 30, 60, 90, 120, 180, 240, 360, 480, and 600 min postprandial respective to the first and second colostrum feeding and analyzed for IgG concentration. The incremental area under the curve (I-AUC) and apparent efficiency of absorption (AEA) were calculated for the 10-h periods following the first and second colostrum meal. Serum IgG concentrations over time, I-AUC, and AEA were statistically analyzed as a complete randomized design. Colostrum insulin concentration did not affect serum IgG concentrations or the I-AUC or AEA after calves were fed colostrum at 2 and 14 h postnatal. High colostral insulin content is not detrimental or promotive to IgG absorption in neonatal Holstein bulls.

Effects of enriching IgG concentration in low- and medium-quality colostrum with colostrum replacer on IgG absorption in newborn Holstein calves

Ingestion and absorption of greater quantities of IgG are required to increase serum IgG levels in newborn calves. This could be achieved by adding colostrum replacer (CR) to maternal colostrum (MC). The objective of this study was to investigate whether low and high-quality MC can be enriched with bovine dried CR to achieve adequate serum IgG levels. Male Holstein calves (n = 80; 16/treatment) with birth body weights (BW) of 40 to 52 kg were randomly enrolled to be fed 3.8 L of the following combinations: 30 g/L IgG MC (C1), 60 g/L IgG MC (C2), 90 g/L IgG MC (C3), C1 enriched with 551 g of CR (60 g/L; 30-60CR), or C2 enriched with 620 g of CR (90 g/L: 60-90CR). A subset of 40 calves (8/treatment) had a jugular catheter placed and were fed colostrum containing acetaminophen at a dose of 150 mg/kg of metabolic body weight, to estimate abomasal emptying rate per hour (kABh). Baseline blood samples were taken (0 h), followed by sequential samples at 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, and 48 h relative to initial colostrum feeding. Results for all measurements are presented in the following order, unless otherwise stated: C1, C2, C3, 30-60CR, and 60-90CR. Serum IgG levels at 24 h were different among calves fed C1, C2, C3, 30-60CR, and 60-90CR: 11.8, 24.3, 35.7, 19.9, and 26.9 mg/mL ± 1.02 (mean ± SEM), respectively. Serum IgG at 24 h increased when enriching C1 to 30-60CR, but not from C2 to 60-90CR. Similarly, apparent efficiency of absorption (AEA) values for calves fed C1, C2, C3, 30-60CR, and 60-90CR were different: 42.4, 45.1, 43.2, 36.3, and 33.4% ± 1.93, respectively. Enriching C2 to 60-90CR reduced AEA, and enriching C1 to 30-60CR tended to decrease AEA. The kABh values for C1, C2, C3, 30-60CR, and 60-90CR were also different: 0.16, 0.13, 0.11, 0.09, and 0.09 ± 0.005, respectively. Enriching C1 to 30-60CR or C2 to 60-90CR reduced kABh. However, 30-60CR and 60-90CR have similar kABh compared with a reference colostrum meal (90 g/L IgG, C3). Even though kABh was reduced for 30-60CR, results indicate that C1 has the potential to be enriched and achieve acceptable serum IgG levels at 24 h without affecting AEA.

Association of a green tea extract with serum immunoglobulin G status and neonatal vitality in newborn dairy calves.

Poor vigor at birth has been associated with reduced IgG absorption from colostrum and a reduced vitality in neonatal dairy calves. Some natural compounds, such as green tea extract, may improve vitality in compromised calves. The objective of this randomized controlled trial was to evaluate the potential of supplementing a green tea extract (15 mL) to calves to improve vigor and activity behavior for the first 72 h postnatal. Also, this study aimed to investigate the influence of green tea extract supplementation on calf serum IgG concentration and the apparent efficiency of absorption (AEA) of colostral IgG. Holstein calves (n = 24) weighing 42.49 ± 1.07 kg postnatal received a complete random assignment at 3 h of one 15-mL dose of green tea extract (Calf Perk, TechMix) or distilled water orally before tube feeding colostrum replacer (Premolac Plus IgG, Zinpro) at 4 h postnatal. Two observers assessed for calving time and dystocia by live video stream to retrieve all calves within 2 h postnatal. One veterinarian performed a baseline vigor assessment based on heart rate and response to stimuli on all calves at 2.5 h, before colostrum feeding at 3.75 h, as well as at 24, 48, and 72 h postnatal. Calf blood samples were taken to assess total IgG by radial immunodiffusion assay at 2.5, 6, 12, 24, 48, and 72 h. Calf vitality was also observed continuously by video for all calves to determine whether treatment was associated with attempts to stand, lying time, and exploration of their pen environment for the first 24 h. We used an ordinal logistic model to evaluate the odds of green tea extract improving a calf's vigor category from 2.5 h postnatal to 72 h of age. Vigor score was categorized as abnormal (≤4), average (5), or alert (≥6), with hour as a fixed effect. We also ran mixed linear models to evaluate the effect of extract on total IgG and AEA, with time and dystocia as fixed effects. Five dystocia calves were enrolled (2 control, 3 extract), but assistance was minor (e.g., manual assistance and all were assisted within 1 h). Baseline vigor scores and baseline total IgG were not different between groups. Vigor score category was not associated with green tea extract supplementation (odds ratio 1.17; 95% CI: 0.43-3.15) but increased with time compared with controls. We observed no association of treatment with total IgG or AEA in the calves, suggesting green tea extract does not compromise IgG absorption. Calf vitality, lying behavior, and exploratory behavior were not associated with green tea extract treatment. Our findings suggest that green tea extract supplementation does not affect AEA and serum IgG concentration in calves. Future research should evaluate whether green tea extract improves vitality in calves experiencing severe dystocia.

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.

Effects of maternal choline supplementation on performance and immunity of progeny from birth to weaning.

The objectives were to investigate whether supplementation with rumen-protected choline (RPC) during late pregnancy in Holstein cows affects offspring immunity and growth, and whether effects are utero-placental, colostrum dependent, or both. A total of 105 multiparous Holstein cows were assigned randomly to a prepartum diet (1.54 Mcal of NEL/kg of DM, and 15.8% CP) without (control) or with added RPC (12.9 g/d of choline ion). Calves (n = 111) were blocked by sex and assigned randomly to colostrum from control cows or colostrum from RPC cows, resulting in 4 treatments in a 2 × 2 factorial arrangement: (1) calves born and fed colostrum from non-supplemented dams (NN; n = 33); (2) calves from non-supplemented dams and fed colostrum from RPC-fed cows (NC; n = 25); (3) calves from RPC-supplemented dams and colostrum from non-supplemented cows (CN; n = 28); and (4) calves from RPC-supplemented dams and colostrum from RPC-fed cows (CC; n = 25). Growth, intakes, and immunity of females were evaluated up to 56 d of age. Growth and intake of male calves was evaluated up to 35 d of age, and physiological and immune responses to intravenous LPS challenge were evaluated from 21 to 35 d of age. Effects of prenatal and colostrum treatments and interactions between treatments were analyzed using mixed models. Calves fed colostrum from RPC-supplemented dams had a 17.4% increase in apparent efficiency of absorption of IgG compared with calves fed colostrum from control dams (27.4 vs. 23.3%). Incidence of fever in the first 21 d of age tended to be less in females born from RPC-supplemented dams compared with females born from control dams (31 vs. 58%). Prenatal RPC females had increased hematocrit and concentrations of red blood cells, leukocytes, neutrophils, and lymphocytes in blood compared with prenatal females born from control dams. Compared with prenatal control females, prenatal RPC females had greater intake of milk replacer (704 vs. 748 ± 9.9 g/d) and starter (45.4 vs. 60.2 ± 5.9 g/d) during the first 21 d of age. In male calves, mean intake of DM was greater (1,074 vs. 976 ± 45 g/d) after the LPS challenge (0 to 8 d) by calves born from dams fed RPC compared with males born from control dams. Calves born from RPC-fed dams also had lower mean rectal temperature (39.0 vs. 39.2°C) and mean respiration rate (35.6 vs. 39.3 breaths/min) compared with males born from control dams. Moreover, serum concentrations of metabolites (i.e., β-hydroxybutyric acid, fatty acids, and glucose), cytokines (i.e., tumor necrosis factor-α) and acute phase proteins (i.e., serum amyloid A) were consistent with less-severe inflammatory response to LPS in males born from dams fed RPC compared with control. Source of colostrum and interaction between prenatal and colostrum treatments had minimal effects on calf responses to LPS. Overall, maternal RPC supplementation during late gestation suggests a positive effect on immunity, in that colostrum from RPC-fed dams increased efficiency of IgG absorption and maternal supplementation with RPC during late gestation, regardless of colostrum source, attenuated responses to LPS.

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 a low- or high-frequency colostrum feeding protocol on immunoglobulin G absorption in newborn calves

Calves might experience an upper limit of IgG absorption from colostrum ingestion at birth, but it is not clear whether the total IgG mass fed in the first meal or feeding frequencies can saturate the IgG transport mechanism and therefore limit IgG absorption. The objective of this study was to determine whether different colostrum replacer (CR) feeding frequencies affect serum IgG levels or apparent efficiency of absorption (AEA) in neonatal calves. Male Holstein calves (n = 40) were separated from their dams immediately after parturition and randomly assigned to receive CR [12% of birth body weight (BW)], following either (1) a low-frequency (LF; n = 20) or (2) a high-frequency (HF; n = 20) feeding protocol. Low-frequency calves received 2 CR meals (8% and 4% birth BW within 1 h after birth and 12 h after first CR feeding, respectively), whereas HF calves received 3 CR meals (4% of BW for each meal; within 1 h after birth, 6, and 12 h after first CR feeding). The CR powder fed had a dry matter IgG concentration of 30% and an IgG concentration of 70.5 g/L when reconstituted. All CR was fed via esophageal tube within 1 h after birth. Calves were bottle-fed pasteurized milk (5% birth BW) at 24, 36, and 48 h after the first CR feeding. Blood was collected before first CR feeding and at the following intervals post-CR feeding: every 2 h until 18 h; every 3 h from 18 to 30 h; and every 6 h from 30 to 48 h after the first CR feeding. Serum IgG values at 24 h did not differ between LF and HF (25.79 ± 0.93 and 25.66 ± 0.88 g/L, respectively). In the first meal, calves fed LF ingested a higher total IgG mass than HF (257.98 ± 4.16 g and 126.72 ± 4.05 g, respectively); however, AEA at 24 h did not differ for calves fed HF or LF (27.68 ± 1.16% and 27.63 ± 1.26%, respectively). The IgG area under the curve (AUC) at 24 h was greater for calves fed LF than HF (443.13 ± 15.17 and 379.59 ± 13.99 g of IgG/L × h, respectively). Additionally, AUC at 6 h, 12 h, and 48 h were greater for calves fed LF than HF. These results indicate that, although LF calves had a greater AUC, HF calves were still able to absorb IgG in the second and third meal, allowing HF calves to achieve serum IgG levels similar to those of LF calves at 24 h. In addition, the provision of 3 meals at 70.5 g/L of IgG within the first 12 h of life did not result in added benefits to serum IgG or AEA levels.

Absorption of colostral immunoglobulin G by Icelandic dairy calves

Serum samples were taken from 11 Icelandic dairy calves, at birth and 24 hours later, and 11 colostrum samples were taken from their mothers with the concentration of IgG measured by ELISA. The amount of colostrum ingested by each calf was also measured. The results showed that the mean concentration of IgG in cow colostrum at birth was 11.54 mg ml-1. The mean concentration in the serum of calves that had ingested known quantities of colostrum was 8.02 mg ml-1 24 hours postpartum. Both values were lower than described in other cattle breeds. Significant correlation existed between the amount of colostral IgG consumed and serum concentration of IgG in the calves 24 hours postpartum. The mean apparent efficiency of absorption (AEA) was 43%, which is high compared to other studies. Although the study group was small, the results give an indication of the ability of Icelandic calves to absorb colostral IgG.

Late-Gestation in utero Heat Stress Limits Dairy Heifer Early-Life Growth and Organ Development

Dairy calves exposed to late-gestation heat stress weigh less, have impaired immunity, produce less milk across multiple lactations, and have reduced productive life. However, less is known about the relationship between in utero heat stress and organ morphology and development. Herein, we characterized the consequences of late-gestation in utero heat stress on body and organ growth trajectories during early-life development. Holstein heifers were either in utero heat-stressed (IU-HT, n = 36, dams exposed to THI &amp;gt; 68) or cooled (IU-CL, n = 37, dams exposed to THI &amp;gt; 68 with access to active cooling) during late gestation (54 ± 5 d prepartum). All heifers were reared identically from birth to weaning. Upon birth, calves were weighed and fed 3.78 L of colostrum followed by 0.87 kg DM/d milk replacer (MR) over two feedings and ad libitum starter concentrate daily. Weaning began at 49 d and ended at 56 d of age. Feed intake was recorded daily, and body weight (BW) and other growth measures were recorded at 0, 28, 56, and 63 d. Blood was collected at d 1 then weekly. Subsets of heifers were selected for euthanasia at birth and 7 d after complete weaning (n = 8 per group each) to harvest and weigh major organs. Reduced BW and stature measures persisted in IU-HT heifers from 0 to 63 d of age with a 7% lower average daily gain and reduced starter consumption relative to IU-CL heifers. IU-HT heifers had lower hematocrit percentages and reduced apparent efficiency of absorption of IgG relative to IU-CL heifers. Additionally, IU-HT heifers had reduced gross thymus, spleen, thyroid gland, and heart weight at birth and larger adrenal glands and kidneys but smaller ovaries relative to BW at 63 d. The mammary gland of IU-HT heifers was smaller relative to IU-CL heifers at birth and 63 d adjusted for BW, suggesting mechanisms leading to impaired milk yield in mature IU-HT cows are initiated early in development. In summary, in utero heat stress reduces whole-body size and limits development of key organs with potential repercussions on dairy calf metabolic adaptation, immune function, and future productivity.

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.

Effect of late-gestation heat stress in nulliparous heifers on postnatal growth, passive transfer of immunoglobulin G, and thermoregulation of their calves

Youngstock such as nulliparous pregnant dairy heifers are not typically considered for active cooling, as they are thought to be more heat tolerant than mature cows. Recently, the benefits of heat stress abatement in pregnant heifers were studied, but the effect of in utero hyperthermia on the calf is still unknown. Herein, we aimed to investigate the effects of late-gestation heat stress in nulliparous heifers on the growth, immune, and thermoregulatory responses of their calves. Pregnant nulliparous dams were randomly selected for either active cooling (CL; fans and soakers; n = 15) or heat stress (HT; n = 16) 60 d before expected calving. After birth, respiration rate, rectal temperature, skin temperature, and sweating rate were obtained from their heifer calves at 24 h and on d 14, 28, 42, and 56. Blood samples and body weights were both collected for measurement of total protein and hematocrit and calculation of average daily gains, respectively. Gestation length was shorter in HT heifers (272 vs. 276 ± 1.28 d) relative to CL heifers. Birth weights, weaning weights, body weights up to d 56, and average daily gain from birth to weaning were not different between in utero HT (IUHT; n = 13) and in utero CL (IUCL; n = 12) calves. Apparent efficiency of absorption of immunoglobulin G tended to be lower in IUHT calves (26.3 vs. 42.7 ± 9.0%), and serum IgG concentrations from birth to d 56 were significantly lower in IUHT calves relative to IUCL calves (22.0 vs. 32.4 ± 4.47 g/L). Postnatal respiration rate, rectal temperature, sweating rate, total protein, and hematocrit were not different between in utero treatments. There was a tendency for IUHT calves to have lower skin temperature at 24 h (34.9 vs. 36.9 ± 1.05°C), and skin temperature tended to be elevated in IUHT calves at d 56 (29.6 vs. 27.9 ± 1.05°C). In summary, the lack of heat stress abatement during late gestation reduces gestation length of nulliparous heifers. Additionally, providing active cooling to nulliparous heifers during the prepartum period confers immune benefits to their offspring, although it does not translate to growth improvements.

PSVI-21 Evaluation of passive immunity transfer and performance of calves receiving different sources of immunoglobulins

Abstract The efficiency in the passive immunity transfer (PIT) is directly associated with the production cost and productivity of the animals. When fresh maternal colostrum (FC) is not available, frozen colostrum or colostrum replacer (CR) are alternatives to avoid failures in PIT (FPIT). Thirty-nine Holstein calves were used in a randomized block design with gender, weight and date of birth as blocking effect, and distributed in treatments: 1) feeding of 10% BW of CF; 2) feeding of 10% BW of FC; 3) 1.5 dose of a CR (SCCL®, Saskatoon, Canada). Animals received 6L/d of milk until 56d of life when they were subjected to gradual weaning until the end of the study (63d). Feed intake and health was monitored daily, and weight and blood samples were weekly taken. The Brix value at 24h of life was higher in animals receiving maternal colostrum when compared to CR (FC: 9.52a; Frozen: 10.68a; CR: 8.23b; P &amp;lt; 0.01). The immunoglobulins intake was higher (P &amp;lt; 0.01) for calves fed with maternal colostrum (FC or Frozen), which may explain the differences observed in the apparent efficiency of absorption (P = 0.02). The colostrum protocols affected the serum IgG concentration assessed at 24h (FC: 26.65b; Frozen: 35.69a; CR: 16.93c; P &amp;lt; 0.01); however, no treatment resulted in FPIT, with values of serum IgG above 10g/L. Starter intake increased during the milk-feeding period (P &amp;lt; 0.01), with no effects of colostrum feeding. ADG was influenced by treatments (P = 0.01), with higher gains for calves fed FC, resulting in higher final BW (P = 0.04). During the milk-feeding period, plasma glucose and total serum protein were higher for FC than for CR calves, with no differences for calves fed frozen colostrum. Feeding FC resulted in heavier animals at weaning; however, the frozen colostrum and CR used in this study are adequate alternatives, with no FTIP observed.

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.

Feeding colostrum or a 1:1 colostrum:whole milk mixture for 3 days after birth increases serum immunoglobulin G and apparent immunoglobulin G persistency in Holstein bulls

Conflicting reports exist on whether prolonged IgG consumption can further increase serum IgG in neonatal calves. Given that higher serum IgG in neonates has lifelong benefits, our objective was to determine whether serum IgG can be increased by providing multiple meals containing IgG to neonatal calves. Twenty-seven Holstein bulls were all fed 1 colostrum meal (7.5% body weight; 62 g of IgG/L) at 2 h after birth and randomly assigned to be fed (5% body weight) colostrum (COL; n = 9), whole milk (WM; n = 9), or a 1:1 colostrum:whole milk mixture (MX; n = 9) every 12 h from 12 to 72 h. Serum IgG was measured at 1, 2, 3, 6, 9, 11, and 12 h after birth. After the 12-h meal, IgG was determined at 0.5-h intervals until 16 h and then at 1-h intervals from 16 to 24 h. Serum IgG was then measured at 27 h, then every 6 h from 30 to 60 h. From 60 to 64 h, IgG was measured every 0.5 h, then at 65 and 66 h, and then every 2 h until 72 h. Serum IgG increased rapidly between 2 and 12 h for all calves. A treatment × time interaction occurred as serum IgG began to diverge between treatments after they were fed at 12 h; the interaction was greatest over the entire period for COL compared with both MX and WM and was greater for MX than for WM. Maximum IgG concentrations (Cmax) were 30.4 ± 0.8, 27.2 ± 0.8, and 23.9 ± 0.8 g/L for COL, MX, and WM, respectively. Although MX Cmax was equivalent to both COL and WM Cmax, COL Cmax was greater than WM Cmax. Feeding COL and MX also prolonged the time to reach Cmax. Respectively, these calves achieved Cmax at 29.5 and 27.0 ± 3.4 h, whereas WM IgG peaked at 13.4 ± 3.4 h. No differences were observed for apparent efficiency of absorption between treatments from 0 to 12 h and 0 to 24 h. Immunoglobulin G area under the curve (AUC) was the same for COL and MX calves over the entire experimental period and from when treatments were fed. The IgG AUC for 0 to 72 h for WM calves was 27.4% lesser than that for COL calves but not different from MX calves. However, the IgG AUC for 12 to 72 h for WM calves differed relative to that for both COL (30.8% less) and MX (19.6% less) calves. Serum IgG concentrations were more persistent when COL (88.2 ± 2.4%) and MX (91.2 ± 2.4%) were fed rather than WM (75.3 ± 2.4%). Prolonged IgG consumption increased serum IgG concentrations, corresponding to the mass of IgG fed, and improved apparent IgG persistency in Holstein bulls. Neonatal calves should be fed at least 62 g of IgG at 12 h after birth to further increase serum IgG concentrations.

The effect of meloxicam on neonatal dairy calves: Immunoglobulin G uptake and preweaning performance

Objectives of this study were to determine effects of meloxicam administered in 2 forms on IgG uptake, growth, and health of preweaned calves. Sixteen Holstein bulls and 14 heifers with a body weight (BW) of 44.3 ± 5.24 kg were blocked by birth date in a randomized complete block design. Calves were removed from the dam before suckling, weighed, and randomly assigned to 1 of 3 treatments: (1) colostrum replacer (CR) at 0 h with no meloxicam (control; CON), (2) 1 mg/kg of BW of meloxicam in pill form before CR (PL), or (3) 1 mg/kg of BW of meloxicam mixed in solution with CR (SL). Calves were fed 675 g of dry matter of CR, providing a volume of 3 L and 180 g of IgG. Blood samples were collected at 0 h to analyze initial IgG and ketone concentrations, and at 6, 12, 18, and 24 h to analyze IgG uptake. At 24 h, calves were fed 432 g of dry matter of 24% crude protein milk replacer (MR) split in 2 feedings, and free choice starter and water until 42 d. Weekly blood samples were analyzed for glucose, plasma urea nitrogen, and ketone concentrations. Time of consumption of MR, BW, length, hip and withers height, and heart girth were recorded weekly. All calves achieved adequate transfer of immunity. Meloxicam did not affect apparent efficiency of absorption, serum total protein, or IgG uptake at 6, 18, and 24 h; however, meloxicam-treated calves had lesser IgG concentrations at 12 h (24.40 and 22.59 g/L for PL and SL, respectively) compared with CON (28.47 g/L). Meloxicam treatment did not affect BW. Calves that received PL tended to gain length at a faster rate (0.24 cm/d) than those that received SL (0.19 cm/d). Meloxicam treatment did not affect MR intake, time of consumption of MR, total dry matter intake, or feed efficiency. Meloxicam-treated calves tended to consume more starter (560.4 and 515.4 g/d for PL and SL, respectively) than those that received CON (452.6 g/d). Ketone levels tended to be greater in meloxicam-treated calves (0.15 and 0.17 mmol/L for PL and SL, respectively), suggesting improved rumen development compared with those that received CON (0.12 mmol/L). Meloxicam treatment did not affect plasma urea nitrogen . Glucose concentrations of calves that received PL (73.2 mg/dL) were less than those that received SL (83.3 mg/dL). Results of this study suggest that meloxicam given at 0 h offers positive effects on starter intake, and possibly rumen development, of preweaned dairy calves. Treatment PL, as compared with SL, offered positive results for rumen development, indicated by lower blood glucose levels.

Evaluation of Immunoglobulin G Absorption from Goat Colostrum by Newborn Piglets.

Simple SummaryAlternatives to sow colostrum are necessary to ensure adequate colostrum intake by piglets born from hyperprolific sows. This study was conducted to evaluate whether piglets can absorb goat immunoglobin G (IgG) and study its effects on piglets. The results showed that piglets absorbed goat IgG with an apparent coefficient of absorption of 20.9%. In addition, the piglets tolerated goat colostrum well, opening up the possibility of developing supplements based on goat colostrum for newborn piglets.The aim of this study was to evaluate whether piglets absorb immunoglobin G (IgG) from goat colostrum and the potential effects of its ingestion on suckling piglets. Thirty-eight piglets with body weights ranging from 1000 to 1700 g were assigned to one of the three experimental treatments: Control group (C), where piglets were allowed to suckle normally, and porcine and goat groups. The piglets from the last two groups were removed from the sows after birth and received an oral 20 mL dose every 3 h of porcine (PC) or goat colostrum (GC), respectively, during first 12 h of life. Then, they were returned to newly farrowing sows to continue suckling until 20 d. The apparent efficiency of absorption (AEA) of IgG at 12 h was calculated as total serum IgG divided by ingested IgG. No diarrhea or symptoms of intolerance were observed at any time. On day 20, body weight and the number of dead piglets were similar in all three treatments (p > 0.05). At 12 h, the concentration of goat IgG in the serum of piglets fed GC was 8.11 mg/mL. AEA was 20.9% for goat IgG and 26.3% for porcine IgG (p > 0.05). Therefore, goat colostrum seems a promising alternative to study new feed supplements or artificial rearing of newborn piglets.