Late gestation supplementation of corn dried distiller's grains plus solubles to beef cows fed a low-quality forage: III. effects on mammary gland blood flow, colostrum and milk production, and calf body weights

Thermotolerance capabilities, blood metabolomics, and mammary gland hemodynamics and transcriptomic profiles of slick-haired Holstein cattle during mid lactation in Puerto Rico

Holstein cattle carrying a prolactin receptor gene mutation (SLICK) exhibit short and sleek hair coats (short-haired Holstein [SLK]) enhancing thermotolerance and productivity compared with wild type-haired Holstein (WT) under tropical conditions. The objectives were to unravel the physiological and molecular mechanisms that confer an advantage to this slick genotype in Puerto Rico and determine potential correlations between metabolites and physiological variables. At 160 ± 3 DIM we compared vaginal temperatures (VT) and voluntary solar radiation exposure (VSRE) during 48 h between 9 SLK and 9 WT Holsteins, whereas a subsample of 7 SLK and 7 WT were used to assess udder skin temperature, mammary gland hemodynamics and transcriptomics, and blood plasma untargeted metabolomics at a single time point. The SLK cattle showed lower VT throughout the day and greater VSRE at 1000 h and 1100 h compared with their WT counterparts. Total mammary blood flow (MBF) was greater in SLK Holsteins compared with WT. The metabolite 9-nitrooctadecenoic acid was identified as a potential biomarker for MBF; moreover, SLK cattle had greater amounts of this metabolite in their plasma. Prostaglandin D2 synthase (PTGS) was upregulated in the slick mammary gland, while plasma prostaglandin D2 was positively correlated with milk yield and increased in SLK Holsteins compared with WT. Interestingly, the arachidonic acid metabolism pathway was enriched in the mammary gland transcriptome and perturbed in the blood metabolome in the SLK Holsteins. In conclusion, SLK Holsteins exhibited lower body temperatures, greater VSRE, enhanced blood supply to the mammary gland, and alterations in genes and metabolites involved in arachidonic acid metabolism at the mammary gland and blood plasma. The usage of the SLK Holstein cattle genetics in dairy operations could be a feasible alternative to mitigate the adverse consequences of heat stress.

Nutrient restriction during late gestation reduces milk yield and mammary blood flow in lactating primiparous beef females

Fall-calving primiparous beef females [body weight (BW): 451 ± 28 (SD) kg; body condition score (BCS): 5.4 ± 0.7] were individually-fed 100% (control; CON; n = 13) or 70% (nutrient restricted; NR; n = 13) of estimated metabolizable energy and metabolizable protein requirements from day 160 of gestation to calving. Post-calving, all dams were individually-fed tall fescue hay supplemented to meet estimated nutrient requirements for maintenance, growth, and lactation until day 149 of lactation. Four-hour milk yields were collected on days 21, 42, 63, 84, 105, and 147 of lactation, and milk nutrient composition was determined. Doppler ultrasonography of both pudendoepigastric arterial trunks was conducted every 21 d from days 24 to 108 of lactation. Total mammary blood flow was calculated, and hemodynamics from both sides were averaged. Data were analyzed as repeated measures with nutritional plane, day of lactation, their interaction, calving date, and calf sex (if P < 0.25) as fixed effects. We previously reported that post-calving, NR dams weighed 64 kg less and were 2.0 BCS lower than CON, but calf birth weight was not affected. Milk weight and volume were 15% less (P = 0.04) for NR dams than CON. Milk protein concentration was lower (P = 0.008) for NR dams than CON, but triglyceride and lactose concentrations were not affected (P ≥ 0.20) by nutritional plane. Milk urea N concentration of NR dams tended to be greater (P = 0.07) on day 42 but was lower (P = 0.01) on day 147 of lactation than CON. Total milk protein, triglyceride, and lactose yields were less (P ≤ 0.05) for NR dams than CON. Total milk urea N yield was less (P ≤ 0.03) for NR dams than CON on days 21, 63, and 147 of lactation. Maternal heart rate was greater (P = 0.008), but pudendoepigastric arterial trunk peak systolic velocity, resistance index, and cross-sectional area were less (P ≤ 0.04) and pulsatility index tended to be less (P = 0.06) for NR dams than CON. Mammary blood flow was 19% less (P = 0.004) for NR dams than CON, but mammary blood flow relative to milk weight or dam BW was not affected (P ≥ 0.14) by nutritional plane. Most milk yield, milk nutrient composition, and mammary blood flow variables were affected (P ≤ 0.04) by day of lactation. In summary, first-parity beef females that were nutrient restricted during late gestation and then fed to meet estimated nutrient requirements during lactation had decreased milk nutrient yield and a similar reduction in mammary blood flow.

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

The objective of this study was to analyze if maternal supply of rumen-protected protein during the dry period can affect the IgG concentration and microbial composition of colostrum and the IgG absorption and fecal microbial composition in the calf. Seventy-four multiparous Holstein Friesian (HF) dairy cows were stratified per parity and randomly assigned to one of 2 different dry period diets, a diet with a low crude protein (CP) level (LP) and a diet with a high CP level (HP) by addition of rumen-undegraded protein (RUP; formaldehyde-treated soybean meal, Mervobest, Nuscience, Drongen, Belgium). Colostrum was collected within 1 h after calving and IgG concentration was quantified by radial immunodiffusion analysis. Forty-nine calves (23 female and 26 male) were enrolled in the trial with a 2 × 2 factorial design, with prenatal and postnatal treatment as the 2 independent variables. This led to 4 experimental groups: LPLP, LPHP, HPLP, and HPHP, in which the first 2 letters refer to the prenatal treatment (diet of the dam) and the last 2 refer to the postnatal treatment (diet of the colostrum-producing cow). Calves received 3× 2 L of colostrum within 2, 6, and 24 h after birth. Meconium and feces were collected solely from female calves (n = 18) by digital palpation of the rectum, immediately after birth and before colostrum administration and at d 3 of age. Microbial DNA was extracted from meconium (n = 9), feces (n = 15), and colostrum (n = 49). Amplicon sequencing of the bacterial V3-V4 region of the 16S rRNA gene was performed for characterization of the bacterial communities. Colostrum IgG concentration was higher in cows that were supplemented with RUP, especially in cows entering their second lactation (LSM ± SEM 61.3 ± 2.3 vs. 55.2 ± 2.8 g of IgG/L). Calves born out of LP cows that received colostrum from HP cows (LPHP) had a lower serum IgG level compared with HPHP and LPLP calves (LSM ± SEM 14.2 ± 1.3 vs. 18.8 ± 1.2 and 20.9 ± 1.3 g of IgG/L in HPHP and LPLP, respectively). The most abundant phyla in colostrum were Proteobacteria (48.2%), Firmicutes (24.8%), Bacteroidetes (9.5%), and Actinobacteria (5.0%). The most abundant phyla in calf meconium and feces were Firmicutes (42.5 and 47.5%), Proteobacteria (21.7% and 33.7%), Bacteroidetes (16.8% and 15.7%), and Actinobacteria (2.9% and 3.1%). There was no difference in the overall microbial communities between colostrum from HP and LP cows. However, 2 genera (both members of the family Lachnospiraceae) were more abundant in colostrum from HP cows compared with LP cows. The microbial composition of meconium, feces and colostrum differed from each other. Fecal samples were more similar to each other and are characterized by a lower intersample diversity compared with colostrum and meconium samples. To conclude, increasing the CP level by addition of RUP in the dry period diet affected the colostrum IgG concentration and the transfer of passive immunity, but did not change the overall microbial composition of colostrum nor of meconium and feces in the calf.

Late gestational nutrient restriction in primiparous beef females: nutrient partitioning among the dam, fetus, and colostrum during gestation

Fall-calving primiparous crossbred beef females [body weight (BW): 451 ± 28 (SD) kg; body condition score (BCS): 5.4 ± 0.7] were allocated by fetal sex and expected calving date to receive either 100% (control; CON; n = 13) or 70% (nutrient restricted; NR; n = 13) of metabolizable energy and metabolizable protein requirements for maintenance, pregnancy, and growth from day 160 of gestation to calving. Heifers were individually-fed chopped poor quality hay and supplemented to meet targeted nutritional planes based on estimated hay intakes. Dam BW, BCS, backfat, and metabolic status were determined pre-treatment, every 21 d (BW and metabolic status) or 42 d (BCS and backfat) during gestation, and post-calving. At birth, calf BW and size were measured, and total colostrum from the most full rear quarter was collected pre-suckling. Data were analyzed with nutritional plane, treatment initiation date, and calf sex (when P < 0.25) as fixed effects. Gestational metabolites included day and nutritional plane × day as repeated measures. During late gestation, CON dams gained (P < 0.01) maternal (non-gravid) BW and maintained (P ≥ 0.17) BCS and backfat, while NR dams lost (P < 0.01) maternal BW, BCS, and backfat. Circulating glucose, urea N, and triglycerides were less (P ≤ 0.05) in NR dams than CON at most late gestational timepoints after treatment initiation. Circulating non-esterified fatty acids were greater (P < 0.01) in NR dams than CON. Post-calving, NR dams weighed 63.6 kg less (P < 0.01) and were 2.0 BCS less (P < 0.01) than CON. At 1 h post-calving, NR dams had less (P = 0.01) plasma glucose and tended to have less (P = 0.08) plasma triglycerides than CON. Nutrient restriction did not affect (P ≥ 0.27) gestation length, calf birth weight, or calf size at birth. Colostrum yield was 40% less (P = 0.04) in NR dams than CON. Protein and immunoglobulin concentrations were greater (P ≤ 0.04), but free glucose and urea N concentrations were less (P ≤ 0.03), in colostrum of NR dams than CON. Colostrum total lactose, free glucose, and urea N were less (P ≤ 0.03) in NR dams than CON, but total protein, triglycerides, and immunoglobulins were not affected (P ≥ 0.55). In summary, beef heifers experiencing late gestational nutrient restriction prioritized partitioning nutrients to fetal growth and colostrum production over maternal growth. During undernutrition, fetal and colostral nutrient demands were largely compensated for by catabolism of maternal tissue stores.

Maternal nutrient restriction during late gestation reduces vigor and alters blood chemistry and hematology in neonatal beef calves

Fall-calving primiparous beef females [body weight: 451 ± 28 (SD) kg; body condition score: 5.4 ± 0.7] were individually-fed either 100% (control; CON; n = 13) or 70% (nutrient restricted; NR; n = 13) of metabolizable energy and metabolizable protein requirements for maintenance, pregnancy, and growth from day 160 of gestation to parturition. Calves were reared naturally by their dams and monitored for latency times from birth to first sternal recumbency, attempt to stand, and stand; vigor scores were assigned at 2, 5, 10, and 20 min of age. Rectal temperatures and jugular blood were obtained at 0 (pre-suckling), 6, 12, 24, and 48 h of age, and blood chemistry, hematology, cortisol, and insulin were determined. Data were analyzed with fixed effects of late gestational nutritional plane (single data point) or nutritional plane, hour, and their interaction (data over time, repeated measures). Calving date was a fixed effect; calf sex was included when P < 0.25. We previously reported that late gestational nutritional plane did not affect gestation length or calf size at birth, but calving assistance and fetal malpresentation occurred more often in NR. Nutritional plane did not affect (P = 0.65) duration of parturition, but calves born to NR dams had slower times to attempt to stand (P = 0.09), slower times to stand (P = 0.02), and poorer 20 min vigor scores (P = 0.05). Serum immunoglobulin G and A concentrations at 48 h were greater (P ≤ 0.03) for NR calves. Rectal temperature of NR calves was less (P = 0.02) at 0 h, but greater (P = 0.04) at 24 h compared with CON. Circulating glucose, non-esterified fatty acids, triglycerides, cortisol, and insulin were not affected by nutritional plane (P ≥ 0.18). Total protein and globulin from 6 to 48 h were greater (P ≤ 0.02) in NR calves. Calves from NR dams had greater (P ≤ 0.08) gamma-glutamyl transferase at 6, 12, and 48 h. Serum aspartate aminotransferase was greater (P ≤ 0.07) from 0 to 24 h and creatine kinase was greater (P ≤ 0.04) from 6 to 24 h in NR calves. At 0 h, potassium was greater (P = 0.03) in NR calves. Calves born to CON had greater chloride (P = 0.08; main effect), sodium (P ≤ 0.09) from 0 to 48 h, and anion gap (P = 0.02) at 6 h. Hematocrit from 6 to 24 h and red blood cells and hemoglobin at 6 and 12 h were greater (P ≤ 0.09) in CON calves. These data indicate that nutrient restriction during late gestation resulted in less vigorous calves with more indicators of trauma in early life.

Evaluation of peripartum supplementation of methionine hydroxy analogue on beef cow-calf performance

The objective was to evaluate the effects of peripartum supplementation of a methionine hydroxy analogue (MHA) to primiparous, spring-calving beef females on dam and progeny performance. Angus heifers (n = 60) were blocked by expected parturition date, stratified by body weight (BW) and body condition score (BCS), and randomized to 1 of 15 pens. Pens were randomly assigned to 1 of 3 dietary treatments: a basal diet supplemented with 0 (M0), 15 (M15), or 30 (M30) g/animal/d of MHA (provided as MFP feed supplement, Novus International Inc., St. Charles, MO). Diets were fed from 45 ± 13 (SD) d pre-calving through 81 ± 13 d postpartum (DPP), after which all cow-calf pairs were managed as a single group on pasture until weaning (199 ± 13 DPP). Dam BW, BCS, and blood samples were taken at 6 predetermined timepoints. Progeny data were collected at birth, 2 intermediate timepoints, and at weaning. Milk samples were collected for composition analysis at 7 ± 2 DPP and at 55 ± 5 DPP. Serial progesterone samples were analyzed to establish resumption of cyclicity, and ultrasonography was performed at 55 ± 5 DPP to evaluate ovarian function. Cows were bred via artificial insemination at 82 ± 13 DPP and subsequently exposed to bulls for a 55-d breeding season. Pen was the experimental unit, and preplanned orthogonal contrasts were tested (linear effect and M0 vs. M15 + M30). Dam BW and BCS were not affected by treatment (P ≥ 0.29) throughout the study. Week 1 milk fat concentration increased linearly (P = 0.05) and total solids tended to increase linearly (P = 0.07) as MHA increased; however, no other milk components were affected (P ≥ 0.16). Treatment did not affect (P ≥ 0.16) dam reproductive parameters or progeny growth from birth until weaning. Post-calving, circulating methionine equivalents tended to linearly increase (P = 0.10) with increasing MHA supplementation. At breeding, plasma urea N linearly decreased (P = 0.03) with increased supplementation of MHA, and plasma non-esterified fatty acids were less (P = 0.04) in MHA-supplemented dams compared with dams receiving no MHA. Maternal circulating glucose, glutathione peroxidase, and thiobarbituric acid-reactive substances were not affected (P ≥ 0.15) by treatment at any point. These data indicate that peripartum supplementation of MHA may increase milk fat composition shortly after calving, but MHA supplementation did not improve progeny growth or dam reproductive performance in the current study.

Effects of nutrient restriction and subsequent realimentation in pregnant beef cows: Maternal endocrine profile, umbilical hemodynamics, and mammary gland development and hemodynamics

Our hypothesis was that maternal nutrient restriction would negatively impact the endocrine and metabolic status of the pregnant cow, therefore influencing the mammary gland in preparation for lactation. We further hypothesized that earlier timing of realimentation could prevent negative impacts of nutrient restriction. The objectives were to investigate the influence of nutrient restriction and realimentation during early to late gestation on endocrine profile, umbilical hemodynamics, and mammary gland development and hemodynamics in pregnant beef cows. In Experiment 1, on d 30 of pregnancy cows (initial BW = 667.5 ± 13.4 kg, BCS = 6.2 ± 0.1) were randomly assigned to one of 3 treatments: 1) 100% NRC requirements from d 30 to 254 of gestation (CCC; n = 6); 2) 60% NRC from d 30 to 85, thereafter being re-alimented to 100% NRC to d 254 (RCC; n = 5); 3) or receive 60% NRC from d 30 to 140, thereafter being re-alimented to 100% NRC to d 254 (RRC; n = 6). Cows were returned to a common outdoor facility for calving thereafter and were fed ad libitum. In Experiment 2, on d 30 of pregnancy, cows (initial BW = 620.5 ± 11.3 kg, BCS = 5.1 ± 0.1) were randomly assigned to dietary treatments including: control (CON; 100% NRC; n = 18) and nutrient restriction (RES; 60% NRC; n = 30). On d 85 of pregnancy, cows were either slaughtered (CON, n = 6 and RES, n = 6), remained on control (CC; n = 12) and restricted (RR; n = 12) treatments, or were realimented to control (RC; n = 11). On d 140 of pregnancy, cows were either slaughtered (CC, n = 6; RR, n = 6; RC, n = 5), remained on control (CCC, n = 6; RCC, n = 5), or were realimented to control (RRC, n = 6). On d 254 of pregnancy, all remaining cows were slaughtered (CCC, n = 6; RCC, n = 5; RRC, n = 6). Mammary hemodynamics and endocrine profile were measured. Serum urea nitrogen, NEFA, as well as fetal parameters were measured in Experiment 1; whereas in Experiment 2, mammary gland development was recorded. In Experiment 1, RRC cows had lower dry matter intake (P = 0.001) and consequently lower BW change (P = 0.06). However, maternal nutrition did not alter mammary hemodynamics, hormonal patterns, and fetal characteristics (P > 0.11). In Experiment 2, CCC cows had increased (P = 0.02) mammary gland blood flow ipsilateral to the gravid horn as well as greater (P = 0.02) mammary gland fat on d 254. Nevertheless, plane of nutrition did not alter hormonal concentrations nor mammary gland characteristics (P > 0.15). These data indicate that nutrient restriction did not alter mammary hemodynamics nor endocrine profile throughout gestation.

Frequency of maternal supplementation of energy and protein during late gestation modulates preweaning growth of their beef offspring

This study evaluated the effects of decreasing the frequency of dried distillers grains (DDG) supplementation during third trimester of gestation on cow physiology and offspring preweaning growth. At 201 ± 7 d prepartum (day 0 of the study), 120 Brangus crossbred cows were stratified by body weight (BW = 543 ± 53 kg) and body condition score (BCS = 5.47 ± 0.73), and then assigned randomly to 1 of 20 bahiagrass (Paspalum notatum) pastures (six cows and 4.7 ha/pasture). Treatments were randomly assigned to pastures (five pastures/treatment) and consisted of cows offered no DDG supplementation (NOSUP) or precalving supplementation of DDG dry matter at 1 kg/cow daily (7×), 2.33 kg/cow every Monday, Wednesday, and Friday (3×), or 7 kg/cow every Monday (1×) from day 0 to 77. All cows assigned to DDG supplementation received the same total amount of DDG dry matter (77 kg/cow) from day 0 to 77. All cow-calf pairs were managed similarly from day 77 until calf weaning (day 342). Supplementation frequency did not impact (P ≥ 0.16) any forage or cow reproduction data. Cow BCS on days 77, 140, and 342 did not differ among 1×, 3×, and 7× cows (P ≥ 0.29) but all supplemented cows, regardless of supplementation frequency, had greater BCS on days 77, 140, and 342 compared to NOSUP cows (P ≤ 0.04). Cows offered 1× supplementation had greater plasma concentrations of IGF-1 on days 35 and 140 compared to NOSUP, 3× and 7× cows (P ≤ 0.04), whereas 3× and 7× cows had greater plasma concentrations of IGF-1 on day 35 compared to NOSUP cows (P ≤ 0.005). Average plasma concentrations of glucose did not differ among 1×, 3×, and 7× cows (P ≥ 0.44), but all supplemented cows had greater plasma concentrations of glucose compared to NOSUP cows (P ≤ 0.05). Birth BW of the first offspring did not differ between 3× and 7× calves (P = 0.54) but both groups were heavier at birth compared to NOSUP calves (P ≤ 0.05). On day 342, calves born from 7× cows were the heaviest (P ≤ 0.05), whereas calves born from 1× and 3× cows had similar BW (P = 0.97) but both groups were heavier compared to calves born from NOSUP cows (P ≤ 0.05). In summary, decreasing the frequency of DDG supplementation, from daily to one or three times weekly, during third trimester of gestation of beef cows did not impact cow BCS but altered maternal plasma concentrations of IGF-1 and glucose, leading to reduced offspring preweaning growth.

Monensin supplementation during late gestation of beef cows alters maternal plasma concentrations of insulin-like growth factors 1 and 2 and enhances offspring preweaning growth

This study evaluated the effects of maternal prepartum supplementation of dried distillers grains (DDG), with or without monensin addition, on maternal performance and physiology and offspring preweaning growth. On day 0 (approximately 197 ± 4 d prepartum), 150 multiparous, Brangus crossbred beef cows were ranked by their initial body weight (BW; 524 ± 51 kg) and body condition score (BCS; 5.0 ± 0.63), and then randomly assigned into one of 15 bahiagrass (Paspalum notatum) pastures (10 cows and 8.1 ha/pasture). Maternal treatments were randomly assigned to pastures (5 pastures/treatment) and consisted of no prepartum supplementation of DDG (NOSUP) or supplementation of DDG at 1 kg/cow/d (dry matter basis; DM) added with 0 mg (SUP) or 200 mg/d of monensin (SUPMO) from days 0 to 77. Effects of maternal treatment and maternal treatment × day of the study were not detected (P ≥ 0.63) for any forage data. Cow BCS on day 35 and near calving (day 77) did not differ (P ≥ 0.19) between SUP and SUPMO cows but both groups had greater (P ≤ 0.001) BCS compared with NOSUP cows. Cow BCS at the start of the breeding season (day 142) and on day 168 were the greatest (P < 0.0001) for SUPMO cows, least for NOSUP cows, and intermediate (P ≤ 0.02) for SUP cows. Maternal plasma concentrations of glucose did not differ (P ≥ 0.25) among treatments. Plasma concentrations of insulin-like growth factor 1 (IGF-1) on day 77 were the least for NOSUP cows (P ≤ 0.05) and did not differ (P = 0.66) between SUP and SUPMO cows, whereas plasma concentrations of IGF-2 on days 35 and 77 were greatest (P ≤ 0.05) for SUPMO cows and did not differ (P ≥ 0.60) between NOSUP and SUP cows. Birth BW of first offspring did not differ (P = 0.77) between SUP and SUPMO calves but NOSUP calves were lighter at birth (P ≤ 0.05) compared with SUP and SUPMO calves. Percentage of cows pregnant with a second offspring did not differ (P = 0.72) between SUP and SUPMO cows and were the least for NOSUP cows (P ≤ 0.05). First offspring BW at weaning (day 325) was greatest (P ≤ 0.05) for SUPMO calves, least for NOSUP calves, and intermediate for SUP calves. Therefore, adding monensin into prepartum DDG supplements for Bos indicus-influenced beef cows did not increase cow prepartum BCS but led to greatest offspring preweaning growth, likely by modulating maternal plasma concentrations of IGF-1 and IGF-2 during gestation.

Effects of maternal winter vs. year-round supplementation of protein and energy on postnatal growth, immune function, and carcass characteristics of Bos indicus-influenced beef offspring

This 2-yr study evaluated the effects of winter vs. year-round supplementation of Bos indicus-influenced beef cows on cow reproductive performance and impact on their offspring. On day 0 of each year (approximately day 122 ± 23 of gestation), 82 to 84 mature Brangus cows/yr were stratified by body weight (BW; 475 ± 67 kg) and body condition score (BCS; 4.85 ± 0.73) and randomly assigned to 1 of 6 bahiagrass (Paspalum notatum) pastures (13 to 14 cows/pasture). Treatments were randomly assigned to pastures consisting of winter supplementation with molasses + urea (WMOL), or year-round supplementation with molasses + urea (YMOL) or wheat middling-based range cubes (YCUB). Total yearly supplement DM amount was 272 kg/cow and supplements were formulated to be isocaloric and isonitrogenous (75% TDN and 20% CP). On day 421 (weaning; approximately 260 ± 24 d of age), 33 to 35 steers/yr were vaccinated against parainfluenza-3 (PI3) and bovine viral diarrhea virus type 1 (BVDV-1) and transported 1,193 km to a feedlot. Steers were penned according to maternal pasture and managed similarly until slaughter. Data were analyzed using the MIXED and GLIMMIX procedures of SAS. On day 217 (start of breeding season), BCS was greater (P = 0.01) for YMOL than WMOL cows, whereas BCS of YCUB did not differ (P ≥ 0.11) to both WMOL and YMOL cows. The percentage of cows that calved, calving date, birth BW, and preweaning BW of the first offspring did not differ (P ≥ 0.22) among maternal treatments. Plasma cortisol concentrations were greater (P ≤ 0.001) for YCUB steers at feedlot arrival (day 422) than WMOL and YMOL steers. Moreover, YCUB steers had greater (P = 0.02) and tended (P = 0.08) to have greater plasma concentrations of haptoglobin compared to WMOL and YMOL steers, respectively. Antibody titers against PI3 and BVDV-1 viruses did not differ (P ≥ 0.25) among maternal treatments. Steer BW at feedlot exit was greater (P ≤ 0.05) for YMOL and WMOL than YCUB steers. However, feedlot DMI did not differ (P ≥ 0.37) by maternal treatment. Hot carcass weight, yield grade, LMA, and marbling did not differ (P ≥ 0.14) among maternal treatments. Percentage of steers that graded low choice was enhanced (P ≤ 0.05) for WMOL and YCUB than YMOL steers. Maternal year-round supplementation of range cubes or molasses + urea either did not impact or decrease growth, immune function, and carcass characteristics of the offspring when compared with maternal supplementation of molasses + urea during winter only.

Effects of replacement of corn silage and distillers' grain diets with hay during prepartum on the health and production performance of dairy heifers postpartum

In this study, we aimed to comprehensively evaluate the effects of prepartum replacement of corn silage and distillers' grain diets with hay on the postpartum health and production performance in dairy heifers. Pregnant Holstein dairy heifers were randomly assigned to two groups and fed different diets with the same net energy and protein concentrations. The low corn silage plus hay (CH) group diet mainly contained oat hay (28.5%), corn silage (25%) and folium ginkgo (23%). The high corn silage plus distillers' grains (CD) group diet contained corn silage (53.5%), distillers' grains (5%) and folium ginkgo (18%). Dairy heifers were fed from the beginning of pregnancy to the end of the transition period. Calf birthweight, postpartum morbidity, milk production and reproductive performance were determined. Compared with the cows in the CH group, those in the CD group presented increased calf birthweight and a high risk of some postpartum disorders (p < 0.05), particularly ketosis (37.63% vs. 24.54%) and retained placenta (9.41% vs. 3.92%). However, there was no difference between the groups in reproductive performance, including first timed artificial insemination (TAI) rate, date of TAI and conception rate of TAI. The lactation curves showed no difference in milk yield during the peak lactation period of primiparous cows between the CH and CD groups; the total milk production was 33.39 kg and 33.19 kg respectively. Notably, the time to peak milk production was delayed in the CD group. It can be concluded that replacing corn silage and distillers' grains with hay can reduce postpartum morbidity in dairy heifers and shorten the time to peak milk production.

Timing of maternal supplementation of dried distillers grains during late gestation influences postnatal growth, immunocompetence, and carcass characteristics of Bos indicus-influenced beef calves

This 2-yr study investigated the timing of dried distillers grains (DDG) supplementation during the third trimester of gestation of Bos indicus-influenced beef cows and its impact on their offspring performance. On day 0 of each year (84 d before calving), Brangus cows (n = 84/yr; cow age = 8 ± 3 yr) were stratified by initial body weight (BW; 482 ± 75 kg) and body condition score (BCS; 5.3 ± 0.8) and assigned randomly to one of six bahiagrass (Paspalum notatum) pastures (experimental units; 14 cows/pasture). Treatments were assigned randomly to pasture (2 pastures/treatment/yr) and consisted of no prepartum supplementation (CON), 2 kg/d of DDG from day 0 to 42 (LATE42), or 1 kg/d of DDG from day 0 to 84 (LATE84). Following calving (day 84), cow-calf pairs remained in their respective pastures, and cows were offered sugarcane molasses + urea (1.82 kg of dry matter/cow/d) from day 85 until the end of the breeding season (day 224). On day 347, steer calves (n = 38/yr; 11 to 15 steers/treatment/yr) were weaned and transported to the feedlot (1,193 km). Steers were penned according to cow prepartum pasture and managed similarly until the time of harvest. BCS at calving was greater (P < 0.01) for LATE42 and LATE84 vs. CON cows but did not differ (P = 0.16) between LATE42 and LATE84 cows. Calving date, calving percentage, and birth BW of the first offspring did not differ (P ≥ 0.22) among treatments. However, LATE42 cows calved their second offspring 8 d earlier (P = 0.04) compared with CON and LATE84 cows. At weaning (first offspring), LATE84 calves were the heaviest (P ≤ 0.05), CON calves were the lightest, and LATE42 calves had intermediate BW (P ≤ 0.05). Steer plasma concentrations of cortisol and haptoglobin and serum bovine viral diarrhea virus type-1 titers did not differ (P ≥ 0.21) between treatments. Steer serum parainfluenza-3 titers were greater (P = 0.03) for LATE42 vs. CON steers, tended to be greater (P = 0.10) for LATE84 compared with CON steers, and did not differ (P = 0.38) between LATE42 and LATE84 steers. Steer feedlot BW, average daily gain, dry matter intake, and hot carcass weight did not differ (P ≥ 0.36) between treatments. Marbling and the percentage of steers grading choice were greater (P ≤ 0.04) for LATE42 vs. CON steers, whereas LATE84 steers were intermediate. In summary, different timing of DDG supplementation during the third trimester of gestation could be explored to optimize cow BCS and offspring preweaning growth and carcass quality.

Improving Beef Progeny Performance Through Developmental Programming

Maternal nutritional management during gestation appears to modulate fetal development and imprint offspring postnatal health and performance, via altered organ and tissue development and tissue-specific epigenetics. This review highlighted the studies demonstrating how developmental programming could be explored by beef producers to enhance offspring performance (growth, immune function, and reproduction), including altering cow body condition score (BCS) during pregnancy and maternal supplementation of protein and energy, polyunsaturated fatty acids (PUFA), trace minerals, frequency of supplementation, specific amino acids, and vitamins. However, this review also highlighted that programming effects on offspring performance reported in the literature were highly variable and depended on level, duration, timing, and type of nutrient restriction during gestation. It is suggested that maternal BCS gain during gestation, rather than BCS per se, enhances offspring preweaning growth. Opportunities for boosting offspring productive responses through maternal supplementation of protein and energy were identified more consistently for pre- vs. post-weaning phases. Maternal supplementation of specific nutrients (i.e., PUFA, trace minerals, and methionine) demonstrated potential for improving offspring performance, health and carcass characteristics during immunological challenging scenarios. Despite the growing body of evidence in recent years, the complexity of investigating developmental programming in beef cattle production is also growing and potential reasons for current research challenges are highlighted herein. These challenges include: (1) intrinsic difficulty of accurately measuring cow milk production multiple times in cow-calf systems; (2) larger focus on Bos taurus vs. Bos indicus breeds despite the predominance of Bos indicus-influenced beef breeds in tropical/subtropical environments and their specific, and sometimes opposite, physiological and performance outcomes compared to Bos taurus breeds; (3) limited focus on interaction between prenatal and postnatal management; (4) sex-specific outcomes following similar maternal nutrition during gestation; (5) greater focus on nutrient deficiency vs. excess; (6) limited implementation of immunological challenges; and (7) lack of multigeneration and longer periods of offspring evaluation. This review provides multiple evidence that such obstacles need to be overcome in order to significantly advance the scientific knowledge of developmental programming in beef cattle and promote global beef production.

Interaction of CP levels in maternal and nursery diets, and its effect on performance, protein digestibility, and serum urea levels in piglets

Reduced protein levels in nursery diets have been associated with a lower risk of postweaning diarrhea, but the interaction with CP levels in maternal diet on the performance of the offspring remains unclear. The objective of this study was to determine the effect of protein content in sow gestation and piglet nursery diets on the performance of the piglets until slaughter. This was studied in a 2 × 2 factorial trial (35 sows, 209 piglets), with higher or lower (H or L) dietary CP in sow diets (168 vs 122 g CP/kg) during late gestation. A standard lactation feed was provided for all sows (160 g CP/kg). For both sow treatments, half of the litters received a higher or lower CP in the piglet nursery diet (210 vs 166 g CP/kg). This resulted in four possible treatment combinations: HH, HL, LH and LL, with sow treatment as first and piglet treatment as second letter. For each phase, all diets were iso-energetic and had a similar level of essential amino acids. P_s*p is the p-value for the interaction effect between sow and piglet treatment. In the nursery phase (3.5-9 weeks of age), a tendency toward interaction between piglet and sow treatments with feed efficiency (P_s*p = 0.08) was observed with HH having the highest gain:feed ratio (G:F) (0.74 ± 0.01), LH the lowest (0.70 ± 0.01) and the other two groups intermediate. In the growing-finishing phase, an interaction was observed between the piglet and sow diets with decreased G:F for LH (P_s*p = 0.04) and a tendency toward interaction with increased daily feed intake for LH (P_s*p = 0.07). The sow diet showed a tendency toward a long-lasting effect on the dressing percentage and meat thickness of the offspring, which was higher for the progeny of H sows (P_s < 0.01 and P_s = 0.02, respectively). At 23 weeks, serum urea concentrations tended to be lower for the HH and LL groups (P_s*p = 0.07). Fecal consistency scores were higher at day 10-day 14 after weaning for piglets from L sows (P_s = 0.03 and P_s < 0.01, respectively). At day 7 after weaning, fecal consistency score was higher for piglets fed the higher protein diet (P_p < 0.01). At 8 weeks of age, the apparent total tract digestibility of CP (ATTD_CP) interacted between piglet and sow diet (P_s*p = 0.02), with HH showing the highest digestibility values. In conclusion, the protein levels in sow late-gestation and piglet nursery diets interacted with feed efficiency, ATTD_CP and serum urea concentrations in the nursery phase.

Ante-Natal and Post-Natal Influences on Neonatal Immunity, Growth and Puberty of Calves-A Review

Simple Summary

The objective of this review is to give the reader an overview of interactions between immunity, growth and puberty in calves and highlight how these influence future performances. The risk of morbidity and mortality is high during the first four weeks of age. Adaption to extra-uterine life starts early during embryonic development and is underpinned by optimal maternal nutrition. It is known that colostrum is paramount to neonate nutrition and passive immunity. Good colostrum management allows the calf to develop coping mechanisms to efficiently utilize feed resources for optimal growth. A deeper understanding of these interactions paves the way for developing strategies to improve immune responses to environmental pathogens, optimal growth and timely attainment of puberty in calves. The literature reviewed here shows that there are opportunities to enhance future performance of cattle paying attention to the interaction of nutrition and immunity at early developmental stages. This then guarantees efficient neonate nutrition and profitable cattle production.

Abstract

Calf immunity, growth and puberty are important factors affecting heifer productivity. The first four weeks of age are critical for reducing calf morbidity and mortality. It is well documented that colostrum is paramount to neonatal nutrition and passive immunity, however, adaptation to extra-uterine life starts early during embryonic development. Therefore, successful calf rearing strategies are underpinned by adequate maternal nutrition during gestation, and good colostrum management. A deeper understanding of these interactions paves the way for developing strategies to improve immune responses to environmental pathogens, optimal growth and timely attainment of puberty in calves. The literature reviewed here shows that there are opportunities to enhance the future performance of cattle paying attention to the interaction of nutrition and immunity at each developmental stage. Therefore, the objective of this review is to give the reader an overview of interactions between immunity, growth and puberty in dairy calves and highlight how these influence future performances.

Maternal supplementation of energy and protein, but not methionine hydroxy analog, enhanced postnatal growth and response to vaccination in Bos indicus-influenced beef offspring

A 2-yr study evaluated the growth and postvaccination immune response of beef calves born from heifers offered no supplementation or pre- and postpartum supplementation of sugarcane molasses + urea with or without methionine hydroxy analog (MHA). On day 0 of each year (57 ± 5 d prepartum), Brangus crossbred beef heifers (n = 36/yr; 20 to 22 mo of age) were stratified by their initial body weight (BW; 396 ± 24.1 kg) and body condition score (BCS; 5.6 ± 0.43) and randomly allocated into 1 of 12 bahiagrass (Paspalum notatum) pastures (3 heifers/pasture). Treatments were randomly assigned to pastures (4 pastures/treatment/yr) and consisted of no supplementation (NOSUP) and supplementation of sugarcane molasses + urea (7.2 kg of DM/heifer/wk) with (MOL+) or without (MOL-) fortification with 105 g/heifer/wk of MHA. Treatments were provided from 57 ± 5 d prepartum until 17 ± 5 d postpartum (day 0 to 74). On day 74, all heifer-calf pairs were combined and managed as a single group until the end of the breeding season (day 237). Calves were early weaned at 89 ± 5 d of age (day 147), limit-fed at 3.5% of BW (DM basis) in drylot until day 201, and vaccinated against respiratory disease pathogens on days 160 and 188. Prepartum BCS on day 44 did not differ (P = 0.26) between MOL+ and MOL- heifers but both groups had greater (P < 0.0001) BCS than NOSUP heifers. Plasma concentrations of l-methionine on day 44 were the greatest (P ≤ 0.04) for MOL+ heifers and did not differ (P = 0.40) between NOSUP vs. MOL- heifers. Calf birth BW did not differ (P = 0.13) among treatments. Calf average daily gain (ADG) from birth to day 201 did not differ (P ≥ 0.17) between MOL+ vs. MOL- calves, but both groups had greater (P ≤ 0.05) ADG from birth to day 201 than NOSUP calves. Calf postvaccination plasma concentrations of glucose, cortisol, and haptoglobin did not differ among treatments (P ≥ 0.13). However, plasma concentrations of IGF-1 on day 167 and the overall positive vaccine seroconversion did not differ (P ≥ 0.18) between MOL- and MOL+ calves, but both were greater (P ≤ 0.04) compared with NOSUP calves. Hence, maternal supplementation of sugarcane molasses + urea increased BCS at calving and offspring BW gain and response to vaccination against respiratory pathogens compared with no maternal supplementation. MHA inclusion into maternal supplements effectively increased maternal plasma l-methionine concentrations but did not enhance maternal BCS at calving and offspring growth and postvaccination immune response.