Calf Growth Research Articles

Measurement of transfer of colostral passive immunity in dairy calves

Measurement of transfer of colostral passive immunity in dairy calves

Impact of cow milk production on cow-calf performance in the Nebraska Sandhills.

Livestock producers have tended to select for increased output traits like milk production and growth to increase productivity. Even with the increased selection for greater calf growth potential, some regions in the United States have seen a plateau in calf body weight (BW) at weaning (Lalman et al., 2019). When focusing on reaching maximum potential of these output traits, it is important to consider the multitude of variables that affect a production system. With increased milk production, nutrient requirements for cows become increased (Ferrell and Jenkins, 1984; Montano-Bermudez et al., 1990), which may not be met if range and forage availability for grazing is already limited at meeting lactation demands. Historically, weaning weight and milk production have been associated with a positive relationship with greater milk production resulting in heavier calves at weaning (Clutter and Nielsen, 1987; Abdelsamei et al., 2005). In contrast, others have only observed the benefit of increased milk production improving calf performance within the first 60 d after birth (Clutter and Nielsen, 1987; Ansotegui et al, 1991; Edwards et al., 2017). Gleddie and Berg (1968) reported the correlation between average daily gain (ADG) of calves and milk yield estimates increased between the first and second month and continued to decrease thereafter as the forage consumption increased. The reliance on milk for dietary energy can result in increased calf BW at peak lactation (Edwards et al., 2017), but benefits of increased milk production may decrease as stage of lactation increases. Our hypothesis was that increasing milk production would negatively affect cow reproductive performance while having no effect on calf performance. Therefore, the objective of this study was to determine the impact milk production has on subsequent cow reproductive performance and calf performance throughout the preweaning and postweaning phases.

PSXII-9 The effects of DFM plus tannins on measures of immunity and growth performance of weaned beef calves

Abstract A two-year study was conducted to determine the effects of direct-fed microbials plus tannins (DFM + TN) on weaned calf performance and indicators of innate immune response. Angus calves (n = 142 year 1; 143 year 2) were weaned at 6 months of age, transferred to a feedlot, and fed one of two diets for 42 days: a ration with added DFM + TN (2×108 Propionibacterium acidipropionici; 5×107 CFU/hd/day Lactobacillus animalis; 5×107 CFU/hd/day Bifidobacterium animalis; and tannins 15 g/hd/day) or a ration with no added DFM +TN (CON). Body weights were taken on consecutive days and averaged at the beginning and ending of the study, while single day weights were taken on d 14, and 28. Upon completion of the feeding study (year 2), calves (n = 72) were transported to Laramie, WY (204 km), where blood samples were taken on d 0, 2, 4, 7, and 9 relative to transportation to measure plasma haptoglobin. Data were compared among groups using a categorical response mixed model. The model included the fixed effect of treatment group and the data were measured repeatedly. DFM + TN calves had lower overall (P = 0.001) F:G and tended to have greater ADG (P = 0.15) and lower F:G (P = 0.12) during the first 28 days and greater overall ADG (P = 0.06) and greater (P = 0.11) total gain overall. There was a tendency (P = 0.09) for a treatment x day effect for DFM + TN calves to have lower plasma haptoglobin concentration on day 0 and 4 than CON calves. Weaned calves fed DFM + Tannins tended to have greater growth performance during the first 42 days post weaning and tended to have a reduction in plasma haptoglobin concentrations, suggesting a reduction in stress and a positive impact on calf growth.

51 Intranasal oxytocin improves plasma non-esterified fatty acids but not distance walked or cortisol concentrations at weaning

Abstract Beef calves express behaviors such as walking and vocalizing to a greater extend during weaning. These behaviors increase production costs due to compromised calf growth, health, and welfare. Oxytocin treatment reduces anxious behaviors and attenuates the HPA axis, thus the objective of this experiment was to evaluate the effects of oxytocin on calf growth, cortisol, and distance walked at weaning. A total of 20 Angus x Simmental heifer calves were randomly allotted to each treatment group (n = 10), intranasal oxytocin or saline (OXT, CON). All calves were administered the respective intranasal treatment at weaning (day 0), and then placed in the same pasture. Calves were weighed and blood sampled on days 0, 1, 7, and 14. Blood samples were used to quantify non-esterified fatty acids (NEFA), β-hydroxybutyrate, and cortisol. Each heifer was fitted with a global positioning system collar that recorded calf location every 10 seconds for 16 h on days 0, 7, and 14. To further evaluate calf behavior, observations were made on days 0, 7, and 14 using instantaneous scan sampling from 0730 to 0830, 1200 to 1300, and 1700 to 1800 h. Data were analyzed using a completely randomized design with repeated measures model (SAS 9.4). Providing calves with intranasal oxytocin on the day of weaning did not have an effect on the distance walked, observed behavior, body weight, β-hydroxybutyrate, or cortisol concentrations, however, there was a day effect (P < 0.05) for these variables. Intranasal oxytocin treatment did affect NEFA concentrations, as calves in the CON group had greater NEFA concentrations on day 1 compared with calves in the OXT group (P < 0.05). These data imply that intranasal oxytocin could have the capacity to decrease mobilization of NEFA, but this change was not enough to affect body weight 14 days after weaning.

203 Feeding a calf starter containing monensin alone or in combination with a blend of essential oils and a proprietary cobalt source to Holstein calves

Abstract Gut health is critical for neonatal calves, and nutritional technologies are needed for disease and stress prevention. Previous work feeding Monensin (MON) in combination with a blend of essential oils and a proprietary cobalt source (EOC) blend had demonstrated improved calf gut health and growth performance. The objective was to evaluate MON and EOC alone or in combination on calf growth performance. Eighty (80) new born Holstein calves were randomly assigned to one of four treatments arranged in a 2 x 2 factorial (MON and EOC). Treatments were: 1) Control without MON or EOC added to the calf starter (CS); 2) MON: 50.8 mg/kg CS (Norvikon Biotechnology Co., Hunan, China); 3) EOC: 44.1 mg/kg CS (Rum-A-Fresh, Ralco Inc. Marshall, MN); 4) MON+EOC: MON and EOC added to CS. Calves were fed colostrum followed by whole milk through weaning at 42 d, while CS was fed ad libitum through the 70-d experimental period. The MON by EOC interaction was found to be nonsignificant (P > 0.41) for growth performance. Calves fed without or with MON demonstrated similar (P > 0.70) body weight (BW; 68.7 and 68.9 kg without and with MON, respectively), while calves fed EOC demonstrated greater (P < 0.01) BW (67.3 and 70.4 kg without and with EOC, respectively) compared with calves fed without EOC. Calves fed a CS containing MON were similar (P > 0.47) in ADG (0.88 and 0.91 kg/d) compared with calves fed without MON; however, calves fed a CS with EOC increased (P < 0.01) ADG (0.84 and 0.95 kg/d) 13% through the 70 d experimental period compared with calves not fed EOC. These data demonstrate that EOC and MON fed in combination was not beneficial for enhancing growth performance, but that calf growth performance can be improved with EOC compared to MON.

PSIX-32 Assessment of Mucosa-associated Microbiota in the Colon and Rumen of Dairy Calves Fed High Plane of Milk and during Weaning Transition

Abstract The nature of weaning is considered as the most stressful period experienced by dairy calves and has been known to negatively affect calf growth and intake. The objectives of this study were to investigate the shift of rumen and colon mucosa-associated microbiota in dairy calves fed with a high plane of milk pre- and post-weaning, and whether such shifts are associated with rumen fermentation and growth performance. Six Holstein dairy bull calves were ruminally cannulated at the second week of life followed by weaning at the end of week 6. Ruminal and colon tissue samples were biopsied at the end of week 5, 7 and 12 to determine the bacterial community changes, and rumen content was collected at the same time to measure rumen fermentation parameters. QIIME2 was used to analyze microbial profiles and R studio software was used to determine the microbial changes and its relationship with phenotypic measures. Age-dependent profiles were observed for the colon mucosa associated microbiota but not for rumen mucosa associated microbiota, indicating that varied responses to weaning transition exists between colon and rumen mucosa associated microbiota. As calves aged, higher abundance of taxa such as Delftia (associated with hexadecanoic acid production) and lower abundance of Veillonella (associated with short-chain organic acids utilization) were detected in the colon mucosa. The rumen also displayed taxonomic changes with decreases in Pseudobutyrivibrio in older calves. In addition, we identified significantly positive correlations between Prevotella associated with rumen mucosa and average daily gain, Isovalerate and Isobutyrate, suggesting that this genus may promote rumen fermentation during weaning transition. Our findings suggest that weaning transition affects rumen and colon mucosa-associated bacteria, and some of the rumen mucosa-associated microbiota promote rumen fermentation during this period, which may have long-term effects on animal health and productivity.

202 Dietary supplementation with a blend of essential oils and a proprietary cobalt source along monensin may be antagonistic to growth performance of Holstein yearling bulls

Abstract Our previous work has indicated that feeding a blend of essential oils and a proprietary cobalt source (EOC) in combination with monensin (MON) may not be mutually beneficial to dairy calf growth performance. To evaluate this observation further, a 240 d long-term growth experiment was conducted using 12 young growing Holstein bulls using a 2 × 2 factorial treatment arrangement. Main factors were EOC (Rum-A-Fresh, Ralco, Inc., Marshall, MN) and monensin (MON; Norvikon Biotechnology Co., Hunan, China) arranged in 4 treatments: 1) Control: ration fed without EOC or MON; 2) EOC: EOC fed at 26 mg/kg DM; 3) MON: MON fed at 25 mg/kg DM; and 4) EOC+MON: EOC and MON fed in combination. Holstein bulls were 70 d of age and similar in BW (93.3 ± 4.54 kg) and individually fed for 280 d. Body weights, frame measurements, and blood samples were collected monthly. Interactions of EOC by MON were detected for BW, BW gain, ADG, and a trend for feed conversion. Bulls fed EOC or MON demonstrated greater final BW (367.7, 385.2, 381.2, and 357.5 kg for Control, EOC, MON, and EOC+MON, respectively), while BW gains (277.2, 291.5, 284.8, and 265.2 kg) and ADG (1.16, 1.22, 1.19, 1.11 kg/d) were greatest for bulls fed EOC or MON compared with bulls fed EOC+MON, with bulls fed Control being intermediate and similar to bulls fed MON. Intake of DM was greater for bulls fed EOC (6.55, 6.99, 6.60, and 6.42 kg/d) compared with bulls fed remaining treatments. Feeding EOC or MON separately can improve growth performance of growing Holstein bulls. Why the combination of EOC and MON is antagonistic to growth performance of Holstein bulls is unknown.

PSIII-8 Impact of SYNOVEX® ONE GRASS implantation during suckling on pre-weaning calf growth performance

Abstract Historic data supports the use of pre-weaning implants to maximize beef calf weaning weight, but their use has declined over the recent decade. A total of 96 beef steers (initially 85.2 kg BW and > 45 d of age) were used in a 168-d study to evaluate the effects of Synovex C® implantation during suckling on pre-weaning calf growth performance. At initial processing, calves were individually weighed and allotted in a completely randomized design to one of two treatments: 1) not implanted (control) or 2) implanted with 150 mg of trenbolone acetate and 21 mg of estradiol benzoate (SYNOVEX® ONE GRASS, Zoetis, Kalamazoo, MI). All calves were weighed on d 0 (implantation), 83, 126 and 168 (weaning), with ADG calculated for each period. Data were analyzed using the GLIMMIX procedure of SAS (v9.4, Cary, NC). There were 48 replicates per treatment, with grazing location as a random effect. While there were no detected differences in BW during the initial phases (P > 0.10), implanted calves tended to have greater (P = 0.100) greater weaning weight than non-implanted calves (279 vs. 265 kg, respectively). Calves implanted with SYNOVEX® ONE GRASS had 0.8, 0.12, and 0.16 kg/d greater (P < 0.05) ADG than those that were not implanted in all three phases. This resulted in an average of 0.10 kg/d greater (P = 0.002) ADG in implanted calves overall compared to the control. In conclusion, this research showed significant increases in suckling calf ADG in implanted calves compared to their non-implanted counterparts, which led to a tendency for 14-kg greater weaning weights. Additional research is warranted to consider the post-weaning growth and impact of re-implanting, but this data reinforces previous literature that suckling calf implantation continues to be cost effective for cow-calf producers.

108 Influence of Cow Body Weight Changes on Calf Growth during the Summer Grazing Period

Abstract In spring calving beef herds, the summer grazing period allows the mature cow to recuperate prior to the next calving season. Cow body weight changes during the summer can vary from minimal to extreme, which may also alter calf growth rates. The objective of this study was to determine the influence of cow body weight changes on calf growth during the summer grazing season. Cows and calves were weighed at the beginning, mid-point and end of the summer grazing season with the end-point being weaning. Based on these weights, cows were categorized into one of four groups: low (LO), medium (MED), high (HI), and extreme (EXT). Groups were determined based on the percent body weight gained across the season with LO being less than 4.99%; 5–9.99% as MED; 10–14.99% as HI, and above 15% as EXT. Data were collected over a 3-yr period utilizing a total of 52 mature Angus cows and 102 Angus calves. Cows were rotationally grazed on mixed grass pastures containing tall fescue and supplemented with corn silage for part of the grazing season. Cows were managed in two groups, but all pastures were grazed by all cows during the season. Calves were provided ad libitum access to creep feed for the entire grazing season. All calves were treated similarly and bulls were left intact until weaning. Data were analyzed in the MIXED procedure of SAS with year and group effects with age of dam as a covariate. Calves had the lowest early ADG in LO cows compared to all other groups (P = 0.01). Overall calf ADG tended to be different between groups as LO cows had slower growing calves compared to EXT or HI dams (P = 0.09). Generally, cows that gained the least amount of weight over the grazing season had slower growing calves.

126 Pre- and post-partum supplementation of molasses/urea, with or without methionine fortification, to enhance growth and physiology of Bos indicus-influenced primiparous cows and their offspring

Abstract A 2-yr study evaluated the effects of molasses/urea supplementation during pre- and early postpartum, with or without methionine fortification, on growth and physiology of primiparous cows and their offspring. On d 0 of each yr, 36 cows were stratified by BW and BCS (396 ± 54 kg; 5.67 ± 0.66) and randomly assigned to 1 of 12 bahiagrass pastures (3 cows and 1.2 ha/pasture). Treatments were randomly assigned to pastures (4 pastures/treatment) and consisted of no supplementation (NOSUP), 1 kg/d of molasses/urea (MOL; DM basis), or 1 kg/d of MOL + 18 g/d of methionine hydroxy analog (MOLMET; Alimet, Novus, St. Charles, MO). Supplementation began 56 d before parturition (d 0) and ended when all cows within each pasture had calved (d 74). Calves were early weaned on d 147. On d 154, 24 calves (8 calves/treatment) were transferred to individual drylot pens, and offered ad libitum stargrass hay plus soybean hulls-based concentrate DM (75% TDN; 22% CP) at 3% of BW for 47 d. On d 160, calves were vaccinated against bovine viral diarrhea virus-1 (BVDV-1) and parainfluenza-3 (PI-3). Data were analyzed using the MIXED procedures of SAS. Cow BCS at calving was greater (P ≤ 0.05) for MOL and MOLMET vs. NOSUP but the overall percentage of pregnant cows did not differ among treatments (P = 0.82). Calf ADG from birth to drylot exit did not differ (P = 0.83) between MOL and MOLMET but was least (P ≤ 0.04) for NOSUPP calves. Seroconversion to BVDV-1 and PI-3 viruses were greater (P ≤ 0.05) for MOL and MOLMET vs. NOSUP calves. Hence, cow supplementation of molasses/urea during pre- and early postpartum improved cow prepartum BCS, and calf growth and humoral immunity. Methionine fortification of supplements did not impact cow and calf performance.

38 Effect of Breed on Dairy Calf Vigor from Birth to Preweaning

Abstract There is a stigma in the dairy industry that Brown Swiss calves are not as quick to stand and nurse following birth compared to other dairy breeds. The objective of this study is to determine if Brown Swiss calves are less vigorous at birth and if this affects their health status and early calf growth compared with the dairy industry’s most prominent breed, the Holstein. All calves (n = 25) were scored shortly after birth using a modified Apgar scoring system used for infants. Thirteen parameters divided into 5 categories were evaluated to determine overall vigor of each calf. These included visual scores for meconium staining and swelling of the head; initial mobility scores for time to lift head, time to stand, and ear position; general responsiveness scores included strength of the suckling reflex, head shake in response to straw in nasal cavity, tongue withdrawal when pinched, and eye reflex; oxygenation score for mucus membrane color; rates scores included heart rate, respiration rate, and temperature. In addition to the vigor scoring, a weight was taken at birth and 2 weeks post calving. Jugular blood samples were collected at birth, 24 hours later, and at 2 weeks of age, and serum was stored for later analysis of haptoglobin and IgG concentration. Vigor scores and weight data were analyzed by breed using the mixed procedure in SAS. The vigor score for suckling reflex was lower (P = 0.04) for Brown Swiss calves (1.69, n = 12) than Holstein calves (2.39, n = 13). A weakened suckling reflex can lead to more challenges when consuming colostrum. Early colostrum intake is vital to obtaining passive immunity and maintaining health status in young calves. All other vigor scores collected for the Brown Swiss and Holstein calves did not differ (P > 0.05).

39 Effect of Breed on Dairy Calf Vigor from Birth to Preweaning

Abstract There is a stigma in the dairy industry that Brown Swiss calves are not as quick to stand and nurse following birth compared to other dairy breeds. The objective of this study is to determine if Brown Swiss calves are less vigorous at birth, and does this impact their health status and early calf growth compared with the dairy industry’s most prominent breed, the Holstein. All calves (n = 25) were scored shortly after birth using a modified Apgar scoring system used for infants. Thirteen parameters divided into 5 categories were evaluated to determine overall vigor of each calf, these included visual scores for meconium staining and swelling of the head; initial mobility scores for time to lift head, time to stand, and ear position; general responsiveness scores included strength of the suckling reflex, head shake in response to straw in nasal cavity, tongue withdrawal when pinched, and eye reflex; oxygenation score for mucus membrane color; rates scores included heart rate, respiration rate, and temperature. In addition to the vigor scoring a weight was taken at birth and 2 weeks post calving. Jugular blood samples were collected at birth, 24 hours later, and at 2 weeks of age and serum was stored for later analysis of haptoglobin and IgG concentration. Vigor scores and weight data were analyzed by breed using the mixed procedure in SAS. The vigor score for suckling reflex was lower (P = 0.04) for Brown Swiss calves (1.69, n = 12) than Holstein calves (2.39, n = 13). A weakened suckling reflex can lead to more challenges when consuming colostrum. Early colostrum intake is vital to obtaining passive immunity and maintaining health status in young calves. All other vigor scores collected for the Brown Swiss and Holstein calves did not differ (P > 0.05).

Calf growth and reproductive performance of cows in the farm practicing the year-round grazing system for cows with their calves in the northern Tohoku region

Calf growth and reproductive performance of cows in the farm practicing the year-round grazing system for cows with their calves in the northern Tohoku region

Effects of management system on beef heifer growth and reproductive performance

This study evaluated the effect of heifer development system on body weight (BW), body condition score (BCS), fescue toxicosis symptoms, reproductive performance, and subsequent calf growth of fall-calving beef heifers. Angus × Simmental heifers [n = 399; 240 ± 20.0 kg initial BW; age = 252 ± 20 d] were stratified by BW and BCS and assigned to 1 of 12 groups in each of the two production years. The study utilized a stratified randomized design. Pens were randomly assigned to four treatments: drylot (DL) development (fed ad-libitum diet consisting of 90% hay and 10% DDGS on a dry matter basis), grazing endophyte-infected fescue supplemented daily (2.3 kg as-fed/heifer/d; 50:50 mix of soybean hulls and DDGS; E+/S), grazing endophyte-infected fescue and supplemented from the midpoint of treatment period until breeding (4.5 kg as-fed/heifer/d; 50:50 mix of soybean hulls and DDGS; E+/LS), and grazing novel endophyte-infected fescue with no supplement (NE+/NS). Treatments ceased on d 168 [time of artificial insemination (AI)] and heifers were commingled and managed as a group through second breeding season. Heifers in DL had greatest (P ≤ 0.05) BW and BCS from d 28 until d 254. Furthermore, E+/S heifers had greater (P ≤ 0.05) BW and BCS than both E+/LS and NE+/NS from d 28 until d 168. On d 56 and 84, E+/LS heifers had lower (P ≤ 0.05) BW and BCS compared to NE+/NS, but on d 148 treatments reranked and E+/LS remained at a greater (P ≤ 0.05) BW and BCS compared to NE+/NS through the first breeding season. Drylot heifers had greatest (P ≤ 0.05) percentage cycling and percentage of mature BW at AI (66.6%) and had greater (P ≤ 0.05) AI and overall pregnancy rates compared to E+/LS and NE+/NS. The E+/S (55%) and E+/LS (53.7%) heifers were developed to a greater (P < 0.01) percentage of mature BW than NE+/NS (49.3%). A greater (P ≤ 0.02) percentage of DL and E+/S heifers were pregnant at the end of the first breeding season (89.3 and 85.1%; respectively) compared to NE+/NS (61.5%). In summary, DL heifers had the greatest BW and BCS at AI, percentage cycling, and AI pregnancy rate. However, this strategy did not result in differing overall pregnancy rates between DL, E+/S, and E+/LS and there were no differences in milk production, rebreeding reproductive performance, and calf performance between all treatments. Finally, the poorest AI and overall pregnancy rates of the NE+/NS heifers suggests this is not a viable development strategy for fall-born heifers.

The effects of manual and automated milk feeding methods on group-housed calf health, behaviour, growth and labour

It has been suggested that the integration of automatic feeding systems into calf rearing programmes has the potential to improve calf behaviour, growth and the associated labour. Thus, the objective of this study was to compare the effects of automatic and manual feeding systems on calf health, behaviour, growth and labour. A population of 60 dairy heifer calves was used: 44 Holstein-Friesian (HF) and 16 HF x Jersey (JE), balanced for birth weight (33 ± 4.1 kg), birth date (26 January ± 3.2 days) and breed. The experiment was a randomised block design including two treatments; i) automated calf feeding system (AFS) and ii) manual calf feeding system (MFS). Each treatment was replicated once, so a total of four balanced groups of 15 heifer calves were created. Milk replacer was offered at a rate of 6 L per calf/day (reconstitution rate 15%), with fresh water, ad-libitum concentrates and hay offered from three days old. Calves were weaned based on weight (90 kg for HF and 85 kg for HF x JE). Total labour input/day was consistently less for AFS compared to MFS (-00:01:06 per calf/day). Automatic feeding systems had a higher labour requirement for health inspections and training to the system (+00:00:15 per calf/day and +00:02:06 per calf/day, respectively), on a per calf basis, compared to MFS. The MFS-calves had an increased likelihood of experiencing faecal scores > 0 (Odds Ratio (OR) = 2.009; Confidence Interval (CI) = 1.463 – 2.759). The MFS-calves were also more likely to defecate and urinate (OR= 1.450; CI = 1.080-1.945), eat (OR= 1.281; CI = 1.140 – 1.439) and socially interact (OR= 1.300; CI = 1.111 – 1.521), compared to standing. There was no difference in number of days from birth to weaning (80.8 days) and weight at weaning (92.9 kg); average daily gain in both the pre (81 days) and post weaning (79 days) periods was similar between the two treatments (0.74 and 0.70 kg/day, respectively). Patterns for behaviours such as lying and playing were similar and low levels of abnormal behaviours were found in both treatments. Calves in both treatments exhibited good health and normal behavioural patterns as well as similar growth rates. Thus, when managed appropriately, the saving of labour is a distinct advantage automated feeding systems have over their manual counterparts when rearing group-housed calves.

Effect of crude protein level in high grain diets on calf growth and feed utilization

This study assessed the effect of crude protein level in the diet on animal performance, feed conversion ratio and N utilization, in early-weaned lot-fed calves. Four iso-energetic rations were formulated (ME: 12.0 MJ/kg dm) differing in the crude protein content (CP: 12%, 15%, 17% and 21%, DM basis), and offered in a random experimental design to 24 Hereford calves (107.2 ± 21.5 kg). Animals were individually housed and fed ad libitum twice a day for 84 days. Increasing CP levels in the diet promoted a quadratic response (P&lt;0.01) for dry matter intake (kg/d) and liveweight gain (LWG, kg/d), with maximum LWG of 1.36 kg/d for CP= 17.5%, without differences in subcutaneous back fat thickness (3.70 ± 0.73 mm, P = 0.25) or feed conversion ratio (4.44 ± 0.26, P&gt; 0.10). As CP increased in the diet, N consumption increased quadratically (P &lt;0.01), and an improvement was observed for CP (P = 0.053) and ndf (P = 0.020) apparent digestibility. Daily excretion of N in feces tended to decrease (P = 0.06), while urea-N concentration both in blood (P = 0.013) and urine (P = 0.046) increased. These results show that a level of 17% CP in the diet would optimize the performance of lot-fed early-weaned beef calves while controlling the excretion of N to the environment.

MRNA expression of myogenic-adipogenic makers and adipocyte in skeletal muscle of Hanwoo calves at newborn and 6 months of age.

This study was conducted to compare the mRNA expression levels of myogenic-adipogenic makers in the skeletal muscle and adipocytes formation, body weight, rumen weight, and papilla length on Hanwoo calves at newborn and 6 months of age. Animals used three newborn Hanwoo calves (NC) and three Hanwoo calves 6 months of age (SC). Body weight and rumen weight were significantly increased in SC compared to NC (p < 0.01), and papilla length was longer about 10-fold in SC than NC. Adipocytes was possible to visually identify more adipocytes in SC compared to NC, and were mainly formed around the blood vessels. mRNA expression of myogenin, myosin heavy chain 1 and myosin heavy chain 2A in both longissimus dorsi (LD) and semimembranosus (SM) was found to increase with calves growth (p < 0.01), and it was confirmed that have higher levels of mRNA expression in SM than LD. In LD tissues, the mRNA expression of stearoyl-CoA desaturase (SCD, p < 0.03) and peroxisome proliferator activated receptor γ (PPARγ, p < 0.04) was significantly higher in SC than NC. In SM tissues, mRNA expression levels of SCD (p < 0.02) and CCAAT/enhancer binding protein β (C/EBPβ, p < 0.01) were higher in SC than NC, and also mRNA expression levels of PPARγ increased, but there was no significant difference. Thus, the calves period suggests that it is an important step in the development of the rumen and the myogenesis and adipogenesis.

Administering an Appeasing Substance to Gir × Holstein Female Dairy Calves on Pre-Weaning Performance and Disease Incidence.

Simple SummaryStress is a common issue faced by ruminants throughout their productive lives, with significant effects on health and performance of the herd. Hence, strategies that alleviate stress-induced responses with a concomitant increase in performance and health are warranted. Administration of the bovine appeasing substance improved performance and reduced the costs related to pharmacological intervention of pre-weaning dairy calves. Therefore, the utilization of the bovine appeasing substance is a feasible alternative to improve health and performance of the dairy cattle herd.(1) Background: Ruminants often face stressful situations throughout their productive lives. More specifically, pre-weaning dairy calves are exposed to novel environments, feedstuffs, and pathogens that affect their health and performance. Hence, alternatives that reduce stress and promote growth of pre-weaning dairy calves are warranted. Therefore, this study evaluated the effects of biweekly bovine appeasing substance (BAS) administration on performance and disease incidence in dairy Gir × Holstein female calves prior to weaning. (2) Methods: At birth, 140 female Gir × Holstein calves were randomly assigned to receive BAS (SecureCattle; (IRSEA Group, Quartier Salignan, France; n = 70) or placebo (BAS carrier, diethylene glycol monoethyl ether; CON; n = 70) biweekly until weaning (70 days of age). Calves were allocated into individual housing at random, with no physical contact between treatments to avoid cross-contamination. Experimental treatments (5 mL) were applied topically to the nuchal skin area of each calf. Throughout the experimental period, all animals were observed daily for medical conditions (diarrhea, pneumonia, and others), medical/pharmacological interventions were recorded, and the costs related to these procedures were analyzed. Concurrently with treatment application, calves were individually weighed, and data were analyzed using animal as the experimental unit. (3) Results: Treatment × day and treatment × period (14-day interval) interactions were observed for body weight (BW) and average daily gain (ADG; p ≤ 0.05), respectively. Calves receiving BAS had greater BW at weaning (p = 0.02) and tended to have a greater BW on day 56 (p = 0.06). Similarly, ADG was greater for BAS from days 42 to 56 (p = 0.04) and tended to be greater from days 56 to weaning (p = 0.10). No differences were observed on the overall occurrence of diseases (p = 0.92), whereas the most common observed diseases were diarrhea and pneumonia. The incidence and mean age at which animals were detected with these diseases did not differ (p ≥ 0.46). Nonetheless, CON calves detected with disease had a reduced ADG vs. BAS-administered counterparts (p < 0.01). No differences were observed between disease-diagnosed BAS vs. healthy CON, but healthy BAS had a greater ADG vs. healthy CON (p = 0.03). A treatment effect was observed for the cost per head of each pharmacological intervention (p = 0.05). (4) Conclusions: In summary, BAS administration at a 14-day interval improved performance and reduced the costs of pharmacological interventions of pre-weaning Gir × Holstein dairy calves.

Grain Yield and Beef Cow–Calf Growth Performance in Dual-Purpose and Conventional Grain Wheat Production Systems and Stockpiled Tall Fescue Pasturing

Dualpurpose wheat (Triticum aestivum L) can be used for cattle grazing while producing grain from the same crop. In a two-year study, wheat forage production, grain yield, and growth performance of beef cow–calf pairs grazed on wheat pasture for 2–3 weeks in spring was compared with the conventional wheat grain production system and stockpiled tall fescue (Festuca arundinacea (L.) Schreb) pasturing. Grazing wheat resulted in grain yield (4.1 vs. 4.6 t ha−1) and test weight (65.9 vs. 66.7 kg hL−1) similar to the conventional grain production system. Wheat accumulated significantly lower forage dry matter yield (0.9 vs. 1.9 t ha−1) in spring with higher crude protein (190.2–290.2 vs. 122.0–151.0 g kg−1) and low fiber contents compared to the stockpiled tall fescue pasture. Wheat pasture presented risk for the development of grass tetany with regard to N, K, Na, and Mg contents. Calves grazed on wheat gained 1143–1370 gd−1 body weight compared to the 826–879 gd−1 in the stockpiled tall fescue pasturing. Cows had inconsistent and mixed body weight change response. With warmer temperatures and adequate precipitation controlled grazing of wheat in spring by beef cow–calves offered weight gain benefits exceeding the stockpiled tall fescue pasturing and grain production similar to the conventional wheat grain system.

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.