Provision of beta‐glucan prebiotics (cellooligosaccharides and kraft pulp) to calves from pre‐ to post‐weaning period on pasture

We conducted two feeding experiments to evaluate the effects of supplementation with either cellooligosaccharide or kraft pulp on growth performance in grazing beef calves (Japanese Black) from 4 weeks pre‐weaning to 12 to 16 weeks post‐weaning. In Experiment 1 (20‐week duration), nine calves (2.9‐month‐old females) were assigned to either a control group (CON) or an experimental group (CEL) fed cellooligosaccharide at a rate of 10 g/day mixed with concentrate. Average daily weight gain tended to be greater in CEL than in CON, especially after 1 month of weaning. In Experiment 2 (16‐week duration), 10 calves (2.0‐month‐old females) were assigned to either a control group or an experimental group (KRA) fed kraft pulp at a rate of 10% replacement of total digestible nutrients with concentrate. The proportion of fibrolytic bacteria increased and that of methanogenic Archaea decreased in the rumen microbial community composition of KRA calves in Experiment 2, whereas the decrease in Fibrobacter and Archaea was observed in CEL calves at first 4 weeks in Experiment 1. We conclude that beta‐glucan prebiotic supplementation to grazing calves at pre‐weaning would affect rumen microbial composition and modified rumen fermentation characteristics, leading to a better rumen environment via different means.     

The effect of different combinations of local anaesthesia,sedative and non-steroidal anti-inflammatory drugs on daily growth rates of dairy calves after disbudding

AIM: To assess the effect of sedation and local anaesthesia (LA) at disbudding, and the addition of meloxicam or ketoprofen treatment, on weight gain in dairy calves following disbudding.

METHODS: Friesian-Jersey cross calves, from four dairy farms, were enrolled when 3–6 weeks old. All calves (n=271) were disbudded by veterinary personnel and randomly assigned to six groups: 136 were disbudded without sedation or LA, of which 31 received 20 mg meloxicam S/C and 75 received 150 mg ketoprofen I/M. A further 135 were disbudded with sedation (0.25 mg/kg xylazine I/M) and LA, of which 30 also received meloxicam and 75 received ketoprofen. Calves were weighed 3 days before, and 15 and 30 days after, disbudding (Day 0). Daily weight gain was analysed using mixed models and ANOVA.

RESULTS: Complete results were obtained from 263 calves. From Day ?3 to Day 15, the growth rate of calves disbudded without pain relief (0.53 (95% CI=0.47–0.60) kg/day) was less that of calves disbudded with some form of pain relief (0.65 (95% CI=0.62–0.68) kg/d; p=0.004). There was no difference between the effect of meloxicam or ketoprofen (p=1.00). An interaction between use of sedation and LA and additional non-steroidal anti-inflammatory drugs (NSAID) meant that NSAID treatment did not increase growth rates in calves disbudded with sedation and LA but did increase growth rates for calves disbudded without pain relief (p<0.05). From Day 16 to Day 30 there was no effect of NSAID treatment on growth rate, but calves receiving LA and sedation grew faster (0.74 (95% CI=0.69–0.80) kg/day) than calves disbudded without LA and sedation (0.66 (95% CI=0.61–0.71) kg/day; p=0.018). From Day ?3 to Day 30, calves disbudded with sedation and LA grew faster (0.71 (95%CI=0.64–0.77) kg/day) than calves disbudded without sedation and LA (0.60 (95% CI=0.55–0.65) kg/day; p=0.011). However, addition of NSAID to sedation and LA made no further difference to growth rates (p=0.69).

CONCLUSIONS: Dairy calves disbudded with no pain relief had slower growth rates than calves receiving pain relief. From Day 15 to 30 calves given no pain relief, or NSAID alone, grew more slowly than those receiving sedation and LA at disbudding. The addition of NSAID treatment to sedation and LA did not further increase growth rates.

CLINICAL RELEVANCE: This study adds to the evidence that pain management when disbudding is beneficial for calf productivity as well as calf welfare.     

A hematologic and blood chemical study of Swedish purchased calves.

The hemoglobin (Hb), packed cell volume (PCV), erythrocytes (R.G.), serum iron (SI) and unsaturated iron binding capacity (UIBG) were examined in a total of 386 purchased calves for the duration of 1 year. The calves were tested within 3 days of arrival at the buyer’s herd. The average age of the calves was 28 ± 10 days ().The results may be summarized as follows:

1. Approx. 35% of the calves had Hb values ≦ 10.0 g/100 ml.
2. Fifteen% of the calves had ≦ 6.0 × 10⁶ R.C. per µl.
3. Fifty-three calves or about 14% showed SI values ≦ 40 µg/100 ml and 131 calves or 34% ≦ 80 µg/100 ml.
4. Twenty-seven % of the calves had UIBG values > 501 µg/100 ml.
5. Almost half the calves (48%) had a saturation percentage of transferrin with iron below 20% and 138 calves (36%) below 15%.

These figures among others in the study indicate that 13–35% of the purchased calves suffered from iron deficiency anemia.     

Leucine‐induced promotion of post‐absorptive EAA utilization and hepatic gluconeogenesis contributes to protein synthesis in skeletal muscle of dairy calves

The high rate of protein synthesis in skeletal muscle of dairy calves can benefit their first lactation even lifetime milk yield. Since the rate of protein synthesis is relatively low in the post‐absorptive state, the aim of this research was to determine whether leucine supplementation could increase the post‐absorptive essential amino acid (EAA) utilization and protein synthesis in the skeletal muscle. Ten male neonatal dairy calves (38 ± 3 kg) were randomly assigned to either the control (CON, no leucine supplementation, n = 5) or supplementation with 1.435 g leucine/L milk (LEU, n = 5). Results showed that leucine significantly increased the length and protein concentration in longissimus dorsi (LD) muscle, whereas it decreased creatinine concentration and glutamic‐oxalacetic transaminase (GOT) activity. Compared to the control group, leucine supplementation also reduced the glutamic‐pyruvic transaminase (GPT) activity. Supplementation of leucine improved the phosphorylation of mammalian target of rapamycin (mTOR), eukaryotic initiation factor 4E‐binding protein 1 (4EBP1) and substrates ribosomal protein S6 kinase 1 (p70S6K). Supplementation of leucine resulted in increased concentrations of glucose, methionine, threonine, histidine and EAAs and decreased concentration of arginine in serum. Liver glucose concentration was higher and pyranic acid was lower in LEU compared to CON. In conclusion, leucine supplementation can promote post‐absorptive EAA utilization and hepatic gluconeogenesis, which contributes to protein synthesis in skeletal muscle of dairy calves.     

Rumen degradation characteristics of sweet potato foliage and performance by local and crossbred calves fed milk and foliage from three cultivars

The study investigated rumen dry matter (DM) degradability characteristics in a completely randomized design and the effects of milk, sweet potato foliage (SPF) from three cultivars (A = TIS-87/0087; B = TIS-8164; C = TIS-2532.OP.1.13), dried brewers' grains (DBG) and cottonseed meal (CSM) as supplements to Panicum maximum (Panicum) for pre-weaned calves in randomized complete block designs. Diet 1 = milk + SPF-A foliage + Panicum, Diet 2 = milk + SPF-B foliage + Panicum, Diet 3 = milk + SPF-C foliage + Panicum, and Diet 4 = milk + DBG & CSM + Panicum (as control). Dry matter (130 ± 0.4 to 864 ± 3.9 g kg^− 1), ash (54 ± 4.2 to 173 ± 2.8 g kg^− 1 DM), OM (827 ± 4.2 to 946 ± 5.7 g kg^− 1 DM), N (7.4 ± 0.6 to 38.6 ± 1.4 g kg^− 1 DM), and NDF (439 ± 1.4 to 774 ± 8.5 g kg^− 1 DM) contents were highly significant (P < 0.01). In Trial I, 16 pre-weaned calves were used over 70 d with milk intake (34.8 ± 4.4 ml kg W^− 0.75 d^− 1), Panicum DMI (22.3 ± 2.77 g kg W^− 0.75 d^− 1), total DMI (35.7 ± 2.83 g kg W^− 0.75 d^− 1), and LWG (198 ± 44.6 g d^− 1) not significantly different (P > 0.05). Supplement DMI varied (P < 0.05) from 11.6 g kg W^− 0.75 d^− 1 in Diet 3 to 16.6 g kg W^− 0.75 d^− 1 in Diet 4. In Trial II, 16 pre-weaned local and crossbred calves were involved over 77 d with initial age of calves, Panicum intake, metabolic DMI, and LWG similar (P > 0.05) among crosses. Birthweight varied (P < 0.05) from 17.3 kg for N'Dama × Jersey crosses to 21.2 kg for White Fulani × Brown Swiss crosses. Supplement and total DMI ranged (P < 0.05) from 172 to 483 g d^− 1 for N'Dama × Jersey crosses to 233 and 674 g d^− 1 for non-inseminate or purebred calves, respectively. The LWG in the White Fulani × Brown Swiss and the N'Dama × Jersey calves were respectively 30% and 24% better, though not significantly, than purebred calves. In Trial III, rumen DM degradability characteristics of feeds in three N'Dama steers showed no significant differences (P > 0.05) in slowly degradable fraction (b) and rate of degradation of b (c). Soluble fraction (a), 48-h degradation, potential degradability (PD) and effective degradability (ED) varied significantly (P < 0.05) and were lowest in Panicum, but similar for foliage among the three sweet potato cultivars. Panicum fodder showed improvements in degradation characteristics with supplementation.     

Utilization of nutrients as influenced by different restriction levels of feed intake under sub-tropical conditions in crossbred calves

Twenty growing crossbred calves (mean body wt. 159.7 ± 3.94 kg) were randomly divided into 4 groups 5 in each following randomized block design. To assess the voluntary dry matter intake (VDMI) during preliminary feeding period, all the animals were fed concentrate mixture and wheat straw ad libitum. The lowest DMI amongst all animals fed ad libitum was defined as ‘VDMI’. The animals were fed at four fixed levels. The highest level of DMI was 95% of VDMI (group 1) as determined in preliminary period of feeding the other 3 levels were 80% (group 2), 60% (group 3) and 40% (group 4) of the VDMI. The experimental feeding was continued for a month followed by a metabolism trial. The dry matter intake through concentrate (crushed maize 33, deoiled-soya meal 32, wheat bran 32, mineral mixture 2 and common salt 1 part) and roughage (wheat straw) was 40:60. The DMI (kg/d) and percent of body weight ranged from 1.62 (group 4) to 4.06 (group 1) and 1.20 to 2.58, respectively. The CP intake (g/d) varied from 177 to 442 among 4 groups. The intake of DM, OM, CP, EE, NDF, ADF and hemi-cellulose (g/d or g/kg w^0.75) was also significantly (P < 0.05) different among 4 groups. The digestibility of DM in groups 1, 2, 3 and 4 was 59.9, 61.7, 64.6 and 30.4%, respectively and was significantly (P < 0.05) lower in group 4 as compared to the remaining 3 groups. The digestibility of other all nutrients viz. OM, CP, EE, NDF, ADF and HC was comparable among groups 1, 2 and 3. However, the digestibility of these nutrients was significantly (P < 0.05) lower in group 4 (40% intake) as compared to the other 3 groups. Intake and balance of N was significantly (P < 0.01) different among 4 groups, being the lowest in group 4. Animals of groups 1, 2 and 3 were in positive nitrogen balance, however, animals of group 4 were in negative N balance. The results revealed that nutrient utilization was unaffected up to 60% level but it was drastically reduced at 40% level of feed intake. It was also observed that calves maintained on 80 and 60% of feed intake lost body weight (250–300 g/d).     

Computer-controlled milk replacer feeding strategies for group-reared dairy calves

The objective of this study was to compare the effects of ad libitum and restricted computer-controlled milk replacer (MR) feeding strategies on performance of group-reared dairy calves during preweaning (from 0.5 to 2.0 months of age), weaning (2.0 to 2.5) and postweaning (2.5 to 6.0) periods. Two feeding trials comprised a total of 34 Finnish Ayrshire and 6 Holstein–Friesian bull calves. The calves were randomly (balanced for breed) allotted to pens (5 calves/pen) which were thereafter randomly allotted to two experimental treatments: 1) ad libitum MR feeding (F) with ad libitum access to MR and 2) restricted MR feeding (R) where the calves were given 6.0 L of MR daily. All the calves had free access to water, commercial starter and grass silage before weaning. The weaned calves had free access to water and silage and were given 3 kg/day (air-dry basis) of a concentrate mixture. Due to increased metabolizable energy intake (16.4 vs. 12.7 MJ/day; P < 0.05), the daily gain of the F calves was higher (690 vs. 543 g/day; P < 0.05) than that of the R calves during the preweaning period. Due to the more rapid increase in concentrate intake of the R calves during the weaning period the R calves grew better than the F calves (482 vs. 1038 g/day; P < 0.01) and the differences in live weight evened out during the weaning period. During the postweaning period there were no treatment differences in feed intake or gain. The average gain during the whole study was not affected by either of the treatments. Ad libitum feeding increased the variation in the MR intake and gain compared to restricted feeding.     

半舍饲条件下淘汰母牦牛育肥及犊牦牛培育技术研究

旨在研发半舍饲条件下淘汰母牦牛育肥及犊牦牛培育技术。选取带犊母牦牛和公犊牛各66头,分别随机分为试验组和对照组。在犊牛培育期间（2017年12月4日—2018年3月5日）,对试验组母牦牛进行补饲,试验组犊牦牛断乳前（3月5日断乳）随母牦牛哺乳,并进行补饲;对照组母牦牛不进行补饲,按常规放牧方式饲养,对照组犊牦牛进行断乳并补饲。育肥期间（2018年3月5日至出栏）对试验组母牦牛进行补饲,于6月错峰出栏;对照组母牦牛不进行补饲,于集中出栏时间出售（9月或10月）。在犊牦牛培育期间,观察试验组母牦牛的体重变化情况;每月4日测定2组犊牦牛的体重和体尺指标,并进行统计学分析。计算试验组母牦牛错峰出栏收益。结果表明,在犊牦牛培育阶段,由于试验组犊牦牛随母牦牛哺乳,试验组母牦牛体重平均下降1.17 kg/头;2018年1月4日,试验组犊牦牛的体重极显著（P<0.01）高于对照组,体斜长和胸围显著（P<0.05）高于对照组;2018年2月4日和3月4日,试验组犊牦牛的体重、体高、体斜长、胸围均极显著（P<0.01）高于对照组。试验组母牦牛错峰出栏的效益为1 063.05元。研究结果为提高半舍饲条件下淘汰母牦牛养殖效益以及提升犊牛培育质量提供了技术支撑。     

Essential oils improved weight gain,growth and feed efficiency of young dairy calves fed 18 or 20% crude protein starter diets

The objective was to evaluate interactions between starter protein (180 vs. 200 g/kg, DM basis) and a mixture of essential oils (EOs; containing thymol, eugenol, vanillin, limonene and guaiacol) on growth, metabolic and ruminal functions of Holstein dairy calves. In a completely randomized 2 × 2 factorial design, 48 calves, 3 days old (averaging BW 42.7 ± 1.9 kg), were allocated into groups fed the following diets: (i) 180 g/kg CP with no EO (180P‐NEO); (ii) 180 g/kg CP with EO (180P‐EO); (iii) 200 g/kg CP with no EO (200P‐NEO); and (iv) 200 g/kg CP with EO (200P‐EO). The EO was supplemented as 1 g/kg of starter DM. Calves were fed ad libitum starter diet and were weaned at day 59 of age, but diets continued until day 80. There were no interactive effects of CP and EO on intake and growth. Pre‐weaning feed efficiency tended to be increased for 200P‐EO (p = .09). Average daily gain and feed efficiency during pre‐weaning period as well as weaning weight were increased (p < .05) by EO, whereas wither height was increased by EO (p = .03) and tended to be increased for 200P vs. 180P (p = .06). Post‐weaning blood urea nitrogen concentration tended to be lower in 180P vs. 200P (p = .08). Ruminal short‐chain fatty acids concentration was greatest in 200P‐EO. The EO increased both butyrate (p = .02) and propionate proportions (p = .01) and reduced acetate proportional ratio (p < .01). Ruminal ammonia‐N was tended to be lower in calves‐fed EO (p = .05) and was lower in those fed 180P vs. 200P (p < .01). In conclusion, supplementation of the starter diet with essential oil improved weight gain, growth and feed efficiency of dairy calves, irrespective of dietary protein content.