Dynamic Changes of Intestinal Microbiota and Metabolite Composition in Pre-Weaned Beef Calves

Background: Gut microbes and their metabolites are essential for maintaining host health, but few studies have elucidated the combined effects of microbial and metabolite interactions on the growth and development of pre-weaned calves over time. Therefore, the aim of this study was to explore dynamic changes of intestinal microbiota and metabolites among newborn calves classified as healthy, sub-healthy, and those that died early during their growth and development.Results: 16S rRNA gene sequencing and metabolomics analysis was employed to track the dynamic changes in faecal microflora abundance and metabolite levels (fatty acids and amino acids) in calves before weaning. The results demonstrated that the alpha diversity of the faecal microbiota increased with calf growth and development. Specifically, the abundances of Porphyromonadaceae bacterium DJF B175 and Alistipes shahii gradually increased in healthy calves over time. Inversely, the abundance of Enterobacteriaceae was higher in the sub-healthy group than in the healthy group. Meanwhile, the faeces of calves in the early death group had significantly higher medium-long-chain fatty acid concentration than those in the healthy group. The faecal amino acid concentration decreased significantly with weekly age in the healthy and sub-healthy groups.Conclusions: The study findings provide a new understanding of calf growth and development prior to weaning. Even under the same management conditions, microorganisms and their metabolites interact to play different dynamic regulatory roles in the growth and development of newborn calves. Further studies are warranted to determine the mechanisms involved.

Backfat Thickness Does Affect the Restoration of Ovarian Activity Postpartum in Different Breeding Programs in Zebu Cattle

The backfat thickness (BFT) was used to forecast the onset of ovarian activity and predict the calf growth. Eighty Brahman cows with their calves were allocated in two groups of 40 distributed in 4 months according to the month of calving, starting in March and finishing in June. One was synchronized and inseminated at fixed time following by natural mating (TAI+NM); whilst the other only by natural mating (NM). The programs started at 60 ± 5 days postpartum and ended 60 days later. From day 30 postpartum, serial ultrasound examinations and progesterone samples were used to monitor the onset of ovarian activity. The BFT in the rump area was measured by ultrasound from 30 days postpartum and every 15 days thereafter. The weight of the calves was recorded at birth and at weaning on 160 days. The adjusted effect of BFT on ovarian activity and the calves' development was assessed by binomial logistic regression at 30, 60, 75, and 120 days postpartum. The cycling cows averaged higher BFT irrespective of breeding program (P < 0.001). Also, slower changes in BFT were recorded during the follow-up at each time for all cows. However, the former had the higher BFT values from calving to the end of the study (P < 0.001). At 60, 75, and 120 days, the BFT measured, at the preceding time, was the only factor predicting the commencement of cyclicity (P < 0.001). The accumulative pregnancy through time was higher in TAI+NM (P = 0.003). Daily weight gain and weaning weight of the calves born in March was significantly heavier (P < 0.001) than peers born in April, May, or June. The most critical element to forecast the onset of ovarian activity is the monitoring of BFT around calving regardless of the breeding program. BFT to estimate the development of the calves until weaning was unpredictable.

525 Late-Breaking: Late Gestational Nutrient Restriction of Primiparous Beef Heifers Decreases Milk Yield and Pre-weaning Calf Growth

Fall-calving Hereford-SimAngus heifers (single-sired; BW: 451 ± 28 [SD] kg; BCS: 5.4 ± 0.7) bred to a single sire were individually-fed 100% (control; CON; n = 12) or 70% (nutrient restricted; NR; n = 13) of NASEM net energy and metabolizable protein requirements for maintenance, pregnancy, and growth from d 160 of gestation to calving. Post-calving, all females were limit-fed chopped tall-fescue hay supplemented to meet lactational nutrient requirements in Calan gates to constrain calves’ diets to milk only until d 147. Four-hour milk yields were measured 5 times; calf size was determined every 21 d. Data were analyzed with treatment, calving date, and calf sex (when P < 0.25) as fixed effects; day and day x treatment were included for milk yield. From calving to d 147, CON cows had greater (P ≤ 0.003) BW, BCS, and backfat, but NR cows gained more (P ≤ 0.004) BW, BCS, and backfat. Milk weight and volume was 15% less (main effect; P < 0.04) for NR cows. Calf size did not differ at birth (P ≥ 0.27). From d 42 to 147, calves born to NR dams had lower (P ≤ 0.02) BW. Heart, abdominal, and flank girths were less (P ≤ 0.07) for NR calves through d 147. Calf ribeye area tended to be less (P ≤ 0.11) in NR calves at d 42, 84, and 126. Nutrient restricted calves had less shoulder to rump length (d 63 to 147; P ≤ 0.08), shoulder height (d 63 to 126; P ≤ 0.02), cannon length (d 42 to 105 and 147; P ≤ 0.09), and cannon circumference (d 63 and 105 to 147; P ≤ 0.06). These data indicate that even when dams are fed to meet lactational requirements, milk yield and calf growth are reduced by late gestational nutrient restriction.

290 Encapsulated Sodium Butyrate (Ultramix GF) for Transitioning Neonatal Calves from Milk to Calf Starter

Butyrate (UltraMix GF; Adisseo) is known to enhance ruminal papillae development for transitioning calves to dry feed. The hypothesis was that butyrate would be beneficial to neonatal calf growth performance. Eighty 2- to 5-d old Holstein bull calves were assigned to one of 2 treatments using a randomized complete block design. Treatments were: 1) control: no butyrate; or 2) butyrate: 0.3% butyrate added to milk replacer (MR). Calves were fed 2x/d at 0630 and 1800 h along with free choice water and a 22% CP mini-pelleted calf starter (CS). The MR was fed at 0.567 kg/d for d 1–14, then increased to 0.85 kg/d for d 15–42, and feeding reduced to 1x/d for d 42–49 with weaning occurring after the 49-d experimental period. Calves fed butyrate demonstrated greater (P < 0.04) ending body weight (BW; 54.7 and 56.2 kg, for control and butyrate, respectively), BW gain (29.0 and 31.7 kg), and average daily gains (ADG; 591.3 and 647.7 g/d), compared with calves fed control. Dry matter intake (DMI) was similar (P > 0.10) for both treatments, but the number of d required for calves to consume 0.9 kg CS for 3 consecutive days (47.3 and 45.7 d) was lower (P < 0.05) for calves fed butyrate compared with calves fed control. Feed conversions were improved (P < 0.05) for calves fed butyrate (0.53 and 0.58 kg/kg) compared with calves fed control. At the end of the 49-d study, withers height tended (P < 0.10) to be greater for calves fed butyrate (85.2 and 86.0 cm) compared with calves fed control, while the remaining frame measurements (hip height, hip width, body length, and heart girth) and fecal scores were similar (P > 0.10) for calves fed both treatments. Feeding neonatal calves butyrate in the MR improved growth performance and reduced the days to transition calves to CS.

291 Weaned Holstein Calves Fed an Experimental Botanical Extract Alone or in Combination with an Eubiotic Product

A botanical extract (BE; garlic oil, anise oil, cinnamaldehyde, rosemary, and thyme blend) has been shown to enhance dry matter intake (DMI) and gut health, while eubiotics (EU; lactobacillus acidophilus fermentation product), has been shown to improve gut health and growth performance of growing Holstein calves. The hypothesis was the combination BE and EU could be synergistic to post-weaning neonatal calf growth performance. Seventy-seven (77) Holstein bull calves from a previous milk replacer trial were randomly assigned to 1 of 4 treatments using a 3 wk experimental period. Treatments were: 1) Control: Calf starter (CS) without BE or EU; 2) BE: CS with 275.6 g/ton of an experimental BE (Adisseo North America, Alpharetta, GA); 3) EU: CS with 0.22% EU (RumaCell DF 5G; Pacer Technology, Murtaugh, ID); and 4) BE&EU: CS with added BE and EU. The 22% crude protein CS was a mini-pellet and fed for ad-libitum consumption with amounts fed and orts recorded daily. Calves fed EU demonstrated greater (P < 0.05) body weight (BW; 81.3, 80.8, 84.8, and 84.2 kg for Control, BE, EU, and BE&EU, respectively) compared with calves fed Control and BE with calves fed BE&EU being intermediate and similar (P > 0.10). Calves fed BE demonstrated greater (P < 0.05) average daily gains (ADG; 965.5, 984.3, 1052.8 and 989.1 g/d) compared with calves fed Control with calves fed BE and BE&EU being intermediate and similar (P > 0.10). The DMI (2.19, 2.18, 2.31, and 2.14 kg/d) and feed conversions (0.45, 0.46, 0.45, and 0.45 kg BW gain/kg DMI) were similar (P > 0.10) among calves fed all treatments. Blood urea nitrogen concentrations (14.7, 14.6, 14.9, and 13.4 mg/dL) were similar (P > 0.10) among calves fed all treatments. Feeding a EU improved BW of weaned growing Holstein bull calves, but the BE and EU combination was not beneficial for enhancing growth performance.

Effects of supplementing lactating camels with Acacia tortilis pods and ‘Chalbi salt’ on milk yield and calf growth in the peri-urban area of Marsabit town, Kenya

Camel milk production and marketing within the peri-urban areas within pastoral areas is emerging and has high potential due to sendentarization and urbanization of an increasing number of local inhabitants. Performance of grazing camels in these areas is poor due to inadequate feed resources, particularly during the dry season. The objective of this study was to determine the effect of supplementing lactating camels with milled Acacia tortilis pods and ‘Chalbi salt’ on milk yield, calf growth and its economic potential in the peri-urban area of Marsabit town, Kenya. Twenty Somali camels in early lactation (1-4 weeks post-partum) and parities 2 or 3 and their calves were recruited for the study. The dams and their calves were penned and fed individually with the supplements where applicable. The treatments were: browsing only (B), browsing and ‘Chalbi salt’ (BC), 2 kg/day milled Acacia tortilis pods, ‘Chalbi salt’ and browsing (BC2A) and 4 kg/day milled Acacia tortilis pods, ‘Chalbi salt’ and browsing (BC4A). Five camels were randomly allocated to each treatment based on initial live weight in a completely randomized design and data collection done for 90 days. During each milking, the two left or right quarters were alternately reserved for the calf, while the remaining two were milked by hand. Milk yields were recorded daily in the morning and evening for 90 days while the calves were weighed on weekly basis for the same period. The overall total mean milk yield during the experimental period ranged from 233.0 to 298.0 litres during the short rains and dry season, respectively. The mean calf weight gains over the study period were 15.2, 19.0, 32.2 and 39.0 kg for B, BC, BC2A and BC4A, respectively, with BC4A and BC2A being higher than B. Supplementing camels under treatment BC4A was profitable as it resulted in both higher milk yield and calf weight gain and hence positive net gain. Int. J. Agril. Res. Innov. Tech. 11(1): 117-122, June 2021

FEATURES OF GROWTH OF CALVES DURING THE DAIRY PERIOD WHEN USING PHYTOPREPARATIONS

Изучены особенности роста и развития молодняка крупного рогатого скота при выращивании в ранний период онтогенеза после применения фитосредств на основе водно-дисперсной вытяжки из древесины березы и лиственницы, позволяющих активировать обменные процессы в организме и повышать прирост живой массы телят соответственно на 20,3 и 34,5%. Гематологические исследования показывают, что интенсивный рост молодняка сопровождается динамикой содержания в сыворотке крови белка, кальция, фосфора, глюкозы, щелочной фосфатазы, которые в дальнейшем можно использовать в качестве тестов для раннего прогнозирования роста телят в промышленных комплексах. The features of growth and development of young cattle during growth in the early period of ontogenesis after using the phytosupplements on the basis of a water dispersed extract from birch and larch wood allowing to activate metabolic processes in an organism and to increase a gain of live weight of calves by 20,3 and 34,5% respectively have been studied. Hematological studies show that the intensive growth of young calves is accompanied by the dynamics of serum protein, calcium, phosphorus, glucose, alkaline phosphatase, which can be further used as a test for early prediction of calf growth in industrial complexes.

Effects of supplements differing in fatty acid profile to late gestational beef cows on cow performance, calf growth performance, and mRNA expression of genes associated with myogenesis and adipogenesis

Background Maternal nutrition during gestation affects fetal development, which has long-term programming effects on offspring postnatal growth performance. With a critical role in protein and lipid metabolism, essential fatty acids can influence the development of muscle and adipose tissue. The experiment investigated the effects of late gestation supplements (77 d prepartum), either rich in saturated and monounsaturated fatty acids (CON; 155 g/cow/d EnerGII) or polyunsaturated fatty acids (PUFA; 80 g/cow/d Strata and 80 g/cow/d Prequel), on cow performance and subsequent calf growth performance as well as mRNA expression in longissimus muscle (LM) and subcutaneous adipose tissue at birth and weaning. Results There was no difference (P ≥ 0.34) in cow body weight (BW) or body condition score from pre-supplementation through weaning. Relative concentrations of C18:3n-3 and C20:4n-6 decreased (P ≤ 0.05) to a greater extent from mid-supplementation to calving for PUFA compared with CON cows. Cow plasma C20:0, C20:5n-3, and C22:6n-3 were increased (P ≤ 0.01) in PUFA during supplementation period. At birth, PUFA steers had greater (P = 0.01) plasma C20:5n-3. No differences (P ≥ 0.33) were detected in steer birth BW or dam milk production, however, CON steers tended (P = 0.06) to have greater pre-weaning average daily gain and had greater (P = 0.05) weaning BW compared with PUFA. For mRNA expression in steers: MYH7 and C/EBPβ in LM increased (P ≤ 0.04) to a greater extent from birth to weaning for PUFA compared with CON; MYF5 in LM and C/EBPβ in adipose tissue tended (P ≤ 0.08) to decrease more from birth to weaning for CON compared with PUFA; SCD in PUFA adipose tissue tended (P = 0.08) to decrease to a greater extent from birth to weaning than CON. In addition, maternal PUFA supplementation tended (P = 0.08) to decrease MYOG mRNA expression in LM and decreased (P = 0.02) ZFP423 in adipose tissue during the pre-weaning stage. Conclusions Late gestation PUFA supplementation decreased pre-weaning growth performance of the subsequent steer progeny compared with CON supplementation, which could have been a result of downregulated mRNA expression of myogenic genes during pre-weaning period.

47 Effects of Lactobacillus and Bacillus Probiotics on Pre-ruminating Calf Growth Performance and Efficiency

Lactobacillus and Bacillus probiotics may serve as an alternative to antibiotics in milk replacer for pre-ruminant calves by altering gastrointestinal microflora to prevent the proliferation of harmful bacteria. However, there are limited studies evaluating their impact on calf growth and efficiency. The objective of this trial was to discover the impact of probiotic-containing milk replacer on pre-ruminating calf growth performance. A total of 44 pre-ruminant calves (50% Angus/50% Holstein, average weight 39.3 kg + 7.5 kg) were fed milk replacer with either no probiotic or 1.25x10^9 colony forming units/head/day of a probiotic blending containing Lactobacillus and two different Bacillus species (Church & Dwight Animal Nutrition (Princeton, NJ). Calves were blocked by age and randomly assigned within block to one of two treatments in a randomized complete block design. Calf was the experimental unit, with 22 calves per treatment. Calf weight and hip height was measured on d 0 and 30 to calculate average daily gain (ADG) and average growth per day. Calves were offered 1.36 kg milk replacer [15% dry matter (DM)] twice daily and up to 0.5 kg starter feed (88% DM) once daily. Refusals were recorded to calculate average daily intake and gain to feed ratio (G:F). Initial weight differed (P = 0.020) between treatments, and was therefore used as a covariate in all response criteria. Calves fed milk replacer with probiotic had greater (P < 0.05) ADG (0.53 vs. 0.42 kg/d, respectively) and G:F (0.50 vs. 0.41, respectively) than those fed the control. There was no evidence (P >0.05) that probiotic inclusion impacted hip height on d 30 or daily intake. In summary, Lactobacillus and Bacillus probiotic inclusion in milk replacer improved calf growth performance without impacting intake. Subsequent research is warranted to elucidate mode of action and evaluate impact relative to an antibiotic-containing positive control.

Water sprinkling as a tool for heat abatement in farmed Iberian red deer: Effects on calf growth and behaviour

Climatic models predict scenarios in which ambient temperature will continue increasing worldwide. Under these climatic conditions, fitness and animal welfare of many populations are expected to suffer, especially those that live in captive or semi-natural conditions, where opportunities of heat abatement are limited. We undertook an experimental design to assess the effect of heat abatement that water sprinkling might have on Iberian red deer calf growth and behaviour from birth to weaning (135 days). One group of ten mother-calf pairs lived on plots with water sprinkling (treatment) available during summer’s hottest time of the day, while the control group (nine mother-calf pairs) occupied plots with no available water sprinkling. Treatment and control groups were fed ad libitum and swapped between plots every seven days to minimise any plot effect. Body weight was monitored weekly and individual behaviour was recorded once or twice a week at mid-day. We observed that calves had showers under the sprinklers and wallowed in mud puddles. The results clearly indicated that calves of the treatment group showed a significant increase in body weight at weaning in comparison with the control group, with no differences between sexes (treatment: male = 56.5 kg, female = 50.3 kg; control: male = 50.3 kg, female = 46.5 kg). Mother weight and mother age effects were negligible on calf body weight at weaning. The heavier the mother the faster was the rate of growth of its offspring, irrespective of calf sex. The model indicated that although males grew significantly slower than female calves in the control group, males grew faster than females when exposed to the treatment. Calves of the treatment group spent less time drinking, less time in the shade, similar time eating and more time in motion than calves of the control group. There were no behavioural differences between calf sexes of treatment and control groups. The results indicate the importance of providing animals with opportunities of heat abatement in hot environments to improve animal growth and welfare in farmed Iberian red deer.