Effects of mannan‐oligosaccharides and Lactobacillus acidophilus supplementation on growth performance,nutrient utilization and faecal characteristics in Murrah buffalo calves

A study of 120 days was undertaken to ascertain the effect of mannan‐oligosaccharides (MOS) and Lactobacillus acidophilus supplementation on growth performance, nutrient utilization and faecal characteristics in Murrah buffalo calves. Twenty Murrah buffalo calves of 5–7 days old and 31 ± 2.0 kg of body weight (BW) were randomly assigned into four groups. Group I served as the control (CON) in which only basal diet (concentrate mixture and green fodder) was provided, without any supplementation. Mannan‐oligosaccharides at 4 g/calf/day were supplemented as prebiotic to Group II (PRE), whereas Group III (PRO) received Lactobacillus acidophilus in the form of fermented milk as probiotic at 200 ml/calf/day having 10⁸ CFU/ml and Group IV (SYN) was supplemented with both MOS and Lactobacillus acidophilus as synbiotic at similar dose. Final BW (kg), dry matter intake, average daily gain, feed conversion efficiency and structural growth measurements were improved (p < .05) in the treatment groups compared to control. Digestibility of neutral detergent fibre was higher (p < .05) in SYN followed by PRE and PRO than control. The faecal lactobacilli and bifidobacterium population was higher (p < .05) in all the supplemented groups with a concomitant reduction in faecal coliform count as compared to control. Faecal ammonia, lactate and pH were also altered favourably (p < .05) in all the supplemented groups as compared to CON. The faecal volatile fatty acids were higher (p < .05) in PRE, PRO and SYN group than CON. The incorporation of MOS and Lactobacillus acidophilus in diet either individually or in combination as synbiotic has the potential to improve the performance and faecal characteristics in Murrah buffalo calves; however, the observed responses among the treatment groups were more evident in the synbiotic fed group compared to individual supplementation of MOS and Lactobacillus acidophilus.     

Effects of two different rearing protocols for Holstein bull calves in the first 3 weeks of life on health status,metabolism and subsequent performance

The aim of this study was to investigate the impact of weight gain of calves within the first 3 weeks of life on health status and subsequent performance. Holstein bull calves were reared either intensively (IR; individual hutches and ad libitum milk feeding for the first 3 weeks of life; n = 24), or according to the established protocol [ER; 4 l milk/day in hutches during week 1 and 720 g/day milk replacer (MR) from day 8 to 21 in a group pen; n = 24]. Water, hay and concentrates were freely available to all calves. From week 4, calves of both groups were housed together in a group pen and fed 720 g MR/day; step‐down weaning was performed between week 5 and 10. Key metabolic blood parameters were analysed on day 2, 12, 21 and 70 of life. After weaning, all animals were fed concentrates and corn silage until slaughter at an age of 8 months. Within the first 3 weeks, average daily weight gain was threefold higher in IR calves in relation to ER calves (1.28 vs. 0.38 kg/day, p < 0.001). Neither incidence nor duration of scouring differed significantly between groups. Starter intake (week 4–10) was higher in IR calves in relation to ER calves (49.7 vs. 38.0 kg/calf, p = 0.006). Serum glucose, urea, albumin and insulin were higher at an age of 21 days in IR calves in relation to ER calves; no differences were obvious at an age of 70 days. Plasma GH and IGF‐I concentrations revealed an uncoupling of the somatotropic axis in ER calves within the first 3 weeks of life. At slaughter, body weight of IR calves tended to be higher than that of the ER calves (320 vs. 309 kg, p = 0.07). In conclusion, intensive feeding and individual housing during the first 3 weeks of life had positive long‐term effects on subsequent performance.     

The effect of dietary garlic supplementation on body weight gain,feed intake,feed conversion efficiency,faecal score,faecal coliform count and feeding cost in crossbred dairy calves

Thirty-six crossbred calves (Holstein cross) of 5 days of age were used to study the effect of garlic extract feeding on their performance up to the age of 2 months (pre-ruminant stage). They were randomly allotted into treatment and control groups (18 numbers in each group). Performance was evaluated by measuring average body weight (BW) gain, feed intake (dry matter (DM), total digestible nutrient (TDN) and crude protein (CP)), feed conversion efficiency (FCE; DM, TDN and CP), faecal score, faecal coliform count and feeding cost. Diets were the same for the both groups. In addition, treatment group received garlic extract supplementation at 250 mg/kg BW per day per calf. Body weight measured weekly, feed intake measured twice daily, proximate analysis of feeds and fodders analysed weekly, faecal scores monitored daily and faecal coliform count done weekly. There was significant increase in average body weight gain, feed intake and FCE and significant decrease in severity of scours as measured by faecal score and faecal coliform count in the treatment group compared to the control group (P < 0.01). Feed cost per kilogramme BW gain was significantly lower in the treatment group compared to control group (P < 0.01). The results suggest that garlic extract can be supplemented to the calves for better performance.     

Influence of dietary supplementation of prebiotics (mannanoligosaccharide) on the performance of crossbred calves

Thirty-six Holstein cross calves 5 days of age in their preruminant stage were used to study the effect of feeding prebiotic (mannanoligosaccharide) on their performance up to the age of 2 months. Treatment and control groups consisted of 18 calves each. Treatment group was supplemented with 4 g prebiotic (mannanoligosaccharide)/calf/day. Performance was evaluated by measuring average body weight (BW) gain, feed intake [dry matter (DM), total digestible nutrient (TDN) and crude protein(CP)], feed conversion efficiency (DM, TDN, and CP), fecal score, fecal coliform count and feeding cost. Body weight measured weekly, feed intake measured twice daily, proximate analysis of feeds and fodders analyzed weekly, fecal score monitored daily and fecal coliform count done weekly. There was a significant increase in average body weight gain, feed intake and feed conversion efficiency; and a significant decrease in severity of scours as measured by fecal score and fecal coliform count in the treatment group compared with control group (P < 0.01). Feed cost/kg BW gain was significantly lower in the treatment group compared to control group (P < 0.01). The results suggest that prebiotic (mannanoligosaccharide) can be supplemented to the calves for better performance.     

Effects of limited concentrate feeding on growth and blood and serum variables, and on nutrient digestibility and gene expression of hepatic gluconeogenic enzymes in dairy calves

This study elucidated the effects of limited concentrate feeding on growth, nutrient digestibility, blood profile and gene expression of gluconeogenic enzymes in the liver of dairy calves. The study utilized 36 German Holstein dairy calves (5-7 days of age) divided into two groups of 18 calves each for 150 days. Control group calves received 2 kg/(calf × day) of concentrate, whereas calves in the restricted group received only 1 kg/(calf × day). Good quality forage (mixture of maize and grass silages) was available for ad libitum consumption to both groups. The intake of milk replacer before weaning, and of concentrate were recorded daily per calf; however, the consumption of forages was quantified as daily average of the group. Body weights (BW) were recorded at start and on days 35, 70, 112 and 150. Blood and serum samples and spot urinary and faecal samples were also collected at similar time points. On days 70 and 150, liver biopsies were collected from seven animals in each group. The BW was not different between the groups at all times. Total BW gain in the control group was 124 kg as opposed to 111 kg in restricted group that led to average BW gain of 827 g/day and 739 g/day in respective groups, and the differences were significant (p = 0.018). As planned, the control group had higher concentrate and lower forage intake than the restricted group. The blood haemoglobin, haematocrit and serum variables (glucose, total protein, albumin and urea) were within the normal range in both groups, but serum glucose was higher (p < 0.05) in control than in restricted group at 70 days. There was no difference between groups in organic matter (OM) digestibility which declined (p < 0.001) with increasing age in both groups. Microbial crude protein (MCP) synthesis estimated from urinary allantoin excretion increased (p < 0.001) in both groups with increasing age but was not different between groups. The mRNA expressions for the gluconeogenic enzymes, cytosolic and mitochondrial phosphoenol pyruvate carboxykinase (EC 4.1.1.32) and pyruvate carboxylase (EC 6.4.1.1) measured by quantitative real-time PCR in liver biopsies showed no differences between groups. Overall, restricting concentrate moderately reduced the growth intensity without affecting the normal serum and blood indices, and MCP synthesis and OM digestibility showed no differences between groups, indicating that both concentrate feeding schemes can be successfully applied.     

Plane of nutrition affects growth rate,organ size and skeletal muscle satellite cell activity in newborn calves

Plane of nutrition effects on body, tissue and cellular growth in the neonatal calf are poorly understood. The hypothesis that a low plane of nutrition (LPN) would limit skeletal muscle size by reducing fibre growth and muscle progenitor cell activity was tested. At birth, calves were randomly assigned to either a LPN (20% CP, 20% fat; GE=1.9 Mcal/days) or a high plane of nutrition (HPN; 27% CP, 10% fat, GE = 3.8 Mcal/days) in a 2 × 3 factorial design to test the impact of diet on neonatal calf growth, organ weight and skeletal muscle morphometry with time. Groups of calves (n = 4 or 5) were euthanised at 2, 4 and 8 week of age and organ and empty carcass weights were recorded. Body composition was measured by DXA. Longissimus muscle (LM) fibre cross‐sectional area (CSA), fibre/mm² and Pax7 were measured by immunohistology. Satellite cells were isolated at each time point and proliferation rates were measured by EdU incorporation. Calves fed a HPN had greater (p < 0.05) BW, ADG and hip height than those fed a LPN for 2, 4 or 8 weeks. HPN calves contained a greater (p < 0.05) percentage of fat tissue than LPN calves. Liver, spleen and thymus weights were less (p < 0.05) in LPN calves than HPN animals. Calves fed HPN had larger (p < 0.05) LM CSA at 8 weeks than LPN fed animals with no differences between the groups in numbers of satellite cells per fibre. Proliferation rates of satellite cells isolated from HPN fed calves were greater (p < 0.05) at 2 weeks than LPN fed animals, which exhibited greater (p < 0.05) proliferation rates at 4 weeks than HPN fed calves. We conclude a LPN diet reduces body growth and organ size and metabolically reprograms satellite cell activity.     

The labour input associated with calf care on Irish dairy farms

The objective of this study was to quantify the overall labour requirement for calf care and how it is influenced by enterprise scale and facilities, together with an evaluation of specific calf-feeding systems with respect to labour requirement and calf performance. One hundred and twenty nine spring-calving dairy herds participated in the investigation of overall labour input. Herds were categorized into three groups depending on herd size (small = < 50 cows, medium = 50 to 80 cows, large = > 80 cows). The total average time consumed by calf care per farm increased (P < 0.01) with herd size and the average time consumed per calf was highest in the small herd group (2.1 min/day). The proportion of farms bucket feeding was lower (P < 0.05) and the proportion feeding calves ad libitum and using cold milk was higher (P < 0.05) with the large group compared to the small herd group. Fifty-seven of the 129 herds participated in the measurement of labour input associated with specific calf-feeding systems. The labour input time per calf required for the task of milk feeding tended (P = 0.08) to be longer when calves were fed twice daily, using buckets or teats compared to automatic feeders, once daily feeding with teats and twice daily feeding with a trough. The labour input per calf for the cleaning of milk feeding equipment and for bedding and cleaning calf pens was greater (P < 0.05) with automatic feeding systems compared to the other feeding systems. A further sub-set of ten herds (from the 57 herds) underwent calf performance measurements. The mean calf weight at day 77 for automatic feeding, once daily feeding, twice daily feeding with teats and twice daily feeding with troughs was 95, 95, 93, 91 kg, respectively. In conclusion, labour input associated with calf care was influenced by herd size (and indirectly calf number), and calf-feeding system. Milk feeding of calves on a once daily basis tended to reduce the total labour input per calf and did not adversely affect calf performance. Thus, it is possible to improve efficiency of calf care by selecting time efficient methods of calf-feeding without affecting calf performance.     

Effects of Allium mongolicum Regel supplementation on the digestibility,methane production,and antioxidant capacity of Simmental calves in northwest China

This study evaluated the effects of Allium mongolicum Regel (AM) supplementation on nitrogen (N) balance, ruminal fermentation, and antioxidant properties. Sixteen male calves were assigned randomly to four groups, and the four were added with 0 (CON), 200 mg/kg (body weight; BW) (Low AM; LA), 400 mg/kg (BW) (Middle AM; MA), or 800 mg/kg (BW) (High AM; HA) per day for each individual. AM was added on dry matter (DM) basis. The experiment lasted for 58 days. Supplementation of AM could significantly increase average daily gain, DM digestibility, acid detergent fiber digestibility, and retained N/Intake N. N digestibility and molar proportion of propionate in the MA and HA treatments were higher than that in the CON treatment (p < .05), respectively. AM supplementation significantly increased the molar concentration of total volatile fatty acid in the rumen fluid (p < .05). The ratio of acetate to propionate in the MA and HA groups was lower than that in the CON treatment (p < .05). Furthermore, AM supplementation significantly reduced methane (CH₄) (p < .05) emissions. AM supplementation significantly increased the activities of superoxide dismutase. The MA group could significantly increase the activities of glutathione peroxidase and decrease the content of malondialdehyde. Our results indicated that AM supplementation could affect the nutrient digestibility, CH₄ emission, and antioxidant capacity of Simmental calves.     

Effect of dietary concentrate content on feed intake,feed efficiency,and meat quality of Holstein steers fattened in a hot environment

The objective of this study was to investigate the effect of feeding high and low concentrate diets on feed intake and feed efficiency, the morphological characteristics of the rumen papillae, and meat quality of Holstein steers fattened under hot climate conditions in Oman. Ten male Holstein calves, of 5 months of age, were selected for the experiment. The animals were fed concentrate and Rhodes grass hay and were divided into two groups of high concentrate (HC, n = 5) and low concentrate diets (LC, n = 5), in which their feed intake, weight gain, and feed efficiency were evaluated across three growing periods. Feed intake and efficiency and average daily gain (ADG) of the HC group were significantly greater than for the LC group and were affected by the diet (p < .01) and the period (p < .001). Across the fattening periods, ADG declined in both groups, with ADG improved by 35% for steers on the HC diet compared to steers on the LC diet. Carcass meat quality was not affected significantly by the dietary concentrate level. In conclusion, our results can be used to make improvements in feed efficiency of Holstein steers under hot climate conditions.     

Erythrocyte Lipid Peroxides and Blood Zinc and Copper Concentrations in Acute Undifferentiated Diarrhoea in Calves

Undifferentiated acute calf diarrhoea is a major concern for the dairy industry and its aetiopathogenesis remains diverse. The present study aimed to examine the role of oxidative stress through estimation of erythrocyte lipid peroxide levels and blood zinc and copper concentrations using natural cases of diarrhoea in calves aged 15–30 days old. The calves were kept under identical managemental conditions and were provided with pooled whole colostrum during the first three days and thereafter with only whole milk until they were 1 month old. Diarrhoeic (n = 11) and normal calves (n = 11) of the same age group (15–30 days old) were randomly selected from an organized dairy farm for the study. The mean blood zinc concentration (50.01±2.45 μmol/L vs 66.06±3.06 μmol/L) was significantly (p < 0.05) lower and copper concentration was significantly (p < 0.05) higher in diarrhoeic calves (12.90±0.31 μmol/L vs. 9.44±0.16 μmol/L) than in the healthy calves. The erythrocyte lipid peroxides level was higher (p < 0.05) in diarrhoeic calves (6.88±0.23 nmol malondialdehyde (MDA) per mg of haemoglobin (Hb)) than healthy calves (6.27±0.07 nmol MDA per mg Hb). From the results of the study it is concluded that oxidative stress and antioxidant minerals (zinc and copper) might play important roles in the aetiopathogenesis of bovine calf diarrhoea.     

Biological and biochemical characteristics of male reproductive system,serum metabolites and carcass quality of Japanese quails by the supplementation of Pinus ponderosa leaves and α‐tocopherol acetate

The aim of the current study was to evaluate the effect of dietary supplementation of Pinus ponderosa leaves ( pine leaves) and α‐tocopherol acetate (vitamin E) powder on male reproductive system, serum metabolites and carcass characteristics of Japanese quails. A total of 360‐day‐old male quails were purchased from the open market and kept at poultry shed for ninety‐four days. After ten days of adaptation, all quails were randomly assigned into 4 groups, control (IC); supplemented with α‐tocopherol acetate (IE) at the rate of 150 mg/L; Pinus ponderosa leaves (IP) at the rate of 150 mg/L; and 70 mg α‐tocopherol acetate and 70 mg Pinus ponderosa leaves (IEP). Pinus ponderosa leaves and α‐tocopherol acetate supplementation had not significantly (p > .05) effected on final body weight gain, feed intake and feed conversion ratio of quails. The high‐density lipoprotein cholesterol (HDLC) and total cholesterol (TC) were significantly (p > .05) affected by IE and IP groups as compared to IC and IEP groups. Triglyceride (TG), glutathione peroxidase (GPx) and superoxide dismutase (SOD) significantly (p < .05) increased in all treatment groups except for the IC group. Aspartate transaminase (AST) significantly (p > .05) decreased in treatment groups as compared to control group. Overall, the mineral levels significantly (p < .05) increased in treatment groups as compared to control. Cloacal gland index values, the quantity of foam production and testis weight were significantly (p < .05) increased in treatment groups. It was concluded that the supplementation of Pinus ponderosa leaves and α‐tocopherol acetate improved the testis weight, foam production, serum antioxidant enzymes and mineral level especially zinc in Japanese quail considered an indicative characteristic of higher sperm production rate and improved sexual activity. Further, higher gametogenesis rate, sperm production or reproductive behaviour including different hormonal level will be analysed in future study.     

Effects of butyrate supplementation in antibiotic‐free milk replacer and starter on growth performance in suckling calves

The aim of this study was to evaluate butyrate supplementation of antibiotic‐free milk replacer and starter on growth performance in male Holstein calves. Twenty‐nine calves were divided into two groups. Group C (n = 13) was fed antibiotic‐free milk replacer without supplementation, and Group B (n = 16) was fed antibiotic‐free milk replacer supplemented with butyrate (1.6 % DM of Gustor BP70^®). Starter in Group B contained 0.3 % DM of Gustor BP70^®. The intake of milk replacer was lower in group B than in C (p = 0.07 for the treatment x week interaction). Body weight (BW) and heart girth (HG) in group B was higher than in C during the experimental period (p = 0.07 and 0.01 for the treatment × week interaction, respectively). The duration of the weaning period in group B was shorter than in group C (p = 0.02). β‐hydroxybutyrate (BHBA) was higher in group B than in C (p = 0.04). Insulin like growth factor‐1 (IGF‐1) concentrations tended to be higher in group B than in C (p = 0.07 for treatment × week interaction). Our results show that butyrate supplementation in antibiotic‐free milk replacer and starter exerted positive effects on growth performance in suckling calves.     

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.     

Effects of animal type (wild vs. domestic) and diet alfalfa level on intake and digestibility of European adult rabbits (Oryctolagus cuniculus)

The aim of this study was to evaluate the effect of the level of alfalfa in the diet on feed intake and digestibility of two types of rabbits, wild (Oryctolagus cuniculus algirus) vs. domestic (O. cuniculus cuniculus). Ten wild (W; mean LW = 927 g) and 10 domestic (D; mean LW = 4,645 g) adult rabbit does were fed ad libitum two pelleted diets: a control diet (C) with 15% of dehydrated alfalfa hay (as feed basis) and a test diet (A) with 36% of dehydrated alfalfa hay (as feed basis), according to a change‐over design. Wild does dry matter (DM) intake per kg live weight (BW) was 55% higher (p < .001) than the intake of the D ones (58 g vs. 37 g DM per kg BW respectively). However, no difference (p > .05) was found when intake was expressed per kg^0.75 BW (ca. 56 g DM) and tended to be higher (p = .07) in D does when expressed per kg^0.67 BW (62 g vs. 55 g DM). Domestic does showed a higher (p < .05) DM, organic matter, crude energy and neutral detergent fibre digestibility (3; 2; 3; 3 percentage points respectively) than W does. The amount of nutrients and energy digested by D does was lower per kg BW (p < .001), similar per kg^0.75 BW (p > .05) and tended to be higher per kg^0.67 BW (p < .1) than in W does. The diet content of alfalfa did not affect (p > .05) the feed intake nor the diet digestibility. This study suggests that W rabbits exhibit a higher intake per kg BW and a lower digestibility than their D counterparts, which results in similar digestible nutrient and energy intake per kg BW powered to 0.75. The nutritive value of dehydrated alfalfa for rabbits, evaluated through intake and digestibility, seems to be equivalent to their base diets (forage plus concentrate).     

Adrenal cortex reactivity in dairy cows differs between lactational stages and between different feeding levels

Changes in ACTH challenge test characteristics in dairy cows changing their physiological status at different lactational stages and different feeding levels were not investigated in terms of repeatability yet. In 23 multiparous Holstein cows (10 cows fed a sole fresh herbage diet without concentrate, 13 cows fed with concentrate), three ACTH challenge tests were performed: once during pregnancy shortly prior to drying off ( T1 ), and in week 3 ( T2 ) and 8 ( T3 ) after parturition. Test characteristics were correlated to performance and metabolic parameters: DMI, BW, energy balance (EB), plasma concentrations of free fatty acids (NEFA) and beta‐hydroxybutyrate (BHB). Basal plasma cortisol concentrations were higher at T1 compared with T2 and T3 (p < .05). The adrenal cortex sensitivity (expressed as total AUC (AUC_t) of cortisol response after ACTH application) was lowest at T2 compared with T1 and T3 (p < .05). Ranking of the individual animals’ responses was not repeatable between time points of the ACTH tests. Enhancing the energy deficiency during early lactation by omission of concentrate did not affect baseline cortisol concentrations in plasma, but decreased peak height at T2 (p < .05). Baseline plasma cortisol concentrations were positively correlated with cortisol peak values after ACTH application, previous lactation performance, milk yield and BW (p < .05). The AUC_t was positively correlated with baseline cortisol concentrations, EB and DMI. Cortisol release after ACTH injection was lower in animals with high plasma concentrations of NEFA, BHB and with higher contents of fat and free fatty acids in milk (p < .05). Cortisol peak height after ACTH administration was higher in cows with a more positive EB, higher DMI and lower plasma concentrations of NEFA and BHB. In summary, cortisol responses to ACTH challenges in this study were not repeatable in dairy cows changing their physiological status.     

Effect of Megasphaera elsdenii NCIMB 41125 dosing on rumen development,volatile fatty acid production and blood β‐hydroxybutyrate in neonatal dairy calves

Thirty calves were randomly assigned to two treatments and fed until weaning [42 days (d) of age]. Treatments were a control group (n = 15), which did not receive Megasphaera elsdenii (Me0) and a M. elsdenii group, which received a 50‐ml oral dose of M. elsdenii NCIMB 41125 (10⁸ CFU/ml) at day 14 day of age (Me14). Calves were given colostrum for the first 3 day followed by limited whole milk feeding. A commercial calf starter was offered ad libitum starting at day 4 until the end of the study. Fresh water was available throughout the study. Feed intake and growth were measured. Blood samples were collected via jugular venipuncture to determine β‐hydroxybutyrate (BHBA) concentrations. Fourteen male calves (seven per group) were euthanised on day 42 and digestive tracts harvested. Reticulo‐rumen weight was determined and rumen tissue samples collected from the cranial and caudal sacs of the ventral and dorsal portions of the rumen for measurements of papillae length, papillae width and rumen wall thickness. Dosing with M. elsdenii NCIMB 41125 improved starter dry matter intake (DMI), weaning body weight (BW) and tended to improve average daily gain. Calves in Me14 group had greater plasma BHBA concentration than Me0‐calves during the last 3 weeks of the trial and had at day 42 greater reticulo‐rumen weight, papillae width and papillae density compared to Me0. No differences in rumen wall thickness or papillae length were observed between the two groups. Total volatile fatty acids, acetate and propionate production did not differ between treatments, but butyrate production was greater in Me14 than Me0. Dosing M. elsdenii NCIMB 41125 showed benefit for calves with improved feed intake and rumen development suggesting increased epithelium metabolism and improved absorption of digestive end products.     

Performance and hemtochemical parameters of buck‐kids fed concentrate partially replaced with tropical Piliostigma thonningii foliage

Fifteen 5‐month‐old Red Sokoto buck‐kids, (6.6 ± 0.71 kg body weight (BW)) randomly distributed into three groups of five animals per group, were used to study the effects of supplementary concentrate partially replaced with Piliostigma thonningii (PT) foliage on the growth performance, economic benefit and blood profile in a completely randomized design using analysis of variance. The goats in group 1 received 100% supplementary concentrates (PT0), groups 2 and 3 received 25% (PT25) and 50% (PT50), respectively, of concentrate replaced with an equal amount (dry matter basis) of Piliostigma foliage. The goats were fed a basal diet of threshed sorghum top (TST). Intake of concentrate, hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, total feeding cost and cost/kg BW were greater (P < 0.05) for PT0 than for PT25 and PT50. Consumption of P. thonningii foliage was greater (P < 0.05) for PT50 relative to PT25. Tannin consumption of the treatment diets were greater (P < 0.05) than that of the control concentrate diet. Serum urea N reduced (P < 0.05) with increasing level of concentrate replacement, while serum glucose was higher (P < 0.05) in PT0 than in PT50. However, means of all blood measurements were within normal ranges for goats. Net benefit showed this rank order: PT0 < PT50 < PT25 (all P < 0.05). Both differential and relative benefits were higher (P < 0.05) for PT25 than for PT50. P. thonningii foliage can replace 50% of supplemental concentrate without impairing feed intake, growth performance and health of buck‐kids.     

Minimum length of the adaptation and collection period in digestibility trials with sheep fed ad libitum only forage or forage plus concentrate

Two in vivo digestibility trials with sheep were conducted to identify the minimum period length of feeding a new diet to obtain reproducible values of nutritional variables onward and the minimum length of collection period as to obtain maximal precision for each variable. Trial 1 was conducted with ten Polwarth male sheep (34 ± 5 kg body weight (BW)) throughout three 21‐day periods, in a completely randomized two‐way crossover design. The animals were divided into two groups (Group A and B, n = 5 per group) which were fed ad libitum with a sequence of the following diets throughout the periods: Group A: hay – hay plus concentrate – hay; Group B: hay plus concentrate – hay – hay plus concentrate. The concentrate was included in a proportion of 0.33 of the total diet. The intake, and the faecal and urinary excretion were measured daily throughout the experiment. For evaluating rumen fermentation variables, in Trial 2 four Santa Inês male sheep (65 ± 5 kg BW) fitted with ruminal cannula were used. The animals were randomly divided into two groups (n = 2 per group), and the trial was conducted through four 21 days experimental period, in a three‐way crossover design, using experimental diets and feeding management similar to Trial 1. The results indicated that, even though no clear or consistent steady‐state condition was identified for rumen fermentation or urinary excretion variables, the adaptation period for measuring OM digestibility in in vivo trials with sheep fed ad libitum where the diet shifts from one of only hay to another containing concentrate, or vice‐versa, should be at least 12 days long. Moreover, although no precision improvement was obtained by increasing the collection period above 1 day for measuring OM digestibility, the minimal length of collection period should be 4 days for measuring faecal excretion variables and 7 days for measuring urinary excretion variables.