Effects of dietary inclusion of Moringa oleifera leaf meal on nutrient digestibility,rumen fermentation,ruminal enzyme activities and growth performance of buffalo calves

This study was conducted to investigate the impact of dietary inclusion of Moringa oleifera leaf meal (MLM) as a substitution for soybean meal on nutrient digestibility, rumen fermentation, rumen enzyme activity, blood metabolites, growth-related hormones, and growth performance of buffalo calves. Thirty buffalo calves eight to nine months of age with an average body weight of approximately 153.7 ± 0.97 kg were randomly distributed through three dietary treatments (ten calves/treatment). MLM inclusion rates were 15% (M15) and 20% (M20), replacing soybean meal by 50 and 75% in the concentrate mixture, respectively. The results indicated that, digestibility of dry matter, organic matter (OM), and crude fiber (CF) increased significantly (p < 0.05) with MLM inclusion, while the digestibility of crude protein (CP) and ether extract (EE) reduced significantly (p < 0.05) with MLM addition. Dietary supplementation with MLM significantly affected (p < 0.001) rumen fermentation by reducing ruminal enzymes, ruminal ammonia-N, total protozoa, and acetate/propionate ratio and increasing acetic, propionic, and butyric acids and total volatile fatty acid concentrations (p < 0.001). Furthermore, dietary inclusion of 15% MLM significantly improved (p < 0.001) final body weight, dry matter intake of feed, daily weight gain, feed conversion efficiency, blood metabolites, and plasma insulin growth factor-I (IGF-I). It can be concluded that MLM is a multi-purpose protein supplement that provides some nutritional and therapeutic advantages when replacing 50% of soybean meal. Dietary supplementation of 15% MLM improved rumen fermentation, growth performance, blood metabolites, plasma IGF-I and mitigated ammonia and methane without any adverse effects in growing buffalo calves.     

Effect of long term feeding of ammoniated wheat straw treated with or without HCl on blood biochemical parameters in growing male buffalo (Bubalus bubalis) calves

Twenty-four growing male buffalo calves (one year of age; 88.54 +/- 3.81 kg average body weight) were divided into three comparable groups (I, II and III) on the basis of their body weight (BW) in a completely randomised design to study the effect of long term feeding of ammoniated wheat straw (AWS) and hydrochloric acid treated ammoniated wheat straw (HCl-AWS) on blood biochemical changes. The animals were offered a concentrate mixture (CM) along with wheat straw (WS), ammoniated wheat straw (AWS) (4% urea at a 50% moisture level) and hydrochloric acid treated ammoniated wheat straw (HCI-AWS) (4% urea at a 50% moisture level and HCI added to trap 30% of NH3 evolved) in groups I, II and III, respectively for an average daily gain (ADG) of 500 g. All the diets were made iso-nitrogenous by preparing three types of concentrate mixtures of different CP levels. The blood was collected from the jugular vein randomly from three animals of each group initially after 8 months post feeding and subsequently after two months interval up to 14 months of experimental feeding. Due to urea ammoniation, the CP content of WS increased from 3.66 to 8.51 and was further increased to 11.35 due to the addition of HCl during urea-ammoniation of wheat straw. The cumulative period mean plasma glucose values (mg %), in group II (53.13) were significantly (P < 0.001) higher than those in groups I (48.44) and III (50.60). The cumulative period mean values of serum albumin and globulin (g %) were not significantly different and were comparable among the groups I (3.33 and 3.06), II (3.53 and 2.97) and III (3.49 and 2.94). The cumulative period mean values of serum albumin: globulin ratio and total protein values were not significantly different among the different groups. Serum urea and creatinine values were significantly (P < 0.001) higher in group III (58.66 and 2.24) as compared to groups I and II. The cumulative period mean values of serum alkaline phosphatase (ALP) (KA units) did not differ significantly, but serum glutamate pyruvate transaminase (SGPT) and glutamate oxaloacetate transaminase (SGOT) values (units x mL(-1) were significantly (P < 0.001) higher in groups II and III than in group I. The cumulative period mean values of T3 (ng x mL(-1)) did not differ significantly among the groups, but T4 values were significantly (P < 0.001) higher in group III (22.74) than in groups 1 (21.41) and II (20.89), respectively. Since the mean values of all the blood parameters were within the normal range, it may be concluded that feeding of ammoniated wheat straw treated with and without HCl to growing male buffalo calves for fourteen months has no adverse effect on the blood biochemical parameters.     

Rumen and post-rumen fermentation of spent tea leaf protein and other protein sources studied by the nylon bag method

Spent tea leaf (STL) and seven other protein feeds were subjected to microbial fermentation in nylon bags in the rumen of two fistulated buffalo calves and subsequent acid-pepsin digestion in vitro.The STL showed the lowest protein disappearance rate and rumen solubility at 8 h of fermentation. Polyphenols present in STL appear to offer protection to the protein and reduce rumen fermentation. An over-protection could be responsible for the low solubility of the protein in acid—pepsin solution.The high by-pass ability of STL protein appears to make it a suitable feed for growing calves and milking cows.     

Essential oils for dairy calves: effects on performance,scours, rumen fermentation and intestinal fauna

The first cause of death of dairy calves is often diarrhea which is mainly caused by pathogenic bacteria, which can result in excessive use of antibiotics. However, facing the increase concern by the industry and consumers, the use of antibiotics not only to control pathogens, but also to manipulate growth, has become a challenge. Alternative additives, such essential oils, have the potential to decrease antibiotic use, without reducing performance or increasing mortality of dairy calves. The objective of this study was to evaluate the use of a commercial blend of essential oils, incorporated into the calf starter and/or milk replacer to monitor the effect on overall calf performance, fecal scores and rumen fermentation parameters. A total of 30 Holstein calves received 6 l/day of a liquid diet, consisting of a commercial milk replacer containing 20% CP : 15% fat (EE). Calves had free choice access to water and calf starter. Weaning occurred at week 8, and calves were followed until the 10^th week of age. Calves were assigned to one of the three treatment groups in a randomized block design. Treatments: (1) control without essential oils supplementation (C); (2) essential oils blend in the milk replacer at 400 mg/kg (MR) and (3) essential oils blend in the milk replacer (200 mg/kg) and starter feed (200 mg/kg) (MRS). From the 2^nd week, calves were weighed and body measurements were taken, while concentrate intake and fecal scores were monitored daily. Blood samples were drawn weekly for determination of glucose and β-hydroxybutyrate. Fecal samples were collected weekly and analyzed for lactic acid bacteria and Enterobacteria; and ruminal fluid for determination of pH, short chain fatty acids, ammonia-N and counts of amylolytic and cellulolytic bacteria, and protozoa. Performance, fecal scores and intestines microorganisms were not affected by the essential oils supplementation. Ruminal and blood parameters were also not affected, with the exception the rumen ammonia-N concentration, with higher values when essential oils were supplemented in a combination of milk replacer and starter feed. Most of the evaluated parameters were affected by age of calves, mainly as a response to the increase in concentrate intake as animals’ aged. Essential oils are promising substitutes for antibiotics. However, the dose and routes of administration deserve further studies, allowing a better animal performance and health to be achieved.     

Effect of administration of anaerobic fungi isolated from cattle and wild blue bull (Boselaphus tragocamelus) on growth rate and fibre utilization in buffalo calves

Fifteen Murrah buffalo calves (age about 10 months, 163-176 kg BW) were divided into three groups. Group I (Control) was fed a complete feed mixture consisted of 50% wheat straw and 50% concentrate mixture (contained per kg: maize 330 g, groundnut cake 210 g, mustard cake 120 g, wheat bran 200 g, de-oiled rice bran 110 g, mineral mixture 20 g and common salt 10 g) along with 2 kg green oats per animal and day to meet the vitamin A requirements. Calves of Groups II and III were fed with the Control diet supplemented with Orpinomyces sp. C-14 and Piromyces sp. WNG-12 cultures, respectively. The digestibility of DM was significantly highest with Piromyces sp. WNG-12 in Group III (62.2%) followed by Orpinomyces sp. C-14 in Group II (60.3%), and Control (53.5%). A similar pattern of increase in digestibility of crude protein and cell-wall contents was observed in treatment groups. The digestible energy in terms of percent total digestible nutrients was also significantly enhanced in Groups II (56.6%) and III (59.9%) when compared to Control (49.2%). The rumen fermentation parameters such as pH and NH3-N were found to be lower, whereas total nitrogen, tricarboxylic acid precipitable-, nitrogen, total volatile fatty acids and zoospore counts per millilitre of rumen liquor were significantly higher in fungal administered groups. After administration of fungal cultures, improvements of animal growth rate (i.e. body weight gain) and feed efficiency were also observed.     

Effect of partial replacement of concentrates with jackfruit (Artocarpus heterophyllus) leaves on growth performance of kids grazing on native pasture of Tripura,India

Fifteen Black Bengal kids of about 3 months of age and body weight ranging from 3.8 to 4.9 kg were randomly distributed into three groups of five. Kids grazed native pasture 8 h/d. The kids in group I received supplementary concentrate (maize 35%, mustard cake 32%, rice bran 30%, mineral mixture 2% and common salt 1%) at approximately 2% of BW. However, 25 and 50% of the concentrate was replaced with jackfruit leaves for groups II and III, respectively. Total dry matter intake (DMI) was significantly higher in groups II and III than for group I due to greater forage consumption. Digestibility of CP (P < 0.05) decreased and that of NDF increased (P < 0.01) with increasing level of jackfruit leaves in the diet. Digestibility of ADF (P < 0.01), hemi cellulose (P < 0.05) and cellulose (P < 0.01) was higher in groups II and III in comparison to group I. Ruminal pH and TVFA concentration were not significantly different among the groups; however, rumen ammonia-N concentration decreased (P < 0.01) with increased level of jackfruit leaves in the diet. Similarly, plasma urea nitrogen and blood glucose levels were also reduced (P < 0.05) with increasing level of jackfruit leaves in the diet Average daily gain (ADG) was 47.33, 45.11 and 35.56 g/d in groups I, II and III, respectively. ADG and DMI/kg gain were not adversely affected when the level of replacement was restricted to 25%; however, at the 50% of replacement both parameters were adversely affected (P < 0.05). From the results of this experiment, it was concluded that jackfruit leaves might replace 25% of the supplemental concentrate for growing kids grazing in native pasture of northeast India.     

Performance of calves on diets containing Amaranthus leaf meal

Experiments were conducted to compare leaf meal of Amaranthus hy bridus sub-species hy bridus (Green Head) with lucerne meal and to study the effect of including up to 40% leaf meal of the same species of Amaranthus in calf rations. Fourteen concentrate diets calculated to be iso-caloric (75% TDN) and iso-nitrogenous (18% CP) were each given ad libitum to four Friesian calves from Day 11 to Day 56 post partum. Whole milk was also given at the rate of 4 l per calf per day. The first seven diets (Experiment I) contained 0, 5, 10 and 15% of either Amaranthus meal or lucerne meal. The rest (Experiment II) contained 0, 10, 20, 25, 30, 35 and 40% of Amaranthus leaf meal.Liveweight gains were similar on all the diets within each experiment and averaged about 0.5 and 0.4 kg/day in Experiments I and II, respectively. This was attributed to identical nutrient intake and efficiency of feed utilization. The relationship between oxalate intake, its disappearance in the gastro-intestinal tract of the experimental calves and apparent dietary calcium availability did not cause any appreciable differences in the performance of the experimental calves. Blood calcium levels of all the calves were within the normal range (9–12 mg/100 ml) during both trials.It is concluded that Amaranthus leaf meal is of comparable feeding value to lucerne meal in calf early weaner diets and that dairy calves perform well when given diets containing up to 40% leaf meal of Amaranthus.     

Effect of administration of anaerobic fungi isolated from cattle and wild blue bull ( Boselaphus tragocamelus ) on growth rate and fibre utilization in buffalo calves

Abstract

Fifteen Murrah buffalo calves (age about 10 months, 163 – 176 kg BW) were divided into three groups. Group I (Control) was fed a complete feed mixture consisted of 50% wheat straw and 50% concentrate mixture (contained per kg: maize 330 g, groundnut cake 210 g, mustard cake 120 g, wheat bran 200 g, de-oiled rice bran 110 g, mineral mixture 20 g and common salt 10 g) along with 2 kg green oats per animal and day to meet the vitamin A requirements. Calves of Groups II and III were fed with the Control diet supplemented with Orpinomyces sp. C-14 and Piromyces sp. WNG-12 cultures, respectively. The digestibility of DM was significantly highest with Piromyces sp. WNG-12 in Group III (62.2%) followed by Orpinomyces sp. C-14 in Group II (60.3%), and Control (53.5%). A similar pattern of increase in digestibility of crude protein and cell-wall contents was observed in treatment groups. The digestible energy in terms of percent total digestible nutrients was also significantly enhanced in Groups II (56.6%) and III (59.9%) when compared to Control (49.2%). The rumen fermentation parameters such as pH and NH₃-N were found to be lower, whereas total nitrogen, tricarboxylic acid precipitable-nitrogen, total volatile fatty acids and zoospore counts per millilitre of rumen liquor were significantly higher in fungal administered groups. After administration of fungal cultures, improvements of animal growth rate (i.e. body weight gain) and feed efficiency were also observed.     

Effects of isobutyrate supplementation in pre- and post-weaned dairy calves diet on growth performance,rumen development,blood metabolites and hormone secretion

Isobutyrate supplements could improve rumen development by increasing ruminal fermentation products, especially butyrate, and then promote the growth performance of calves. The objective of this study was to evaluate the effects of isobutyrate supplementation on growth performance, rumen development, blood metabolites and hormone secretion in pre- and post-weaned dairy calves. In total, 56 Chinese Holstein male calves with 30 days of age and 72.9±1.43 kg of BW, blocked by days of age and BW, were assigned to four groups in a randomized block design. The treatments were as follows: control, low-isobutyrate, moderate-isobutyrate and high-isobutyrate with 0, 0.03, 0.06 and 0.09 g isobutyrate/kg BW per calf per day, respectively. Supplemental isobutyrate was hand-mixed into milk of pre-weaned calves and the concentrate portion of post-weaned calves. The study consisted of 10 days of an adaptation period and a 50-day sampling period. Calves were weaned at 60 days of age. Seven calves were chosen from each treatment at random and slaughtered at 45 and 90 days of age. BW, dry matter (DM) intake and stomach weight were measured, samples of ruminal tissues and blood were determined. For pre- and post-weaned calves, DM intake and average daily gain increased linearly (P<0.05), but feed conversion ratio decreased linearly (P<0.05) with increasing isobutyrate supplementation. Total stomach weight and the ratio of rumen weight to total stomach weight tended to increase (P=0.073) for pre-weaned calves and increased linearly (P=0.021) for post-weaned calves, whereas the ratio of abomasum weight to total stomach weight was not affected for pre-weaned calves and decreased linearly (P<0.05) for post-weaned calves with increasing isobutyrate supplementation. Both length and width of rumen papillae tended to increase linearly for pre-weaned calves, but increased linearly (P<0.05) for post-weaned calves with increasing isobutyrate supplementation. The relative expression of messenger RNA for growth hormone (GH) receptor and 3-hydroxy-3-methylglutaryl-CoA synthase 1 in rumen mucosa increased linearly (P<0.05) for pre- and post-weaned calves with increasing isobutyrate supplementation. Blood concentrations of glucose, acetoacetate, β-hydroxybutyrate, GH and IGF-1 increased linearly (P<0.05) for pre- and post-weaned calves, whereas blood concentration of insulin decreased linearly with increasing isobutyrate supplementation. The present results indicated that isobutyrate promoted growth of calves by improving rumen development and its ketogenesis in a dose-dependent manner.     

Performance,rumen fermentation,blood minerals,leukocyte and antioxidant capacity of young Holstein calves receiving high-surface ZnO instead of common ZnO

ABSTRACT

This study was conducted to assess the effect of feeding high-surface ZnO instead of common ZnO on the performance, rumen fermentation, blood minerals, leukocytes and antioxidant capacity of pre- and post-weaning calves. Thirty male suckling Holstein calves were allotted to one of three experimental groups (10 replicates) in a completely randomised design. Calves received: (1) a low Zn diet without Zn supplementation (control diet), (2) a high Zn diet containing 50 mg supplementary Zn/kg dry matter (DM) as common ZnO or (3) a high Zn diet containing 50 mg supplementary Zn/kg DM as high-surface ZnO (nano-ZnO). The control diet contained a native Zn content of 35.5, 34.7 or 33.7 mg/kg DM for the age periods of 7 to 30, 31 to 70 and 71 to 100 d, respectively. Supplementation of the diet with Zn did not change the dry matter intake (DMI) of calves during d 7 to 30 but increased the ADG in this period (p < 0.05). During age periods of 31 to 70 and 71 to 100 d, DMI and ADG of the Zn supplemented calves were higher (p < 0.05) than the control animals. The nutrient digestibility and the concentration of rumen volatile fatty acids were positively affected (p < 0.05) and the rumen ammonia-N concentration decreased (p < 0.05) by dietary Zn supplementation. Furthermore, the incidence of diarrhoea and pneumonia was lower in calves receiving the Zn supplemented diets. Irrespective of ZnO source, the blood total antioxidant capacity, leukocyte and haematocrit levels significantly increased (p < 0.05) with the ZnO supplemented diets. The post-weaning DMI, nutrient digestibility and blood haematocrit levels were higher in calves receiving high-surface ZnO, compared to those supplemented with common ZnO. With inclusion of the Zn sources in pre- and post-weaning diets, the blood Zn concentration increased (p < 0.05), but the blood Cu, Fe, Ca, P and Mg levels remained unchanged. Regardless of source, dietary supplementation of young calves with ZnO improved the performance and decreased rumen ammonia-N and the incidence of diseases. Moreover, high-surface ZnO had advantages over common ZnO in increasing the post-weaning feed intake, digestibility and blood Zn concentration.     

Utilization of raw or heat-treated starch fed in liquid diet to pre-ruminants. 1. Calves.

Five 7-day-old Frisian bull calves, raised in Israel received twice a day a mixture of 40 g of soybean concentrate (65% protein) and 80 g of one of the following carbohydrates: glucose (G), expanded (heat-treated) (ES) or untreated (US) corn starch. In the afternoon the calves received in addition 400 g of milk replacer. Until weaning at experimental day 25, ES calves showed better growth and food utilization than their counterparts. Daily weight gain for the entire growing period up to slaughter was higher for the starch than for the glucose-fed group (P less than 0.05 for ES vs G). Heat treatment of starch increased its in vitro availability to amylase and its in vivo digestibility. Bypass of the rumen was complete in all G calves. In the ES and US groups, partial diversion of the liquid feed into the rumen was evident. The G group showed hyperglycemia after meals, while almost no increase in blood glucose level was observed after soy-starch meals (either US or ES).     

Influence of barley grain particle size and treatment with citric acid on digestibility,ruminal fermentation and microbial protein synthesis in Holstein calves

Chemical and physical treatments of barley grain increase ruminally resistant starch and can improve the rumen fermentation pattern. The objective of the present study was to evaluate the effects of chemical (addition of citric acid, CA) and physical (grinding to two different particle sizes, PS) treatment of barley grain on performance, rumen fermentation, microbial protein yield in the rumen and selected blood metabolites in growing calves. In all, 28 male Holstein calves (172±5.1 kg initial BW) were used in a complete randomised design with a factorial arrangement of 2 barley grain particle sizes×2 levels of citric acid. The diets were as follows: (i) small PS (average 1200 µm) barley grain soaked in water (no CA addition); (ii) small PS barley grain soaked in a CA solution (adding 20 g CA/kg barley); (iii) large PS (average 2400 µm) barley grain soaked in water (no citric acid addition) and (iv) large PS barley grain soaked in a citric acid solution (adding 20 g CA/kg barley). Barley grain was then incorporated at 35% in a total mixed ration and fed to the calves for 11 weeks. Feeding small PS barley decreased feed intake (P=0.02) and average daily weight gain (P=0.01). The addition of CA to barley grain did not affect intake but increased weight gain (P<0.01) and improved feed to gain ratio (P=0.03). Digestibility of organic matter and NDF tended (P<0.10) to increase, whereas faecal scoring was improved (P=0.03) and the presence of undigested grain particles in faeces was reduced (P<0.01) with CA-treated barley grain. Glucose and urea concentrations were increased (P<0.01) in the blood of calves fed the CA-treated barley grain. Ruminal pH tended (P=0.08) to be decreased with more finely ground barley and was increased when barley grain was treated with CA. Total volatile fatty acid concentrations in the rumen did not differ among treatments (P>0.05). However, the molar proportion of propionate was increased (P=0.03) when barley was more finely ground, and that of acetate was increased (P=0.04) when CA was added to barley grain. The ruminal concentration of ammonia nitrogen was increased (P<0.01) and microbial nitrogen synthesis in the rumen tended to decrease by adding CA to barley. Treating barley grain with citric acid increased fibre digestibility of total mixed rations, attenuated the decrease in ruminal pH, and improved weight gain and feed efficiency in male Holstein growing calves fed a high-cereal diet (550 g cereal grain/kg diet).     

Influence of weaning regimen on intake,growth characteristics and plasma blood metabolites in male buffalo calves

Experiment was conducted to evaluate the effect of weaning age on growth performance, feed intake, feed efficiency (FE) and blood metabolites in Nili-Ravi male buffalo (Bubalus bubalis) calves. Twenty-four male buffalo calves were assigned to one of the three treatment groups: continuous milk feeding (CMF), limited milk feeding (LMF) and early weaning (EW), and weaned off milk at 12, 10 and 8 weeks of age, respectively. For the first 3 days after birth, calves in all three treatments were fed colostrum, and were then moved to individual milk feeding at 10% of BW for the next 6 weeks. Thereafter, the provision of milk to the CMF group was gradually tapered to zero through week 12, using week 6 intakes as a base. The LMF calves were fed milk at 7.5%, 5.0%, 3.5%, and 1.5% of BW during weeks 7 to 10, respectively. Lastly, calves in the EW group were fed milk at 5.0% and 2.5% of BW at weeks 7 and 8, respectively. Calf starter (CS) feed was also provided ad libitum from weeks 2 to 12 and individual intakes were recorded on a daily basis. Blood samples were taken from weeks 6 to 12, on a weekly basis; whereas, the BW, heart girth, withers height and hip width were measured at the start of experiment and later on a weekly basis. Weight gain, average daily gain, and body measurements were the same across all three groups. Milk intake was lower (P < 0.05), whereas CS intake was greater (P < 0.05) in the EW calves compared with the other treatment groups. Dry matter intake was greater (P < 0.05) in the EW and LMF calves compared with the CMF calves. The FE was greater (P < 0.05) in the CMF calves compared with the LMF and EW treatment groups. Blood glucose concentration was similar among the treatments; however, blood urea nitrogen was greater (P < 0.05) in the EW calves compared with the CMF and LMF groups. Plasma concentration of non-esterified fatty acids was higher (P < 0.05) in the EW calves compared with the CMF calves. In light of these results, it is evident that buffalo calves can be successfully weaned as early as 8 weeks of age without negatively affecting their growth performance.     

Influence of fumaric acid on ruminal parameters and organ weights of growing bulls fed with grass or maize silage

The influence of the potential methane reducer, fumaric acid (FA), on ruminal parameters, the rumen wall and organ weights was investigated in a long-term study with growing bulls. In all, 20 bulls were fed with maize or grass silage as roughage, and with concentrate with or without 300 g FA per animal and day during the whole fattening period. After slaughtering, the organs were weighed and blood serum was analysed for glucose, β-hydroxybutyric acid (BHB) and non-esterified fatty acid concentration. The ruminal fluid was analysed for short-chain fatty acids, ammonia-N and the microbial community via single strand conformation polymorphism analysis. The rumen wall was examined histopathologically and results were graded as ‘no visible lesions’, ‘few inflammatory infiltrates’, ‘some inflammatory infiltrates’ or ‘several inflammatory infiltrates’. In addition, the dimensions of the rumen villi were measured. The FA supplementation decreased the serum BHB concentration and the butyric acid concentration in the ruminal fluid. The microbial community in the ruminal fluid was not influenced by FA. An interaction between FA and silage type was observed for the inflammation centres counted in the villous area of rumen papillae. This interaction was also observed in the length and surface of the rumen villi. Rumen villi results show that the influence of FA depends on the roughage used in the diet.     

Total mixed ration pellets for light fattening lambs: effects on animal health

Fifty male Merino lambs (6 to 8 weeks, 14.1 kg; n=10 per group) were used to study the effect of feeding system: barley straw in long form and concentrate pellets in separate troughs (Control), ad libitum alfalfa supplemented with concentrate in separate troughs (Alfalfa) or including various levels of ground barley straw in concentrate pellets (B05, B15 and B25 for 50, 150 and 250 g barley straw/kg), on rumen characteristics, acid-base status, blood cell counts and lymphocyte stimulation. Alfalfa lambs had the heaviest digestive tract contents, highest rumen pH values, lowest volatile fatty acid concentration, highest papillae counts and best mucosa colour and the greatest blood pCO₂ values, lowest sodium and chloride and highest potassium concentrations (P<0.05). Including ground barley straw in the concentrate pellet or providing straw in long form separately from the concentrate reduces rumen pH and darkens ruminal mucosa as compared with alfalfa-fed lambs, thus affecting acid-base status.     

Calcium propionate supplementation improves development of rumen epithelium in calves via stimulating G protein-coupled receptors

In the present study, calcium propionate (CaP) was used as feed additive in the diet of calves to investigate their effects on rumen fermentation and the development of rumen epithelium in calves. To elucidate the mechanism in which CaP improves development of calf rumen epithelium via stimulating the messenger RNA (mRNA) expression of G protein-coupled receptors, a total of 54 male Jersey calves (age=7±1 days, BW=23.1±1.2 kg) were randomly divided into three treatment groups: control without CaP supplementation (Con), 5% CaP supplementation (5% CaP) and 10% CaP supplementation (10% CaP). The experiment lasted 160 days and was divided into three feeding stages: Stage 1 (days 0 to 30), Stage 2 (days 31 to 90) and Stage 3 (days 91 to 160). Calcium propionate supplementation percentages were calculated on a dry matter basis. In total, six calves from each group were randomly selected and slaughtered on days 30, 90 and 160 at the conclusion of each experimental feeding stage. Rumen fermentation was improved with increasing concentration of CaP supplementation in calves through the first 30 days (Stage 1). No effects of CaP supplementation were observed on rumen fermentation in calves during Stage 2 (days 31 to 90). Supplementation with 5% CaP increased propionate concentration, but not acetate and butyrate in calves during Stage 3 (days 91 to 160). The rumen papillae length of calves in the 5% CaP supplementation group was greater than that of Con groups in calves after 160 days feeding. The mRNA expression of G protein-coupled receptor 41 (GPR41) and GPR43 supplemented with 5% CaP were greater than the control group and 10% CaP group in feeding 160 days calves. 5% CaP supplementation increased the mRNA expression of cyclin D1, whereas did not increase the mRNA expression of cyclin-dependent kinase 4 compared with the control group in feeding 160-day calves. These results indicate that propionate may act as a signaling molecule to improve rumen epithelium development through stimulating mRNA expression of GPR41 and GPR43.     

Effects of replacing soybean meal with pumpkin seed cake and dried distillers grains with solubles on milk performance and antioxidant functions in dairy cows

Pumpkin seed cake (PSC), a byproduct of pumpkin seed oil processing, is used in ruminant feed as a beneficial protein source. Experiments were conducted to evaluate PSC as a substitute for soybean meal in the diets of lactating cows based on performance, rumen fermentation, antioxidant function and nitrogen partitioning. Six multiparous lactating cows were used in a replicated 3 × 3 Latin square experiment with 27-day periods. The cows were randomly divided into three treatment groups: group (1) was fed a diet containing no PSC (0PSC), and groups (2) and (3) were fed diets in which soybean meal was replaced with PSC and dried distillers grains with solubles (DDGS) at levels of 50% (50PSC) and 100% (100PSC), respectively. The diets were isonitrogenous and contained identical roughage but different proportions of PSC and DDGS. Replacement of soybean meal with PSC and DDGS did not influence rumen degradation, milk performance, rumen fermentation, DM intake or apparent total tract digestibility, and nitrogen partitioning between milk, feces and urine did not differ in the animals fed the three diets. However, compared with a diet containing no PSC, the total antioxidant capacity (P < 0.05) and antioxidant enzymes (total superoxide dismutase, glutathione peroxidase and catalase) activities (P < 0.05) were increased in the animals that received the 50PSC and 100PSC diets. In contrast, addition of PSC significantly reduced concentrations of aspartate transaminase (P < 0.05), alkaline phosphatase (P < 0.05) and malondialdehyde (P < 0.05) in the plasma. These results demonstrate that PSC can be completely substituted for soybean meal in the diet of dairy cows without any negative impact on milk performance, rumen fermentation or apparent digestibility and that this dietary change improves antioxidant functions and blood parameters in dairy cows, indicating that PSC has the potential for use as a feed source for dairy cows.     

Successful culmination of pregnancy and live birth following the transfer of frozen-thawed buffalo embryos

A total of 141 embryos was recovered by nonsurgical flushing of the uterus of 31 superovulated buffalo. A total of 66 good quality embryos (Grade I and Grade II) was frozen using 1.4 M glycerol. Forty-two of the frozen embryos were thawed randomly over a 1-year period, and a total of 39 embryos (Grades I, II or III post thaw) were transferred into an equal number of estrus synchronized recipients. Of 11 confirmed pregnancies, 9 calves were born live.     

The digestion in the small intestine of young bulls of the protein of rapeseed meal treated or untreated with formaldehyde

Twelve bulls of approximately 140 kg bodyweight were each fitted with simple cannulae in the rumen and abomasum and a re-entrant cannula in the terminal ileum. They were kept in individual pens and given daily 1.8 kg of a basal diet containing dried maize meal (whole plant), dried sugarbeet pulp and a urea/mineral preparation in the proportions 0.80, 0.18 and 0.02. Four animals received this diet alone, four received in addition 198 g daily (11 g N) of rapeseed meal by infusion into the abomasum and the remaining four the basal diet plus the same amount of formaldehyde-treated rapeseed also by infusion.The concentration of ammonia-N in the rumen fluid of animals given the untreated rapeseed meal was higher (P < 0.05) than for those on the other two treatments. The pH of the rumen and abomasal fluid was similar on all treatments. Coefficients for the apparent disappearance in the small intestine of the dry matter and nitrogen of untreated rapeseed meal infused into the abomasum were 0.76 and 0.75, respectively. In contrast formaldehyde-treated rapeseed meal was poorly digested. It is suggested that procedures for the treatment of rapeseed meal that will minimise the degradability of its protein in the rumen, yet prevent depression of its digestion and absorption in the abomasum and small intestine have still to be defined.     

Response of goats to partial replacement of dietary protein by a leaf meal mixture containing Leucaena leucocephala,Morus alba and Tectona grandis

This study investigated the effects of Leucaena leucocephala–Morus alba–Tectona grandis (2:1:1) based leaf meal mixture as a protein supplement to partially (50%) replace conventional supplements on the performance of female goats. Local female goats (12) were divided into three groups in a completely randomized design to receive either a leaf meal mixture (LMTM) based supplement, or groundnut cake (GNC) or soybean meal (SBM) incorporated concentrate, and wheat straw as basal diet for a period of about 4 months. Blood enzymes and immunological profile were monitored in all goats at 0, 30, 60 and 90 days of feeding. While dry matter intake (DMI) (g kg^−0.75 BW) of goats given LMTM was higher (P<0.05) than SBM, it was comparable to their counterparts fed GNC. Digestibility of nutrients, except for depressed crude protein digestibility (P<0.05) in SBM group, was comparable among dietary treatments. Nitrogen intake and fecal excretions were similar irrespective of supplements, the urinary excretion of N in goats given GNC was significantly higher than comparable excretion in goats on LMTM and SBM. Balance of N (g per day) remained positive in all goats, however it was significantly higher in animals on LMTM as compared to GNC. The DCP, TDN and ME values of the composite diets were comparable among dietary treatments. Intake of DCP, TDN and ME was close to stipulated NRC requirements. Blood enzymes (alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) and serum protein electrophoresis pattern (albumin, α-globulin, β-globulin and γ-globulin) did not differ significantly due to the replacement of 50% dietary protein by LMTM throughout the experiment. It may be concluded that leaf meal mixture could be used inexpensively as a vegetable protein supplement to wheat straw based diets for goats without any adverse effect on voluntary intake, nutrient utilization, serum enzymes and immune status.