Impact of Dietary Phytogenic Composite Feed Additives on Immune Response, Antioxidant Status, Methane Production, Growth Performance and Nutrient Utilization of Buffalo (Bubalus bubalis) Calves.

The focus on the bioactive effects of plants concerns mainly ruminal microflora for the modulation of rumen fermentation with very little emphasis placed on their consequences on health parameters, including antioxidative and immune stimulating effects. The aim of the present study was to examine the effects of supplementing phytogenic feed additives composed of a mixture of eucalyptus (Eucalyptus citriodora) and poplar (Populus deltoides) leaf-meal (EPLM) on immune response, antioxidant status, metabolic profile, enteric methane production, growth performance, and nutrient utilization in buffalo (Bubalus bubalis) calves. In vitro studies with graded doses of EPLM extract revealed a reduction in total gas and methane production with an increased proportion of propionate without affecting feed degradability. In the in vivo experimentation, eighteen female buffalo calves (10-14 months old, avg. body weight 131.68 ± 7.50 kg) were divided into three groups (CONT, EPLM-1, and EPLM-2) of six each in a completely randomized design. Treatment groups were supplemented with a blend (1:1) of dry grounded eucalyptus (Eucalyptus citriodora) and poplar (Populus deltoids) leaves (50 g, EPLM-1; 150 g, EPLM-2). Feed intake and growth rate of buffalo calves fed on different feeding regimens did not differ (p > 0.05). Haemato-biochemical parameters reveal no variations (p > 0.05) among groups, irrespective of period of collection, except the concentration of blood urea, which was decreased (p < 0.05) in both treatment groups as compared to the control. The levels of reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) increased (p < 0.05) in EPLM supplemented animals as compared to CONT. The extent of lipid peroxidation (LPO) was reduced (p < 0.05) with increased level of EPLM in the diet. The total thiol group (T-SH) was also increased with the supplementation of leaves in the diet. The mean absolute values for skin thickness following the intra-dermal injection of PHA-P were increased (p < 0.05) in all the supplemented animals relative to CONT. However, there was no significant difference among the calves fed graded levels of these feed additives in the diet. The Ab titer against Pasteurella multocida vaccine was higher (p < 0.05) on both day 45 and 90 in both treatments, irrespective of the level of additive supplemented. The enteric methane production was reduced in EPLM supplemented buffaloes; however, digestibility of all the nutrients remained comparable (p > 0.05) among the animals. It may be concluded that blends of eucalyptus (Eucalyptus citriodora) and poplar (Populus deltoides) leaf-meal (50 g/h/d) containing 3.19 g, 2.30 g, and 0.71 g of total phenolics, tannin phenolics, and condensed tannins, respectively, can be used as the phytogenic feed additive for improving antioxidant status and immunity of buffalo calves, and mitigating enteric methane production without affecting performance and nutrient utilization.

Reducing Ruminal Ammonia Production With Improvement in Feed Utilization Efficiency and Performance of Murrah Buffalo (Bubalus bubalis) Through Dietary Supplementation of Plant-Based Feed Additive Blend.

The study evaluated the potential of blends of eucalyptus oil and aqueous extract of mulethi (root of Glycyrrhiza glabra) to reduce rate of ruminal ammonia production without affecting feed digestion to improve nitrogen utilization efficiency and performance of Murrah buffalo (Bubalus bubalis). Based on preliminary independent studies with graded doses of eucalyptus oil and mulethi root aqueous extract in modulating in vitro rumen fermentation, four blends of feed additive comprising graded doses (5, 10, 15, and 25 µL) of eucalyptus oil and a fixed quantity (15 µL) of aqueous extract of mulethi roots were prepared and examined for their effects on in vitro rumen fermentation and on methane and gas production in 100-mL calibrated glass syringes by standard IVGP protocol. Rumen liquor was collected from four rumen fistulated Murrah buffaloes fed a total mixed ration. Out of four blends, blend-1 comprising 5 µL of eucalyptus oil and 15 µL of aqueous extract (233.6 g/L DW) of mulethi per 40 mL of in vitro medium was found to reduce ammonia production significantly (p < 0.001) without affecting feed digestibility. An equivalent dose of blend-1 (10.5 mL of eucalyptus oil and 7.35 g of mulethi root powder/h/day) fed to four rumen fistulated buffaloes for 24 days resulted in 50% reduction (p < 0.05) in rumen ammonia level with no inhibition in feed fermentation or short-chain fatty acid production. The total bacterial population including Ruminococcus albus, Fibrobacter succinogenes, Butyrivibrio fibrisolvens, and Megasphaera elsdenii as well as anaerobic fungi and methanogenic archaea remained unaffected (p > 0.05). Twelve buffalo calves (avg. BW 137.5 ± 9.2 kg, 8-12 months old) divided into two groups of six each and fed a total mixed ration (concentrate: roughage; 60:40) with or without supplementation of blend-1 for about 3 months demonstrated 14% increase (p < 0.05) in average daily gain in BW with a trend (p < 0.10) in improvement of feed or protein utilization efficiency (1.4 vs. 1.1 g crude protein/g average daily gain; 21.4% increase). Thus, supplementation of eucalyptus oil-mulethi root blend could reduce ruminal ammonia production and improve feed utilization efficiency in ruminants.

Abatement of enteric methane production from lactating Murrah buffaloes (Bubalus bubalis) with improving production performance and immune status through dietary supplementation of composite feed additive.

Ruminant livestock production processes are the major sources of methane production in agriculture sector triggering global environmental pollution. Above 90% of world buffalo population present in Asian countries, India ranks first and contributes significantly to the environmental pollution by enteric methane emissions. In this study, we examined the effect of dietary composite feed additive supplementation on ruminal methane production, nutrient utilization, milk production and immune status of buffaloes (Bubalus bubalis). Eighteen lactating Murrah (Bubalus bubalis) buffaloes at early stage of lactation were divided into two groups of nine animals and fed a composite feed additive [consisted of (%, w/w) dried and ground leaves of Cordia dichotoma and Holoptelea integrifolia, 31.4 each; garlic oil, 0.6; sodium nitrate, 3.1; magnesium sulphate, 8.4; mustard oil, 12.6 and cottonseed oil, 12.5] which contained an ideal combinations of methane inhibitors, alternate hydrogen sinks and rumen stimulating agents to treatment (CFA) group animals along with basal feed of chaffed green sorghum (Sorghum bicolor) fodder, chaffed wheat straw and concentrate mixture for maintenance and milk production. The results showed a decrease (44.6%) in methane concentration in exhaled air of CFA group buffaloes with increase (p < 0.05) in digestibility of feed in comparison to control (CON). Total digestible nutrient (TDN) content of the ration fed to buffaloes of CFA group was significantly (p < 0.05) increased. The daily milk yield, 6% fat corrected milk (FCM) yield and immune response were also increased (p < 0.05) in CFA group. The study suggests that the supplementation of composite feed additive was effective to reduce enteric methane emissions and improvement in production performance and immune status of buffaloes.

Sources and Levels of Trace Elements Influence Some Blood Parameters in Murrah Buffalo (Bubalus bubalis) Calves.

Sources of supplemental minerals in the diet of animals are of important significance. Bio-availability of organic sources is believed to be more in the body as compared to regularly used inorganic sources and hence environment-friendly due to reduced mineral excretion, which in turn reduces their requirements in the diet as well. Twenty-four male Murrah buffalo (Bubalus bubalis) calves (about 18-20 months of age and 318.54 ± 8.85 kg body weight) were divided randomly into four groups of six animals each. In the control group (C, InOrg100) zinc (Zn), copper (Cu), and manganese (Mn) were supplemented through an inorganic source, while in treatment groups, organic source at the rate of 50, 75, or 100% (in groups T1 (Org50), T2 (Org75), and T3 (Org100), respectively) was fed at level as supplemented in the control group. Feeding was continued for a period of 180 days with blood sampling at day 0 followed by a regular interval of 45 days. Plasma samples were analyzed for trace elements Cu, Mn, Zn, and iron (Fe), total antioxidant status, ceruloplasmin, and superoxide dismutase (SOD) with cell-mediated and humoral immune response. Plasma levels of different trace minerals like Fe, Mn, and Cu remained unaffected with two sources and different levels of organic minerals, except the level of Zn, which showed higher (P < 0.05) levels in the group Org100 compared to others, and remained indicative of higher bio-availability through the organic source. The concentration of plasma total antioxidants indicated no adverse effect on the reduction of supplemental levels up to half of these minerals. Also, the level of plasma SOD was high (P < 0.05) at each level of the organic source as compared to the 100% level of the inorganic source. Immune response in respect of cell-mediated as well as humoral immunity did not show any reduction in different groups. The study indicated beneficial impacts of the organic source in the form of superior plasma Zn level as well as SOD concentrations. In addition, no negative effect on most of the studied parameters was observed after reducing supplemental trace minerals to half indicating higher bio-availability of organic trace minerals.