RESUMO
Objectives of the present study were to evaluate the effects of supplementation of bypass fat on milk production and reproductive performance of crossbred cows. Nineteen multiparous crossbred cows (2-4 lactation) were divided in two groups on the basis of most probable production ability (MPPA). The animals in group 1 (nine cows, MPPA 3,441.32 kg, control group G1) were fed chaffed wheat straw, chopped green maize, and concentrate mixture as per requirements while the animals in group 2 (10 cows, MPPA 3,457.2 kg, treatment group G2) were fed the same ration supplemented with 2.5% bypass fat (on DMI basis). The cows of G2 were supplemented bypass fat 40 days prepartum to 90 days postpartum and carry over effect of supplementation on milk production and reproductive parameters was monitored up to 210 days of lactation. Average birth weights of the calves were 24.94 and 27.95 kg in G1 and G2, respectively. The calving per cent in G1 (88.88%) was lower than that of G2 (100%). The time taken for expulsion of fetal membranes was decreased (P<0.05) by 5.4 h in G2 compared to G1. Days required for involution of uterus was less (P<0.05) in G2 (35.40 days) than that of G1 (49.44 days). Less number of cases of retention of fetal membranes (RFM) and metritis were observed in G2 as compared to that of G1. The average milk yield (210 days) in G2 was higher (P<0.05) than that of G1 (18.65 vs 17.57 kg/day). Similarly, the milk yield during the carry over period (90 days) was higher (P<0.05) in G2 than that of G1 (14.81 vs 13.79 kg/day). The time required for onset of cyclicity was reduced (P<0.05) by 6.5 days in G2 as compared to that of G1. The service period and AI per conception were also reduced (P<0.05) in G2 while bypass fat feeding showed no effect on conception rate (P<0.80). There were no differences between the two groups in plasma cholesterol, progesterone and insulin concentrations. Hence, it was concluded that bypass fat supplementation at 2.5% of DMI increased the milk production and reduced the time required for involution of uterus and commencement of cyclicity. AI per conception, incidences of metritis and RFM were also reduced on supplementing bypass fat.
Assuntos
Ração Animal/análise , Bovinos/crescimento & desenvolvimento , Indústria de Laticínios/métodos , Gorduras na Dieta/farmacologia , Suplementos Nutricionais , Leite/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Animais , Cruzamento/métodos , Colesterol/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Índia , TemperaturaRESUMO
The present study was conducted to evaluate the effect of commercial exogenous fibrolytic enzyme (EFE) mixture added at 1.5 and 3.0 g (cellulase 4,000 microM glucose/g/h + xylanase 7,990 microM xylose/g/min; 50:50 w/w) per kilogram of dry matter (DM) of feed on nutrient digestibility, milk production, milk composition, and some blood constituents in lactating Murrah buffaloes. Eighteen buffaloes were allotted to three dietary treatments, on the basis of milk yield (8.48, 8.52, and 8.53 kg/day) and days in lactation (68.5, 80.33, and 82.00) for 90 days. The buffaloes were fed a total mixed ration (TMR) comprising of 45% chaffed wheat straw, 15% chopped green maize, and 40% concentrate on DM basis (control group), the same TMR plus EFE at 1.5 g/kg DM (T-1 group) and the same TMR plus EFE at 3.0 g/kg DM (T-2 group) supplemented through the concentrate mixture. There was no effect of fortifying EFE mixture on DM intake and crude protein intake (grams per day) whereas total digestible nutrients intake (kilogram per day) was higher by (P < 0.05) 12.53% in T-1 group over that of control, and there was no significant difference between T-2 and control groups. The average daily milk yield and 4% fat-corrected milk (FCM) yield was higher (P < 0.05) by 12.99% and 15.17% in T-1 group as over that of control, and there was no difference between T-2 and control groups. There was no (P > 0.05) difference in blood glucose and blood urea nitrogen concentration in different experimental groups. It is concluded that supplementation of cellulase and xylanase mixture at 1.5 g/kg of DM of TMR containing wheat straw (45%), green maize (15%), and concentrate (40%) on DM basis significantly increased (P < 0.05) the average daily milk yield and FCM yield in Murrah buffaloes due to improved dietary fiber digestion.