Effect of feeding calcium propionate supplemented cotton seed cake on milk yield, milk composition and aflatoxin concentration in lactating buffaloes.

The objective of the current study was to reduce aflatoxin in a cotton seed cake (csc)-based diet and to decrease M1 level in milk by treating it with increasing levels of calcium propionate. Sixteen multiparous Nili-Ravi buffaloes were allocated to one of four treatments in a replicated 4 × 4 Latin square design. The treatments were calcium propionate treatment on csc at 0, 0.25, 0.50 and 0.75%. The duration of each period was 20 days. The level of aflatoxin was 100 ug/kg aflatoxin B1 (AFB1) in the control diet. Calcium propionate application decreased the concentration of aflatoxin M1, and the treatments were 1.63, 0.83, 0.29 and 0.44 ug/kg in 0.25, 0.50 and 0.75%, respectively. Milk yield and milk composition were not affected across the whole range of treatment. In conclusion, oral intake of calcium propionate reduced the AF transfer from feed to milk without changing milk yield and composition.

Nitrogen balance, production performance, and plasma metabolites of lactating buffaloes in response to varying dietary protein levels.

Protein imbalance in dairy rations affects N balance and milk N efficiency (MNE) resulting in extra N excretion to the environment. The objective of this study was to investigate the changes in N balance, milk production, and plasma metabolites of lactating buffaloes in response to different dietary crude protein (CP) supplies. Six multiparous Nili Ravi buffaloes in mid-lactation were used in this experiment in a 3 × 3 Latin square design. The treatments were diets with 9.26, 10.0, and 11.4% of CP on DM basis. All the diets were iso-caloric (2.05 Mcal metabolizable energy/kg of DM), whereas oat silage was mixed with the respective concentrate and offered once daily as total mixed ration. Milk fat content and yields of actual milk, 4% fat corrected milk, milk fat, protein, and lactose increased by 3.97, 9.63, 11.8, 6.23, and 6.57%, respectively. Milk protein content tended to increase linearly with increasing dietary CP levels. Milk N secreted as g/d increased, while as percent of N intake decreased. The resulting decrease in MNE (13.7%) was 3.45 greater than the increase in milk yield observed by increasing dietary CP from 9.26 to 11.4% of DM. Total manure N increased linearly in terms of g/d and tended to increase as percent of N excreted. Excretion rate of N also increased linearly by 32%. In conclusion, milk yield, milk fat, protein, and lactose yields increased; however, decreased MNE indicates relatively greater N losses as observed by increased N excretion rate when CP level increased from 9.26 to 11.4% in the diet of lactating buffaloes.

Effect of increasing pre-pubertal concentrate levels on reproductive and lactation performance of Nili-Ravi Buffalo heifers.

The objective of this study was to determine the effect of increasing total nutrient supply by increasing level of concentrate supplementation in forage-based diet of growing Nili-Ravi buffalo replacement heifers on pre-pubertal growth rate and its impact on age at puberty and post-pubertal productive and reproductive performance. Twenty-eight Nili-Ravi buffalo heifers of 7 ± 1 month age were divided into 3 groups. The treatments were 3 levels of concentrate (crude protein (CP) = 17.9%, metabolisable energy (ME) = 2.66 Mcal/kg), i.e. 0.5, 1, and 1.5% of the body weight referred as low, medium, and high treatments, respectively. Irrespective of pre-pubertal treatment, all the heifers received similar feed after puberty up to completion of their first lactation. The results of the study showed a similar response across the treatments in age, weight, and condition at puberty, weight at calving, lactation length, and yield. The medium and high treatments resulted in poor reproductive performance because of higher services per conception and less number of heifers confirmed conceived compared with low treatment. The low treatment resulted in less mortality compared with medium and high treatments. The feeding cost per animal at puberty, conception, and calving was lowest for treatment low as compared with medium and high. In conclusion, the results of the study showed that Nili-Ravi buffalo heifers achieved puberty at 23 months with feeding of concentrate (CP = 17.9%, ME = 2.66 Mcal/kg) during pre-pubertal stage at the rate of 0.5% of the body weight with better reproductive performance.

Effects of increasing dietary protein supplies on milk yield, milk composition, and nitrogen use efficiency in lactating buffalo.

Nitrogen efficiency of lactating buffalo can be increased by providing dietary crude protein (CP) precisely to the requirement. Twelve lactating Nili-Ravi buffaloes (6 primiparous and 6 multiparous) at 76 ± 37.5 days in milk (DIM) were used in this study. The treatments were diets providing three levels of CP (% DM basis): (1) low-protein = 11%; (2) medium-protein = 13.1%; (3) high-protein = 14.2% according to a 3 × 3 Latin square design. The period length of each treatment was 21 days and the total duration of experiment was 63 days. The diets were designed to provide similar energy. The nitrogen intake of buffalo increased linearly by increasing CP levels. Dry matter intake showed a tendency toward decrease in quadratic fashion, whereas milk yield decreased linearly in high-protein diet. No effect was observed on milk protein yield and content. Increasing the dietary CP levels increased plasma urea nitrogen, whereas glucose and triacylglycerol levels remain unaffected. Efficiency of dietary nitrogen utilization to milk averaged 21% and showed both linear and quadratic decreases by increasing the protein supply levels. In conclusion, low CP level showed higher milk production with low plasma urea nitrogen and high nitrogen efficiency in this experiment.

Effect of increasing dietary metabolizable protein on nitrogen efficiency in Holstein dairy cows.

OBJECTIVE: The objective of the study was to determine the effects of increasing levels of metabolizable protein (MP) on lactation performance and nitrogen (N) efficiencies in lactating dairy cows. METHODS: Nine multiparous cows in mid lactation [113±25 days in milk] received three treatments in a 3×3 Latin square design with a period length of 21 days. The treatments were three diets, designed to provide similar energy and increasing supply of MP (g/d) (2,371 [low], 2,561 [medium], and 2,711 [high] with corresponding crude protein levels [%]) 15.2, 18.4, and 20.9, respectively. RESULTS: Increasing MP supplies did not modify dry matter intake, however, it increased milk protein, fat, and lactose yield linearly. Similarly, fat corrected milk increased linearly (9.3%) due to an increase in both milk yield (5.2%) and milk fat content (7.8%). No effects were observed on milk protein and lactose contents across the treatments. Milk nitrogen efficiency (MNE) decreased from 0.26 to 0.20; whereas, the metabolic efficiency of MP decreased from 0.70 to 0.60 in low to high MP supplies, respectively. The concentration of blood urea nitrogen (BUN) increased linearly in response to increasing MP supplies. CONCLUSION: Increasing MP supplies resulted in increased milk protein yield; however, a higher BUN and low MNE indicated an efficient utilization of dietary protein at low MP supplies.

Effect of once-a-day milk feeding on behavior and growth performance of pre-weaning calves.

OBJECTIVE: The objectives of the present study were to evaluate the effects of once-a-day milk feeding on growth performance and routine behavior of preweaning dairy calves. METHODS: At 22nd day of age, twenty-four Holstein calves were randomly assigned to one of two treatment groups (n = 12/treatment) based on milk feeding frequency (MF): i) 3 L of milk feeding two times a day; ii) 6 L of milk feeding once a day. The milk feeding amount was reduced to half for all calves between 56 and 60 days of age and weaning was done at 60 days of age. To determine the increase in weight and structural measurements, each calf was weighed and measured at 3 weeks of age and then at weaning. The daily behavioral activity of each calf was assessed from the 22nd day of age till weaning (60th day of age) through Nederlandsche Apparatenfabriek (NEDAP) software providing real-time data through a logger fitted on the calf's foot. RESULTS: There was no interaction (p≥0.17) between MF and sex of the calves for routine behavioral parameters, body weight and structural measurements. Similarly, there was no effect of MF on routine behavioral parameters, body weight and structural measurements. However, the sex of the calves affected body weight gain in calves. Male calves had 27% greater total body weight and average daily gain than female calves. There was no effect of the sex of the calves on behavioral measurements. Collectively, in the current study, no negative effects of a once-a-day milk feeding regimen were found on routine behavioral and growth parameters of preweaning calves in group housing. CONCLUSION: Once-a-day milk feeding can be safely adopted in preweaning calves from 22nd day of age.

Effects of peripartal glucose precursor supplementation on lactation performance and metabolic health of primiparous and multiparous dairy cows.

OBJECTIVE: Hyperketonemia remains a major metabolic issue of serious milk production and a major health concern in early lactation cows. Oral supplementation of glucose precursors (GP) can be used to prevent hyperketonemia in dairy cows. The objective of this study was to compare the beneficial effects of orally supplementing a mixture of GP on metabolic health indicators and milk production status of primiparous (PP) and multiparous (MP) dairy cows. METHODS: Twenty-eight Holstein cows were blocked by expected date of parturition, previous lactation yield, and parity. The cows were randomly allocated to one of the four treatment groups (n = 7 cows/group) based on their parity and GP supplementation: i) PP cows fed basal diet only (PP-CON), ii) PP cows with oral supplementation of GP (PP-GP), iii) MP cows fed basal diet only (MP-CON), and iv) MP cows with oral supplementation of GP (MP-GP). Glucose precursor (glycoline liquid) was orally drenched (300 mL/d) in GP cows from 7 days prepartum through 7 days postpartum. Other than GP supplementation, all cows were fed similar pre- and postpartum basal diets. RESULTS: In both pre- and postpartum periods, serum glucose concentration was increased, whereas ß-hydroxybutyrate and free fatty acids were decreased in GP cows compared with the CON cows. Milk yield and milk components were statistically not different between GP and CON cows over the first 9 week of lactation. The yield of actual milk, energy-corrected milk, 63-days cumulative milk, colostrum yield, and calf birth weight remained higher in MP cows compared with PP cows. CONCLUSION: Oral drenching of GP around calving can be recommended to successfully improve the metabolic health and reduce the negative effects of hyperketonemia not only in MP but also in PP dairy cows.

Effect of photoperiodicity and methods of follicular wave emergence on follicle turn-over, recovery and quality of oocytes, and early in-vitro developmental competence of embryos using ovum pick-up in Nili-Ravi buffaloes: Preliminary evidence.

The objectives of the present study were to evaluate the effects of photoperiodicity, gauge (G) of ovum pick-up (OPU) needle, and two methods of follicular wave emergence on follicular turn-over, oocyte recovery (OR), quality of the oocytes (OQ), and early in-vitro developmental competence of embryos in Nili-Ravi buffaloes (n = 20). In 1st experiment, buffaloes (n = 12; 4 buffaloes/season) were randomly assigned to optimize the OPU's (n) either with 17 G or 18 G needle in one of the following seasons: 1) peak breeding season (PBS; Sep-Nov; n = 31), 2) transition breeding season (TBS; Dec-Feb; n = 32), and 3) low breeding season (LBS; Apr-June; n = 32). During 2nd experiment, buffaloes (n = 8) were enrolled randomly in a 2 × 2 cross-over design to compare the two methods of wave emergence either using follicular ablation (FA; n = 4), or synchronization protocol (CIDR-EB; n = 4) during PBS. In FA method, the ovarian follicles were aspirated (week -1), and subsequently repeated OPU's (n = 55) were performed for 7 weeks. However, in CIDR-EB synchronized buffaloes, a progesterone device (CIDR) was inserted in the anterior vagina and a single dose of estradiol benzoate (2 mg) and prostaglandin (150 µg) were administered i.m. on d 1. The CIDR was removed on d 7 and repeated OPU's (n = 56) were performed. In both experiments, a 7-d resting period was provided between each OPU session. Data on the follicular turn-over, OR, OQ, and early stages of embryonic development were analyzed with mixed models using the PROC MIXED and GLIMMIX procedures of SAS. Results revealed that the number of medium sized follicles (LSM ± SEM) and rate of OR (%) were greater (P < 0.05) during PBS (2.76 ± 0.40; 61%) and TBS (1.73 ± 0.30; 54%) as compared to LBS (0.68 ± 0.30; 31%) in buffaloes, respectively. The OR rate was also greater (P < 0.05) using 17 G as opposed to 18 G needle (62% vs. 35%), however, there was no effect (P > 0.05) of season and G of needle on OQ in buffaloes. In experiment 2, the number of small (3.50 ± 0.63 vs.2.69 ± 0.60) sized follicles was higher (P < 0.05) in FA, whereas, medium (1.13 ± 0.45 vs. 1.59 ± 0.45) sized follicles were greater (P < 0.05) in CIDR-EB synchronized buffaloes. The OR rate (67% vs. 53%), and OQ (Grade I_+_II; 15% vs. 16% and Grade III_+_IV; 85% vs. 84%), remained similar (P > 0.05) in FA and CIDR-EB treated buffaloes, respectively. Similarly, rates of in-vitro maturation (66% vs. 59%), cleavage (42% vs. 53%), 4-cell (27% vs. 32%), 8-cell staged embryos (23% vs. 25%), and morula (13% vs. 8%) did not differ (P > 0.05) between FA and CIDR-EB methods of follicular wave emergence, respectively. Taken together, it is concluded that peak or transition breeding seasons are suitable to perform OPU using 17 G needle for maximum follicular turn-over, and OR in buffaloes. However, the two fundamental methods of synchronization of wave emergence resulted in similar efficiency for OPU derived in-vitro embryo production in Nili-Ravi buffaloes.