Endocrine and ovarian responses in water buffalo cows immunized against inhibin and subjected to the Ovsynch protocol

The aim of this study was to investigate the feasibility of stimulating ovarian fol icle development in order to improve fertility in water buffalo cows by immunization against inhibin. The experiment was carried out in early summer (May) and included 24 multi-parity crossbred Murrah-Swamp buffaloes that were divided into immunized (n=11) and control (n=13) groups. Each immunized cow was administered with a 2-mL immunogen of mineral oil adjuvant containing 2 mg of recombinant inhibinα-subunit fusion protein. The controls were treated with the adjuvant only. Al animals received Ovsynch protocol treatment, starting on the day of the antigen administration, and they were artiifcial y inseminated upon behavioral estrus. As a result, al of the immunized buffaloes generated antibodies against inhibin during the experimental period and had higher plasma concentrations of fol icle-stimulating hormone (FSH), activin, and estradiol (E2) related to estrous expression. A higher proportion of immunized animals expressed estrus behavior than did the controls (72%vs. 30%, P<0.05). On aver-age, inhibin-immunized buffaloes had signiifcantly more large fol icles (≥9 mm in diameter) than the controls (mean±SEM;1.2±0.1 vs. 0.84±0.1, respectively;P<0.05) and a slightly higher mean total number of fol icles (≥2 mm;11.4±0.7 vs. 9.0±1.1, respectively;P=0.09) and smal (2–4 mm) fol icles (8.81±0.6 vs. 6.84±1.0, respectively;P=0.12). A higher percentage of cows ovulated in the immunized group than in the control group (91%(10/11) vs. 54%(7/13), respectively;P<0.05). Moreover, inhibin-immunized cows had slightly larger corpus luteum (CL) than the controls 9 days after ovulation and signiifcantly higher (P<0.01) post-ovulation peak plasma progesterone (P4) concentrations. Immunization against inhibin also mar-ginal y increased the conception rate 42 days after insemination (45.8%vs. 15.4%;P>0.05). These results demonstrate that immunization against inhibin, coupled with the treatment with the Ovsynch protocol, can constitute a new technique to increase fertility in water buffalo cows.

Response of primiparous and multiparous buffaloes to yeast culture supplementation during early and mid-lactation

Strains of live Saccharomyces cerevisiae yeast have exhibited probiotic effects in ruminants. This study investigated the effects of the dietary yeast supplement, S. cerevisiae(Yea-Sacc^(1026)), on primiparous(PP)and multiparous(MP) Egyptian buffaloes in early to mid-lactation. Lactating buffaloes were fed either a basal total mixed ration(TMR, control; 4 PP and 8 MP) or the basal TMR plus 10 g Yea-Sacc^(1026) per buffalo cow per day(yeast; 4 PP and 8 MP). The feeds were given from 15 days prepartum to 180 days postpartum. Feed intake, body weight, and milk yields(MY) were recorded, and milk and blood samples were collected for analyses. Feces were collected from days 45 to 47 during early lactation and from days 90 to92 during mid-lactation to determine apparent digestibility of dry matter(DM), organic matter(OM),crude protein(CP) and crude fiber(CF). Energy corrected milk yield(ECM), feed conversion, and energy and nitrogen conversion efficiency were calculated. Yeast treated MP buffaloes consumed more DM(P < 0.041) and CP than the untreated control group. Apparent digestibility of DM and OM were significantly greater at mid-lactation for treated versus control group(P = 0.001). Crude fiber digestibility was greater in MP than in PP buffaloes(P = 0.049), and yeast supplemented MP cows had a greater CF digestibility than control MP buffaloes at mid-lactation(P = 0.010). Total blood lipids decreased after yeast supplementation(P= 0.029). Milk yields, ECM, fat and protein yields increased for yeast treated MP buffaloes(P < 0.039). The study concluded that the response to yeast supplementation in buffalo cows is parity dependent. Multiparous buffaloes respond to yeast supplementation with an increased DM intake and CF digestibility without significant weight gains, allowing a greater ECM yield with less fat mobilization. Supplementing buffaloes with yeast culture may increase milk production in early lactation and results in a more persistent milk production during mid-lactation. Feed conversion and energy and nitrogen conversion efficiency may be increased with the use of yeast supplementation in Egyptian buffaloes.