Corpus luteum function and embryonic mortality in buffaloes treated with a GnRH agonist, hCG and progesterone

Efficiency of two timed artificial insemination protocols in Murrah buffaloes managed under a semi-intensive system in the tropics

“…Conception rates achieved with the ovsynch protocol in this study are within the range reported in cycling lactating buffaloes in Europe (De Rensis et al 2005;Campanile et al 2007;Neglia et al 2008) and Asia (Paul and Prakash 2005). However, our results do not support the advantage of presynch-ovsynch over ovsynch previously reported in cattle (Moreira et al 2001;Navanukraw et al 2004).…”

“…For a successful establishment of early pregnancy, the timing of P 4 increase (i.e., early rise before day 6) is more critical than the total P 4 concentrations achieved (Wathes et al 2003). If this applies to buffaloes, it would explain partially the lack of effect on pregnancy rates of treatments designed to increase P 4 concentrations that were applied 5 days after AI (Campanile et al 2007). Campanile et al (2008) suggested that both maternal recognition of pregnancy and attachment of the conceptus are the two critical periods that should be Values are based on animals that ovulated targeted for P 4 supplementation to increase the chances of maintaining pregnancy during the first trimester in buffaloes.…”

“…One approach to circumvent this problem is the use of protocols for synchronization of ovulation (i.e., ovsynch and its several variations), which allow a fixed-time AI without the need for estrus detection (De Rensis and López-Gatius 2007). The ovsynch protocol has been tested in cycling lactating buffaloes in Asia (Paul and Prakash 2005) and Europe (De Rensis et al 2005;Campanile et al 2007;Neglia et al 2008), yielding pregnancy rates ranging from 30-52%. In Latin America, work with the ovsynch protocol has been conducted mainly with non-lactating buffaloes for beef production, in which pregnancy rates from 48% to 56% were obtained (de Araujo Berber et al 2002;Baruselli et al 2003).…”

Impact of buserelin acetate or hCG administration on day 5 post-ovulation on subsequent luteal profile and conception rate in Murrah buffalo (Bubalus bubalis)

“…Progesterone is required not only to maintain a suitable uterine environment for the development of the conceptus but also inhibits luteolysis; first, by decreasing sensitivity to oxytocin (Grazzini et al, 1998;Spencer and Bazer, 1995) and secondly, by enhancing conceptus development . In Italian Mediterranean buffalo, on day 5 post-AI administration of M a n u s c r i p 3 buserelin and hCG increased milk whey progesterone concentrations on day 15 but the incidence of embryonic mortality was not reduced (Campanile et al, 2007). However, in cattle embryonic mortality was reduced by treatment with GnRH on day 5.…”

“…The opportunity to suppress luteolytic mechanisms through hormonal approaches before the maternal recognition of pregnancy is a possible strategy for improving the conception rate in dairy animals. To prevent luteal deficiency induced early embryonic mortality, administration of gonadotropin releasing hormone (GnRH; Campanile et al, 2008b;Rastegarnia et al, 2004), human chorionic gonadotropin (hCG; Campanile et al, 2007;Marques et al, 2002) and progesterone (Pandey et al, 2013a) was used in cattle and buffalo. The mid-luteal phase GnRH administration improves luteal functions and luteinizes developing follicles to suppress the circulating estradiol (Thatcher et al, 2003).…”