Evaluation of synchronization of ovulation for fixed timed insemination in buffalo (Bubalus bubalis)

Abstract

0.05). The dose of GnRH (10mg vs. 20mg) and the progesterone concentration did not interfere in ovulation in the beginning of the treatment (P>0.05). Animals that ovulated (n = 20) after the first GnRH injection presented larger follicular diameter (P <0.01) that those that no ovulated (n=13). In PGF2alpha injection, the follicular diameter was 10.3 ± 2.0mm. The Group 1 presented larger follicular diameter than the Group 2 (P <0.01). Animals that ovulated after the first GnRH injection (n=20) presented higher progesterone concentrations in the day of PGF2alpha injection (P <0.05). It was observed that 78,80% female buffaloes treated presented synchronized ovulation and, the first dose of GnRH did not interfere in the efficiency of the protocol (P>0.05). In Experiment 2, it was observed conception rate of 45.40% (n = 1053). Animals synchronized during the favorable reproductive season presented better conception rate than the unfavorable season (48.80% vs. 6.90%; P <0.05). The conception rate was influenced by body condition score of the animals and parity during the favorable reproductive season (P <0.05). The conception rates did not differ according to the year (1998 and 1999) of artificial inseminations and the postpartum period in the beginning of the treatment (P>0.05). In summary, the Experiments indicated that the use of synchronization of the ovulation for fixed timed insemination, during the favorable reproductive season, presents satisfactory results in buffalo and could still be better when used multiparous buffaloes with good body conditon score in the beginning of the treatment.]]>

Estrus synchronization and Fixed Time Artificial Insemination (FTAI) in dairy buffaloes during seasonal anestrus

“…However, these authors applied the P 4 protocol added by the administration of eCG or the Ovsynch protocol in the animals that were cycling (40.9%). Other studies demonstrated that when the Ovsynch protocol was used in female buffaloes during the unfavorable reproductive season (seasonal anestrus), the conception rates were quite variable: 28.2% ; 6.9% (Baruselli et al 2003); 34% (Campanile et al 2005); 30% (Warriach et al 2008). In the present study, deslorelin acetate was used to induce the ovulation (GnRH agonist), which resulted in conception rates (39.6%) higher than the rates reported in other studies using the Ovsynch protocol, indicating that deslorelin acetate was more efficient in female buffaloes under these conditions.…”

“…The reproductive seasonality of the dairy buffalo is the physiological factor that exerts the greatest impact on this economic activity. The highest concentration of parturitions in this species is seen from March to June in the Southern and Southeastern Brazil (mainly between parallels 24 and 26), and it determines the concentration of milk production until September, with a significant reduction, or even absence of milk in the summer months (Baruselli et al 2003). In this region, poor buffalo farmers depend heavily on the milk production from the buffaloes.…”

“…Many female buffaloes present prolonged periods of anestrus during the unfavorable breeding season (spring/ summer) and do not respond properly to the treatment with only the Ovsynch protocol. Protocols using P 4 , estradiol, prostaglandin, GnRH, and eCG improve the pregnancy rates in female buffaloes (Baruselli et al 2003). The use of deslorelin acetate (a GnRH agonist) has been reported in the dogs (Trigg et al 2006), cattle (Bergfeld et al 1996;Ambrose et al 1998;Ramajahendran et al 1998;Bartolome et al 2004;Padula and Macmillan 2005;Silvestre et al 2009), horses (Mckinnon et al 1993;Squires et al 1994;Mumford et al 1995;Vanderwall et al 2001;Melo et al 2005;Raz et al 2009;Lindholm et al 2010) and sheep (Schneider and Rehbock 2003).…”

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

“…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). According to De Rensis et al (2005), the standard ovsynch protocol should be applied only in buffalo cows presenting a functional corpus luteum (CL) and a large follicle (≥10 mm) determined by ultrasonography at the beginning of treatment.…”

Associação da medroxiprogesterona ao protocolo Ovsynch para inseminação artificial em tempo fixo de búfalas cíclicas (Bubalus bubalis) criadas na Amazônia Oriental

“…O diâmetro médio dos maiores folículos presentes nos ovários ao início do tratamento foi de 8,85 ± 1,63 mm no G1 e 10,0 ± 1,29 mm no G2, indicando que os animais de ambos os grupos apresentavam condições satisfatórias para ovular após a primeira administração do GnRH, uma vez que esse evento ocorre em 70,5% das búfalas com folículos de diâmetro de 8,0 ± 1,9 mm, conforme Baruselli et al (2003). De fato, no D7, foram detectados corpos lúteos nos ovários de 9 das 14 fêmeas do G1 (64,28%) e em 8 das 13 fêmeas do G2 (61,53%), o que conferiu uma taxa de ovulação total de 62,96% (n=17/27) após a primeira administração de GnRH.…”