RESUMEN
The aim of this work was to study estrus synchronization and fixed time artificial insemination (FTAI) in dairy buffaloes during season anestrus. One hundred thirty-nine dairy buffaloes in seasonal anestrus were divided in two groups as G1(n=66) and G2(n=73). The protocols for both the groups were the same until day (D)14:D0 administration of 2.0 mg estradiol benzoate and implantation of progesterone device (P4) for 14 days; D14 removal of P4 plus 150 mg of cloprostenol and 400 IU of equine chorionic gonadotropin. On D16, G1 received 10 mg of buserelin and G2 100 mg deslorelin acetate. On D17, both the groups were submitted to FTAI. Ultrasonographic examinations of ovaries were performed on D0, D14, D16 and D17. Results showed that pregnancy rates in G1 and G2 were 20 and 41% (p<0.05) and the ovulation rates were 16.6 and 37%, respectively (p<0.05). The dominant follicle (DF) diameter on D16 was 7.9 mm in G1 and 8.9 mm in G2 (p>0.05). Thirty-five percent of the animals in G1 and 54.1% in G2 showed a diameter DF greater than 8.0 mm on D16 (p>0.05). Thus, it could be concluded that the protocols synchronized the estrus, leading the concentration of the parturitions in the period of low milk production. Deslorelin was more efficient than buserelin due the higher percentage of DF ovulation and higher pregnancy rates.
RESUMEN
The aim this study was to compare two protocols of induction for ovulation by desloreline acetate and hCG in Quarter Horse mares. The choice of the animals was based on the observations by the estrus, by rectal palpation of the ovaries and by ultrassonography of the follicular dynamics. After estrus detection and follicle control, the measurement of the follicles and the classification of uterus were carried out. The animals that had dominant follicle (diameter more than 35 mm) and swollen uterus were used. In these conditions, the mares received hCG or desloreline acetate. Once ovulation occurred, the artificial insemination was carried. Two groups were performed: G1 (20 animals) received 1.5 mg desloreline acetate and G2 (20 animals) received 1700 IU of hCG. Following 6h intervals, the control follicular was performed by ultrasonography. The follicular average diameter was 42.6 cm for the groups and set up a score of 0 to 3 of uterine edema displayed by the device as well as the time of ovulation. In conclusion, the desloreline acetate showed better performance than hCG, because the ovulation was induced in less time (nine hours than hCG) (p<0.05).The pregnancy rate was 80 and 75 percent, respectively in G1 and G2.
RESUMEN
The efficacy of one or multiple doses of an injectable formulation of deslorelin (a GnRH agonist) was evaluated to induce estrus in anestrous bitches. Thirteen animals composed three groups: group 1 (n=5, single IM injection of 2mg deslorelin), group 2 (n=5, four IM injections of 2mg deslorelin in alternate days), and control group (n=3, four IM saline injections in alternate days). Daily clinical evaluations, sexual behavior, vaginal cytology, plasma progesterone concentration, ovaryhysterectomy and macroscopic evaluation of the uterus and ovaries were done. In group 1, none of the bitches showed signs of estrus, while two developed clinical signs and vaginal cytology of proestrus. In group 2, all animals presented proestrus, four presented estrus, and three ovulated; resulting in a functional corpus luteum and high progesterone concentration until day 25 of diestrus, when ovaryhysterectomy was performed. The duration of the stages of deslorelin induced cycles and the progesterone profile were similar to those described in the literature, and no side effects were observed. In conclusion, injectable formulation of deslorelin in multiple injections was effective to induce fertile estrus in anestrous bitches.
Avaliou-se a eficácia de uma formulação injetável de deslorelina (agonista do GnRH) na indução de estro em cadelas no anestro e seus efeitos no aparelho genital, com uma ou múltiplas aplicações. Treze animais compuseram os grupos: grupo 1 (n=5, 2mg de deslorelina via IM), grupo 2 (n=5, quatro injeções IM de 2mg de deslorelina em dias alternados) e grupo-controle (n=3, quatro injeções IM de solução salina em dias alternados). Foram realizadas avaliações clínicas diárias do comportamento sexual, da citologia vaginal, da dosagem de progesterona plasmática, da ovario-histerectomia e avaliação macroscópica do útero e dos ovários. No grupo 1, as cadelas não exibiram sinais de estro, mas duas apresentaram sinais clínicos e citologia vaginal compatíveis com proestro. No grupo 2, todas apresentaram sinais de proestro, quatro de estro e três ovularam, resultando em corpos lúteos funcionais e concentração elevada de progesterona plasmática até o 25º dia de diestro, quando foi realizada a ovario-histerectomia. Os sinais clínicos, a duração das fases e a curva de progesterona dos ciclos induzidos foram semelhantes aos descritos na literatura, e não foi observado efeito colateral do tratamento. Concluiu-se que a formulação injetável de deslorelina com múltiplas aplicações foi eficaz na indução de estro em cadelas em anestro.