title: Effect of breeding season on in vivo oocyte recovery and embryo production in non-descriptive Indian river buffaloes (Bubalus bubalis).
abstract: The present study was carried out to examine the effect of season on in vivo oocyte recovery and embryo production in non-descriptive, Indian river buffaloes (Bubalus bubalis). Ovum pick up (OPU) was conducted twice a week for 8 weeks during peak (October-March) and low (April-September) breeding season in live buffaloes (n=6). OPU was performed using ultrasound equipment with a 5MHz transvaginal transducer, a single lumen 18-gauge, 55-cm long needle and a constant vacuum pressure of 110mmHg. The number and size of follicles was determined before puncture. The recovered oocytes were graded and only grade A and grade B oocytes were used for in vitro production (IVP) of embryos. The mean number of follicles observed per animal per session did not differed (P<0.05) between animals or between puncture sessions in both low and peak breeding seasons. Higher (P<0.05) number of follicles were observed (4.8+/-0.2 versus 3.1+/-0.3) and punctured (4.0+/-0.2 versus 2.4+/-0.2) during peak breeding season when compared to low breeding season. Oocytes recovered (1.6+/-0.1 versus 1.0+/-0.3) per animal per session were higher (P<0.05) in peak breeding season than low breeding season. During the peak breeding season, the blastocyst yield per animal per session (0.3+/-0.4 versus 0.18+/-0.4) was higher (P<0.05) than the low breeding season. However, season did not significantly affect the percentage of oocytes suitable for IVP (grade A+B) and blastocyst production rate. In conclusion, the efficiency of OPU combined with IVP was higher during the peak breeding season than the low breeding season in buffaloes.
authors.affiliation: Department of Animal Reproduction, Gynaecology and Obstetrics, Veterinary College, Karnataka Veterinary, Animal and Fishery Sciences University, Bangalore, India. drmanjunathvet@gmail.com
authors.forename: B M
authors.initials: BM
authors.lastname: Manjunatha
authors.forename: J P
authors.initials: JP
authors.lastname: Ravindra
authors.forename: P S P
authors.initials: PS
authors.lastname: Gupta
authors.forename: M
authors.initials: M
authors.lastname: Devaraj
authors.forename: S
authors.initials: S
authors.lastname: Nandi
mesh_terms: D000818:Animals; D002020:Buffaloes / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary*; D008297:Male; D054315:Oocyte Retrieval / Q000379:methods / Q000662:veterinary*; D006080:Ovarian Follicle / Q000000981:diagnostic imaging / Q000502:physiology* / Q000601:surgery; D011247:Pregnancy; D012621:Seasons; D014463:Ultrasonography