@article {KNIGHTS20031,
	title = {Effects of dosage of FSH, vehicle and time of treatment on ovulation rate and prolificacy in ewes during the anestrous season},
	journal = {Small Ruminant Research},
	volume = {50},
	number = {1},
	year = {2003},
	pages = {1 - 9},
	abstract = {The effects of dosage of follicle stimulating hormone (FSH), vehicle and time of injection on ovulation rate and prolificacy were evaluated during the anestrous season. Ewes on four farms (n=445) were treated with a CIDR-G{\textregistered} device for 5 days and exposed to rams upon removal of the insert (CRRI, day 0). A 3{\texttimes}2{\texttimes}2 factorial arrangement tested effects of dosage of FSH (Folltropin{\textregistered}; 0, 42 or 68mg NIH-FSH-P1), vehicle (saline:propylene glycol 1:4, v/v [PGL], or 50\% polyvinylpyrrolidone K 29{\textendash}32 [PVP]) and time of injection (12 or 36h before CRRI). Follicular growth was monitored by ultrasonography in four ewes per treatment at injection of FSH, at CRRI, and on days 1{\textendash}3 post-CRRI. All ewes were examined by ultrasonography on days 10{\textendash}14 for ovulation rate, and on days 26{\textendash}31 and 46{\textendash}51 for pregnancy and number of embryos. The largest follicle (F1) increased in diameter (mm) between FSH injection (5.3{\textpm}0.1) and day 1 (6.1{\textpm}0.1; P<0.01). The F1 was larger at CRRI (P<=0.05) in ewes receiving 42 than 0mg FSH, and 68 than 42mg FSH. The F2 increased in diameter (P<0.05) from FSH injection (4.7{\textpm}0.2) to CRRI (5.2{\textpm}0.2) and to day 1 (5.8{\textpm}0.2), but was not affected by treatment. Number of small follicles (<=4mm) did not differ with time or treatment. Number of medium follicles (5mm) declined (P<0.05) between FSH (1.5{\textpm}0.2) and days 1 (0.8{\textpm}0.2), 2 (0.9{\textpm}0.2), and 3 (0.5{\textpm}0.2). Number of large follicles (>=6mm) increased from FSH (0.6{\textpm}0.3) to CRRI (1.4{\textpm}0.3; P<0.05), and day 1 (2.3{\textpm}0.3; P<0.05), then declined by day 3 (0.6{\textpm}0.3; P<0.05). There were more large follicles at CRRI (P<0.05) with 68mg (2.1{\textpm}0.3) or 42mg (1.6{\textpm}0.2) than 0mg (0.5{\textpm}0.4) FSH. Ovulation rate (mean 2.12{\textpm}0.05) increased with FSH given 12h, but not 36h before CRRI (dosage {\texttimes} time, P<0.05). Estrous response, conception rate, percentage of ewes lambing or prolificacy did not differ. However, number of corpora lutea not represented by embryos increased with dosage of FSH (P<0.01; 0.25{\textpm}0.14, 0.55{\textpm}0.09, 0.71{\textpm}0.09 for ewes treated with 0, 42, and 68mg FSH, respectively).},
	keywords = {Anestrus, Ewes, Follicle stimulating hormone, Follicular dynamics, Ovulation rate, Progesterone, Prolificacy},
	issn = {0921-4488},
	doi = {https://doi.org/10.1016/S0921-4488(03)00111-1},
	url = {http://www.sciencedirect.com/science/article/pii/S0921448803001111},
	author = {M. Knights and Q.S. Baptiste and A.B. Dixon and J.L. Pate and D.J. Marsh and E.K. Inskeep and P.E. Lewis}
}
