Ovarian follicular growth and maturity and follicular production of progesterone and oestradiol in response to porcine luteinising hormone and porcine follicle stimulating hormone in albino ( S*AS ) hens in vivo and in vitro

Abstract

1. The effects of the S*AS gene on follicular growth were studied by feeding Sudan IV and Sudan Black B, on follicular maturity by measuring P4 and E2 output of the 5 largest follicles (F1 to F5) in vitro , and on ovarian response (plasma progesterone, P4, and oestradiol, E2) to administration of porcine follicle-stimulating hormone (pFSH) and porcine luteinising hormone (pLH) in old laying hens. 2. Albino hens had fewer dye rings in the yolks of their eggs than non-albinos (8 32 compared to 8 59) and the yolks from albinos weighed less. The numbers of normal and atretic follicles larger than 3 mm in diameter did not differ between the two genotypes. 3. The P4 outputs from the F1 and F2 follicles were significantly greater for albino hens, but P4 production of other follicles was not different for the two genotypes. The P4 output of the F1 follicle in response to pLH was dose-dependant and greater for albino hens than for non-albinos. Porcine LH did not increase the follicular E2 output in either genotype. 4. Administration of pLH, but not pFSH, increased plasma P4 and E2 concentrations, with no difference between genotypes. 5. These data suggest that the F1 follicles for albino hens are precocious, resulting in a reduced growth period and a smaller weight at ovulation.