The biological basis of sustained fertility in broiler and turkey hens is their capacity to store sperm in the oviductal sperm storage tubules (SST) located in the uterovaginal junction. The objectives of this study were to determine if the numbers of SST varied between 4 strains of broiler breeders and determine the number of SST in the turkey before (less than 9 d of photostimulation) and after (up to 22 d of photostimulation and laying) photostimulation. No statistical differences were observed in SST numbers in the 4 strains of broilers examined or in turkey hens before and after the onset of egg production. The mean numbers of SST for broilers and turkeys were 4,893 and 30,566, respectively. We conclude that any differences between the fertility of the 4 broiler breeder strains examined cannot be explained by differences in SST numbers. However, differences in the duration of fertility between broilers and turkeys are, in part, related to their respective numbers of number of SST. Furthermore, we conclude that turkey SST are morphologically differentiated and functional before the onset of photostimulation and while the oviduct is morphologically undeveloped.

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Primary Audience: Broiler Breeder Managers, Flock Supervisors, Researchers SUMMARYFeed restriction is an important tool used in the rearing of broiler breeders to control growth and maintain BW. Feed restriction during the growing phase typically provides 60 to 80% less feed than the birds would consume if provided feed ad libitum, resulting in a perceived animal welfare issue. Because males are typically more rigorously feed restricted than females, this is thought to be especially stressful to the growing cockerels. During this time, the reproductive systems of the males are undergoing formative stages, and improper management can have lifelong effects on their reproductive performance. Therefore, the objective of this study was to rear males under feed management programs that would require less severe feed restriction while still rearing replacement breeder males to the recommended target BW of 3.060 kg at 24, 21, 18, 15, and 12 wk of age, respectively. Males were placed at 3-wk intervals so that all males were light stimulated on the same calendar date and at the same time and BW but at different ages. A total of 5 treatment groups were used, based on age of the male at light stimulation. All males were reared in the same light-controlled house at the University of Arkansas Research Farm. Males were light stimulated and testicular development, semen analysis, fertility, and mating activity were recorded for each group of males. To measure semen production, males were housed in individual cages, with 24 males from each treatment group tested. Males light stimulated at 18 wk of age had the highest semen volume (0.46 mL), followed by males light stimulated at 24 (0.31 mL), 15 (0.29 mL), 21 (0.27 mL) and 12 wk of age (0.27 mL), respectively. Sperm count per ejaculate was highest for the males light stimulated at 18 wk of age, followed by males light stimulated at 21, 24, 15, and 12 wk of age, respectively. Males that were 21 wk of age or older at the time of light stimulation responded quicker to light stimulation than did younger males.

Primary Audience: Researchers, Broiler Breeder Managers SUMMARYWhile conducting research on testicular development in Gallus domesticus, it was noticed that several of the males had nodules on their testes. On further histological investigation, we observed that these nodules were composed of seminiferous tubules that were contained within the tunica vaginalis of the testicular capsule. The seminiferous tubules within these nodules contained sperm and spermatids at various stages of development; however, no direct outlet of the sperm into the testes was identified or observed. These testicular nodules were found in the most common primary breeder males investigated from 9 flocks, with occurrences for individual males (n > 450) ranging from 42 to 93%. The flocks that were investigated consisted of commercial breeder flocks, individually caged males, and males used in pen trials. Nodules were also found in a pure line of French Mottled Houdan chickens as well as in a randombred broiler breeder line from the 1980s. The majority of nodules were observed on a single testis, the left testis in 90.3% and the right testis in 0.6%, with 9.032% of males with nodules on both testes. The number of visible nodules on the testes ranged from 1 to as many as 18, with the size ranging up to 4.5 mm. Using histological preparations, we detected these testicular abnormalities in males as young as 18 wk of age and in males that had not been light stimulated. No conclusion about the effects of testicular nodules on fertility was apparent because all the flocks investigated had normal or higher fertility. Therefore, the etiology and subsequent effects of these testicular nodules in roosters are unknown.

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