Restriction of day length or feed consumption of winter-hatched Broad Breasted White turkey males were evaluated for their effects on reproductive performance. Sixty-four turkey males, 18 weeks of age, were selected on the basis of conformation and body weight and randomly divided into four treatment groups. Treatments differed with respect to feeding and lighting schedules as follows: (1) full-fed; ambient light, 18-28 weeks of age; 15L/9D, 28-66 weeks of age; (2) restricted-fed, light schedule as in (1); (3) full-fed, 12L/12D, 18-66 weeks of age; and (4) full-fed; 8L/16D, 18-66 weeks of age. Individual body weights and group feed consumption were determined for each treatment. Individual males were periodically evaluated for semen quality and quantity, beginning at 32 weeks of age. Four groups, each containing 16 individually caged females, were inseminated with pooled semen from the respective male treatment groups to determine fertility during a 20-week egg production period.Restricting daily feed consumption to approximately 50% of the feed consumed by full-fed males resulted in a 30% reduction in body weight at 30 weeks of age; body weight for restrictedfed males was significantly less (P<.05) than that of full-fed males through 65 weeks of age. Regression analysis of semen volume indicated that restricted-fed males receiving 15 hours of light, and full-fed males receiving either 12 or 8 hours of light per day, produced increasing semen volumes over a 30 week collection period (from 32 to 62 weeks of age), while full-fed males receiving 15 hours of light per day exhibited a decline in semen production. Fertility of eggs from B.B.W. turkey hens, inseminated with semen from restricted-fed males was significantly (P<0.05) higher than fertility following inseminations from full-fed male groups receiving 15, 12 or 8 hours of light per day.The seasonal decline in semen quality and quantity, often experienced in turkey breeder males, was prevented through the use of the feed restriction program. Males in the restricted-fed group were also easier to handle and ejaculate than males from the full-fed groups. Restricting feed intake resulted in a 55% saving in feed consumed.

To determine if excessive body weight and dietary protein and amino acid intake contribute to the incidence of leg deformities, the growth of male turkeys was restricted from 6 to 12 wk and from 6 to 20 wk of age by feeding diets for ad libitum intake that were low in dietary protein and amino acids (74% of controls). For those turkeys whose growth was restricted from 6 to 12 wk of age, a return to control diets (low compensatory plane) or to 20% above control diets (high compensatory plane) with respect to protein and amino acids resulted in live body weights comparable with controls at 20 wk of age. Feed to gain ratios (0 to 20 wk) were comparable between compensated and control birds, and protein efficiency was improved for birds fed the low compensatory plane diets. Restricting growth significantly lowered the incidence of leg abnormalities at 12 wk of age (P less than .05), as compared with controls, but by 20 wk, only birds fed the low compensatory plane diet showed a lowered incidence (P less than .06). These results on leg abnormalities (mainly valgus-varus deformities) suggest that rapid weight gains or dietary protein and amino acid intake may contribute to the leg weakness syndrome but is certainly not the only factor involved.

Large White turkey breeder hens were used to evaluate the effect of three different levels of physical feed restriction on subsequent reproductive performance. The feed treatments were: 1) fed ad libitum throughout the study (CC), 2) feed-restricted from 16 to 24 wk (CR), 3) feed-restricted from 3 to 16 wk (RC), and 4) feed-restricted from 3 to 24 wk (RR). Feed restriction was implemented so that restricted-fed hens (RC and RR) achieved a 45% reduction in BW as compared to CC hens at 16 wk. From 16 to 24 wk, feed was allotted to RR and CR hens to maintain a slight increase in BW. At the completion of the respective restriction periods, hens were gradually returned to ad libitum feeding. At 30 wk of age, hens were photostimulated for a 20-wk summer season egg production cycle. Hens receiving RC and RR treatments laid significantly more eggs than did CC and CR hens for the first 5 wk of lay. However, once the house temperature increased to 26.7 to 29.4 C during 6 to 10 wk of lay, egg production of all hens decreased, resulting in a significant decrease in cumulative egg production for RR and RC hens compared to CC and CR hens. Egg and poult weights were less for RC and RR hens compared to those from CC and CR hens. In conclusion, age of breeder, season of implementation, and length of physical feed restriction have significant effects on the reproductive performance of turkey breeder hens.

Large White turkey breeder hens were used to evaluate the effect of three different levels of physical feed restriction on subsequent body and carcass composition. The four feed treatments were 1) ad libitum fed throughout the study (CC), 2) feed restricted from 16 to 24 wk (CR), 3) feed restricted from 3 to 16 wk (RC), and 4) feed restricted from 3 to 24 wk (RR). Feed restriction was implemented so that RC and RR hens achieved a 45% reduction in BW compared to CC hens at 16 wk. From 16 to 24 wk, feed was allotted to RR and CR hens to maintain a slight increase in BW. At the completion of each restriction period, hens were gradually returned to ad libitum feeding. At 30 wk, hens were photostimulated for a 20-wk summer season egg production cycle. Restricted fed hens had increased moisture levels at 16 and 30 wk and decreased fat levels at 16, 30, 39, and 54 wk (P < or = 0.05). Absolute and relative weights of the pectoralis major muscle were greater in hens fed ad libitum through 43 wk (P < or = 0.05). There were no differences in the number of maturing yellow follicles due to treatment. However, restricted fed hens had higher peak egg production during early lay but decreased subsequent and cumulative egg production. Changes in egg production were associated with changes in breast muscle weight. Prolactin levels were greater in hens in-production compared to hens out-of-production; however, there were no differences due to feed treatment. In conclusion, further research on quantitative feed-restriction programs, which result in body weight reductions as described in this study, should address specific physiological and nutritional requirements and not be implemented as general programs.

A comparison between initial inseminations of Large White turkey hens prior to or after onset of egg production was undertaken to determine the effect on fertility. Semen from Bronze toms was utilized for the initial inseminations whereas all subsequent inseminations utilized White sires. After 10 weeks there were no significant differences between treatments for percent egg production or hatchability. Inseminating prior to the onset of egg production resulted in a significantly different (P less than or equal to .05) 8-week average of 97.5% fertility in the early insemination (EI) group as compared to an average of 90.4% in the late insemination (LI) group. Differences between the EI and the LI groups were greatest during the last 2 weeks of the experiment during which the EI hens maintained higher levels of fertility. Bronze poults were observed in the EI progeny following three subsequent inseminations with semen from White sires, whereas no Bronze poults were obtained from the LI hens following the third subsequent insemination with White semen.