Performance of Broiler Breeder Males Given Low Protein Feed

Abstract

One hundred and eight 24-wk-old broiler breeder males were arranged into 18 groups of six birds of equal average BW. Six groups were killed for carcass evaluation at 24 wk of age; the other 12 groups were divided between two dietary treatments. One treatment was a typical breeder-recommended male broiler breeder ration (standard, or ST; 12% CP, 3,160 kcal ME/kg), whereas the other was a low-protein, corn-based diet (all corn, or AC; 8% CP, 3,220 kcal ME/kg) formulated to approximate minimum amino acid requirements for positive nitrogen balance. All birds were fed at a rate of 325 kcal ME/day per bird to 68 wk of age. Body weight, semen volume, and sperm concentration were evaluated weekly. All birds remaining at 68 wk were killed for carcass evaluation. Feed and age effects on BW were highly significant (P less than .001). However, birds did not respond similarly to treatments with increasing age. Birds fed ST were heavier and surpassed breeder-recommended BW by 38 wk of age, whereas birds given AC were lighter and remained below breeder-recommended weights throughout the study. Semen production was measured by semen volume, sperm concentration, total sperm yield, and proportion of males producing semen; values were similar for treatments at all ages. Birds given the AC feed had more carcass fat than ST-fed birds at 68 wk of age, but ST-fed birds had the same proportion of fat at 68 wk as birds killed at 24 wk. Results suggest that the amino acid levels provided by the AC diet were less than adequate for optimal BW gain, but adequate for semen production.

The effect of crude protein intake on sperm quality of young and old male broiler breeders

“…No significant response in sperm concentration or sperm mobility index to cumulative CP intake was observed in any of the groups. The lack of response in sperm concentration to CP intake is similar to that observed by Wilson et al (1988) and Revington et al (1991). Sperm mobility, however, has not previously been used to assess the impact of CP intake, and the results from this experiment show no response in sperm mobility index to CP intake.…”

“…While this may be of practical value, crude protein (CP) is one of the most costly components of the feed, and the nutrient requirement of males for protein is lower than that of females. Previous research has suggested that male breeders can be fed lower CP diets with no adverse effects on semen quality or testes characteristics (Wilson et al, 1988, Hocking, 1989, Revington et al, 1991. There was no effect of feeding of a 9% CP diet on semen volume, concentration, number of spermatozoa per ejaculate or testes weight (Wilson et al, 1987), or feeding an 8% CP diet on semen volume or metabolic activity of spermatozoa (Hocking, 1989).…”

The Nutritional Requirements of Protein for Sinai Cocks

“…Wilson et al (1988) showed no effect of feeding 9, 12 or 15% protein were observed on semen volume, concentration, number of spermatozoa ejaculated or spermatogenic activity. No differences in sperm volume, sperm concentration, total sperm yield and the proportion of males producing semen were observed from males fed either 8 or 12% CP (Revington et al, 1991). There were no differences in fertility between males fed 12 or 16% CP (Hocking and Bernard, 1997).…”

The effect of dietary crude protein on the fertility of male broiler breeders

“…No effects on semen volume or metabolic activity of the spermatozoa were observed in males fed different CP diets from 80 to 400 g CP/kg (Hocking, 1989). No differences in semen volume, sperm concentration, total sperm yield and the proportion of males producing semen were observed from males fed either 8% or 12% CP (Revington et al, 1991). No effects of feeding 9%, 12% or 15% protein were observed on semen volume, concentration, number of spermatozoa ejaculated or spermatogenic activity (assessed by means of histological evaluation of the seminiferous epithelial area, tubule diameter and epithelial height) (Wilson et al, 1988).…”