Duration of Fertility in Ad Libitum and Feed-Restricted Caged Broiler Breeders

Abstract

It has been shown in previous studies that fertility can be reduced in overweight broiler breeder (BB) flocks. In an effort to determine the effect of ad libitum feeding on the duration of fertility in BB hens, 60 52-wk-old Shaver Starbro hens were randomly assigned to one of two treatments, ad libitum feeding (F) or restricted feeding (R) to maintain breeder target weights. All hens were reared to 52 wk under conditions of feed restriction. All birds were weighed individually on a weekly basis. At the beginning of each of two 4-wk study periods (56 to 60 wk and 60 wk to 64 wk), all birds were inseminated on 2 consecutive d with 0.05 mL pooled BB semen. All eggs were weighed and placed in a forced air incubator the same day that they were laid. After 7 to 10 d of incubation, the eggs were broken out and scored macroscopically as fertile with live embryo, fertile with dead embryo (early embryonic death), or clear (assumed infertile). The duration of fertility was defined as the number of days from the day after the second insemination to the last fertile egg before two consecutive interfile eggs. Hen BW were significantly different between treatments within each of the two 4-wk studies. The mean BW of the F hens was 4,261 g in Study 1 and 4,448 g in Study 2. The BW of the R hens were 3,459 g in Study 1 and 3,565 g in Study 2. Egg production levels and average egg weight was not different between treatments in either study. In Study 1, the duration of fertility for the F hens (12.7 d) and the R hens (12.7 d) were not different. In Study 2, the durations of fertility were significantly higher (P < 0.05) in the R hens (12.7 d) than in the F hens (10.0 d). These results support the theory that overweight BB have a reduced duration of fertility that may contribute to a reduced fertility in artificially inseminated and naturally mated flocks.

Analysis of sperm storage ability using duration of fertility in hens

“…This finding differs from that for broiler breeders (Goerzen et al, 1996); the reason may be that hens were at different ages and had different amounts of fat deposit which greatly influences body weight, laying rate and reproduction performance (Bilgili and Renden, 1985). In an earlier study, Beaumont et al (1992) reported a positive relationship between laying rates and duration of fertility in laying hens, whereas we found a negative relationship between these variables.…”

“…Although duration of fertility may be predicted from data obtained from egg collection intervals of 18 to 21 d (Kirby and Froman, 1990), such an interval may seem impractical, especially if overall fertility is the only variable of interest. Previous work has indicated that DF varies with laying intensity (Beaumont et al, 1992;Goerzen et al, 1996). The aim of this study was to determine which one of the three means of describing fertility is best for assessing the ability of storing sperm in hens and whether fertility and laying intensity should be combined with this assessment.…”

“…At present, there are three definitions to describe the duration of fertility: the efficient duration of fertility (De), defined as the number of days between AI and the first clear egg (Beaumont et al, 1992); the maximum duration of fertility (Dm1), defined as the number of days from the day after AI to the last fertile egg before two consecutive infertile eggs (Goerzen et al, 1996); the maximum duration of fertility (Dm2), defined as the number of days from the day after AI to the last fertile egg (Brillard et al, 1998). Although duration of fertility may be predicted from data obtained from egg collection intervals of 18 to 21 d (Kirby and Froman, 1990), such an interval may seem impractical, especially if overall fertility is the only variable of interest.…”

The effect of dietary energy and protein levels on production in breeding female ostriches

“…Rosebrough et al (1983) found that energy and protein utilisation for egg production in large white turkeys was better in birds fed lower protein and energy diets and Scott et al (1999) found that feeding laying hens diets containing protein levels between 16 and 19% had no significant effect on egg production. Similarly, Goerzen et al (1996) reported no difference in egg production between hens fed ad libitum and those on a restricted diet. Malden et al (1979) indicated that if broiler breeders were allowed to get too fat, egg production would be depressed during the laying period possibly because, as suggested by Badley (1997), excess fat deposits can prevent eggs from being deposited in the oviduct.…”

Feeding management strategy for male broiler breeders and its effects on body weight, hatchability and fertility

“…The continuous genetic improvement of broilers, particularly for rapid growth, better feed efficiency, and higher meat yield implies in constant changes in bird management and feeding. In broiler breeders, in particular, this means preventing the negative effects of excessive body weight on reproductive performance (Goerzen et al, 1996;Barbato, 1999;Romero-Sanchez et al, 2007).…”