Stocking density affects the growth performance of broilers in a sex-dependent fashion

Abstract

The effects of stocking density, sex, and dietary ME concentration on live performance, footpad burns, and leg weakness of broilers were investigated. A total of 876 male and 1,020 female 1-d-old chicks were placed in 24 pens to simulate final stocking density treatments of 26 kg (LSD; 10 males or 12 females/m(2)) and 42 kg (HSD; 16 males or 18 females/m(2)) of BW/m(2) floor space. Two series of experimental diets with a 150 kcal/kg difference in ME concentration (2,800, 2,900, and 3,000 or 2,950, 3,050, and 3,150 kcal of ME/kg) were compared in a 3-phase feeding program. The HSD treatment significantly decreased BW gain and feed conversion ratio (FCR). The HSD chickens consumed less feed by 35 d of age; thereafter, the reverse was true. Male chickens had significantly higher feed intake (FI), BW gain, and FCR compared with females. A significant interaction was found of stocking density and age for FI, BW gain, and FCR. Compared with LSD treatment, HSD broilers had a higher FI and a lower FCR from 36 to 42 d of age. Stocking density, sex, and age had a significant interaction for BW gain and FCR. Female broilers had worse BW gain and FCR when stocked at high density from 36 to 42 d of age. Stocking density had no significant influence on breast, thigh, or abdominal fat yield. Female broilers had significantly higher breast yield and abdominal fat. Male broilers and HSD treatment had high footpad burn and gait scores. A low ME diet increased footpad burn score but had no effect on gait score. The result indicated that stocking density had a more severe effect on the growth of male broilers before 35 d of age. Female broilers need more space than males at similar BW per square meter near marketing age. The incidence and severity of leg weakness are associated with sex, diet, and stocking density. This result suggests that the deteriorated effect of high stocking density is sex and age dependent.

The effects of royal jelly on performance and fatty acid profiles of different tissues in quail (Coturnix coturnix japonica) reared under high stocking density

“…Similar to the performance results in the present study, HSD was shown to cause decreased FI, FCR, and BW gain, resulting in deteriorated poultry growth performance and welfare (11,12). When the number of birds per unit of space increases, microclimate conditions around the birds deteriorate.…”

“…Increasing the bird number per unit of space (density) reduces housing, equipment, and labor costs. It is, however, well documented that chickens housed at high density grow more slowly and have higher mortality and lower production quality (12,13). On the other hand, RJ has an antioxidant effect that counteracts the lipid peroxidation caused by free radicals under different stress conditions (4).…”

Comparison between linear and nonlinear systems of feed formulation for broilers

“…Independently of housing density, there were no differences in the performance at 42 d of age of females fed the linear formulation diet, despite the 40% higher bird density. These results are different from the findings of Zuowei et al (2011), who showed that females housed at high density had poorer FCR and lower BW at 42 d of age. The lower BW of females (Kolling et al 2005) compared with males may explain why, in the case of females, increasing bird density and maintaining the same nutritional density did not affect performance.…”

Effects of Dietary Threonine Levels and Stocking Density on the Performance, Metabolic Status and Immunity of Broiler Chickens

“…Our findings are in agreement with others related to lysine and ME. Zuowei et al (2011a) reported that lysine requirement of broilers is not altered by stocking density. In addition, Zuowei et al (2011b) reported that no significant interaction between the diet ME level and the stocking density, suggesting that the ME requirement was not changed by the stocking density.…”