Wet feed and chilled water as stratigies to ameliorate heat stress impacts in growing turkeys during summer conditions.

The researchers investigated wet feed and chilled water effects on growth performance, carcass characteristics, and physiologic responses of native turkeys during the summer season. We hypothesized that the present treatments during the hot season would show different performances. A total of 180 four-week-old unsexed pullets were divided into six groups in a 3 × 2 factorial arrangement. Pullets were allocated regarding feed conditions to 3 groups (ad libitum dry feed, ad libitum wet feed, and diurnal wet feed). Each group was divided into 2 subgroups according to water temperature (ordinary or chilled water; 15-16 °C). Pullets fed diurnal wet feed and drank chilled water had the highest daily feed intake and the lowest feed conversion ratio during 4-16 weeks of age. Abdominal fat, IgG level and body temperature were low, whereas total antioxidant capacity and the meat quality scores for color, juiciness, and susceptibility were high in turkeys that drank chilled water. The interaction between wet feed and water temperature showed significant changes in glucose, cholesterol levels, and alanine transaminase activity. Pullets fed diurnal wet feed and drank chilled water had the lowest body temperatures. Wet feeding and chilled water may be the appropriate feeding method for native turkeys raised in hot weather.

Intermittent light program impacts on reproductive performance, health and welfare of breeding hens.

The lighting regime significantly impacts poultry production, reproductive performance, health and welfare. This study aimed to test the effect of the intermittent light (IL) regime on reproductive organs and hormones, semen quality, and behavioral performance. Thus, 270 Rhode Island Red hens aged 20 weeks were distributed among three groups of six replicates and 15 birds each, housed in floor pens. The first group was used as a control (C) and was exposed to constant light for 16 h d-1, while birds in other groups were exposed to IL for 20 min h-1 (T20) and 40 min h-1 (T40) during the 16 h light period. The outcomes were that follicle number was higher for T20 compared to T40 but not the controls, while T40 is different from T20 but not the controls. The same is true for testosterone. The sperm concentration is lower for T40 compared to the controls, with no difference between T20 and the controls. Body temperature was not different among groups. Conversely, differences were not noticed for leg alterations; plumage conditions; and relative ovary, oviduct, and/or testes weight and hatchability. Thus, the IL T20 program should be further investigated as a lighting regimen for managing Rhode Island Red laying hens for stimulating follicle number and testosterone without negatively impacting the physiological response and health traits. From a practical point of view, the IL schedule of 20 min h-1 during 20-36 weeks of age can be economically viable due to saving 66 % of the light cost.

Early heat acclimation during incubation improves Japanese quail performance under summer conditions.

Effects of exposing quail eggs to high temperature on the heat tolerance ability and productivity of birds were investigated. Four groups of 600 fertile eggs were randomly selected; the first group was incubated under 37.5 °C and the hatched chicks were reared under a gradual decrease in temperature from 35 to 24 °C (Control). The second group was exposed to 39.1 °C for 2 h/day during 4-14 days of embryogenesis and the hatched chicks were reared under a gradual decrease in temperature from 35 to 24 °C. The third group was incubated under 37.5 °C and the hatched chicks were exposed to 39 ± 1 °C for 2 h/day during 4-14 days of age. The fourth group was exposed to 39 ± 1 °C for 2 h during 4-14 days of embryogenesis and the hatched chicks were exposed to 39 ± 1 °C for 2 h/day during 4-14 days of age. The temperature applied changed (P < 0.01) embryo weight and incubation period. Birds exposed to high temperature during brooding had superior growth performance, dressed carcass, body temperature and health traits. Birds subjected to 39 ± 1 °C during brooding exhibited decreased feed consumption and body weight gain. Finally, this work suggests that thermal acclimation during embryogenesis might offer a practical method for easing heat stress.