The Effect of Cyclic and Constant Ambient Temperatures on Feed Consumption, Egg Production, Egg Weight, and Shell Thickness of Hens

Abstract

Groups of 18 hens, 230 days of age, were housed in each of three climatic chambers with light schedules of 14L:10D. One was maintained at a constant temperature of 23.9 C, the second was cycled between 15.6 and 37.7 C (mean, 26.7 C), and the third was cycled between 21.1 and 37.7 C (mean, 29.4 C). In Experiment 1, the high temperature peaked during the dark period at 0200 hr and in Experiment 2, the high temperature peak was at 1400 hr during the light period. The birds had free access to a commercial breeder feed in these two experiments. The results from three 2-week observation periods indicated no significant differences in percent hen-day production, grams of feed per gram of egg mass, or overall body weight change but feed intake per day, egg weight, and shell thickness were significantly reduced by mean temperatures of 26.7 and 29.4 C in cycling chambers. The pair-feeding of birds in the 23.9 C constant chamber compared with those in the cycling 29.4 C chamber resulted in production of significantly heavier eggs with thicker shells without significantly influencing any of the other parameters. The reductions in egg weight and shell thickness observed at cyclic temperatures were not simply a result of a reduction in nutrient intake at high temperatures but also the direct effect of heat stress on the hens. In the 23.9 C constant temperature chambers, a reduction in AME of the feed for the hens fed ad libitum was observed but not for hens pair-fed to hens in the 29.4 C cyclic chamber.

Effects of feed supplementation with manganese from its different sources on performance and egg parameters of laying hens

“…The minimum requirement for the maximal eggshell quality was found to be 50-100 mg/kg. Our overall results show that sup- Eggshell breakage is known to be directly related to the quality of the shell, which can be affected by nutrition and breeding conditions (Emery et al, 1984;Tůmová et al, 2009). It is well established that trace elements may affect eggshell quality by their catalytic properties as key enzymes involved in the process of membrane and eggshell formation, or by interaction directly with the calcite crystals in the formation of eggshells (Zamani et al, 2005).…”

Physiological Responses of Slow-Growing Chickens under Diurnally Cycling Temperature in a Hot Environment

“…Decreases in BW gain were recorded in broilers exposed to temperatures of 31 to 36°C and 28 to 36ºC (QuinteiroFilho et al, 2010). Furthermore, Emery et al (1984) showed that laying hens under cycling temperatures, ranging between 21.1 to 37.7°C, lost more BW than birds at a constant temperature of 23.9°C, which was largely attributed to reduced feed consumption.…”

Effects of Heat Stress on the Daily Behavior of Wenchang Chickens

“…For instance, Gao et al (1999) reported that, when external house temperature was high, broiler feed intake, feed conversion ratio, and growth rate were reduced. In heat-stressed layers, reduced food intake led to a decrease in egg production and reduced egg weight and quality (Emery et al, 1984).…”