Effects of heat stress on pullet cloacal and body temperature.

One measure of the thermal status of poultry is cloacal temperature measured with a cloacal thermometer; however, this method requires handling the bird, is invasive, and can be stressful. Infrared thermography is an alternative means for assessing bird thermal status. The objective of this study was to investigate the body temperature response of pullets subjected to different environmental air temperatures during the growing phase and to evaluate the relationship between the cloacal temperature and the body parts surface temperature. A total of 648 chicks (Lohmann LSL Lite) were used in 2 different phases, phase I (day 1 through 6 wk of age) and phase II (week 7 through 17). During phase I, chicks were reared at 1 of 3 different thermal environments: thermal comfort (35°C-19°C), mild heat stress (38°C-22°C), or mild cold stress (28°C-17°C). In phase II, pullets were randomly redistributed to 1 of 4 daytime temperature treatments: 20°C; 25°C; 30°C; and 35°C, all with night time temperature of 20°C. Cloacal temperature and body surface temperature for 8 parts (head, eye, comb, chest, back, wing, leg, head area, and body area) were obtained weekly from 4 to 2 birds per treatment, respectively, during phase II. There were no effects for the interactions between the 2 experimental phases for cloacal and body parts surface temperature. There was a strong correlation (P < 0.001) between cloacal temperature and each body part temperature; cloacal temperature followed a quadratic response to environmental air temperature treatments. Pullets subjected to 35°C/20°C and 30°C/20°C had the highest body parts temperatures compared with the other 2 treatments (P < 0.05). The leg surface temperature was greatest in all treatments, and the chest the lowest. Regression between cloacal and body parts temperature had a 95% predictive accuracy of better than 0.4°C, suggesting a useful alternative to direct cloacal temperature measurement.

Productive performance and surface temperatures of Japanese quail exposed to different environment conditions at start of lay.

The objective of this study was to evaluate the effects of different environment conditions on productive performance and surface temperatures of Japanese quail (Coturnix coturnix japonica) during the initial stage of laying. In environmental controlled chambers, the birds were subjected to different temperatures and air velocities at the feeder. A total of 216 Japanese quails were distributed randomly in 2 galvanized wire cages, with 3 partitions each and 27 birds/cage. The experimental design consisted of randomized blocks with 2 treatments (air velocity at the feeder: 0, 1, 2, and 3 m/s and air temperature: 17, 23, 29, and 35°C) and 6 replicates. The productive performance was analyzed statistically (Sigma Plot 12.0) by 2-way ANOVA, with treatment means separated by the Tukey test (P < 0.05). To evaluate the main effects and interactions of the factors, the Holm-Sidak multiple comparisons test was performed using a mild condition as the control group (0 m/s). Feed intake did not differ (P > 0.05) among birds reared at temperatures of 23, 29, and 35°C, but higher feed intake was noted at 17°C. The mean values of egg production increased significantly (P < 0.05) with increased air velocity levels. It was observed that there was an increase in egg production and feed intake with the intensification of air velocity at the feeder, regardless of ambient temperature. Egg weight and feed conversion were not affected by air velocity treatments (P > 0.05). There was a significant positive correlation between air temperature and mean surface temperature and head surface temperature. In contrast, a significant negative correlation was observed between air velocity and mean surface temperature and head surface temperature. Productive performance was affected by temperature and air velocity, except for egg weight and feed conversion, which was not influenced by air velocity. Air velocity is important in removing heat from the surface of birds.

Effects of carbon dioxide on turkey poult performance and behavior.

Appropriate ventilation of poultry facilities is critical for achieving optimum performance. Ventilation promotes good air exchange to remove harmful gases, excessive heat, moisture, and particulate matter. In a turkey brooder barn, carbon dioxide (CO2) may be present at higher levels during the winter due to reduced ventilation rates to maintain high temperatures. This higher CO2 may negatively affect turkey poult performance. Therefore, the objective of this study was to evaluate the effects of subjecting tom turkey poults (commercial Large White Hybrid Converters) to different constant levels of atmospheric CO2 on their growth performance and behavior. In three consecutive replicate trials, a total of 552 poults were weighed post-hatch and randomly placed in 3 environmental control chambers, with 60 (Trial 1) and 62 (Trials 2 and 3) poults housed per chamber. They were reared with standard temperature and humidity levels for 3 wks. The poults were exposed to 3 different fixed CO2 concentrations of 2,000, 4,000, and 6,000 ppm throughout each trial. Following each trial (replicate), the CO2 treatments were switched and assigned to a different chamber in order to expose each treatment to each chamber. At the end of each trial, all poults were sent to a local turkey producer to finish growout. For each trial, individual body weight and group feed intake were measured, and mortality and behavioral movement were recorded. Wk 3 and cumulative body weight gain of poults housed at 2,000 ppm CO2 was greater (P < 0.05) than those exposed to 4,000 and 6,000 ppm CO2. Feed intake and feed conversion were unaffected by the different CO2 concentrations. No significant difference in poult mortality was found between treatments. In addition, no effect of CO2 treatments was evident in the incidence of spontaneous turkey cardiomyopathy for turkeys processed at 19 wk of age. Poults housed at the lower CO2 level (2,000 ppm) demonstrated reduced movement compared with those exposed to the 2 higher CO2 concentrations.