Location: Livestock Behavior ResearchTitle: Behavioral changes and feathering score in heat stressed broiler chickens fed diets containing different levels of propolis Author
|Cheng, Heng Wei|
Submitted to: Applied Animal Behaviour Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/6/2015
Publication Date: 3/19/2015
Citation: Mahmoud, U.T., Abdel-Rahman, M.A., Darwish, M.H., Applegate, T.J., Cheng, H. 2015. Behavioral changes and feathering score in heat stressed broiler chickens fed diets containing different levels of propolis. Applied Animal Behaviour Science. 166:98-105. DOI:10.1016/j.applanim.2015.03.003. Interpretive Summary: Recently with the rapid development of the poultry industry to meet food security and nutrition needs globally, the urgency to improve broiler stocks’ performance within hot regions is on the rise. Broiler performance is significantly reduced by heat stress. This phenomenon is becoming more severe as commercial broilers meet their genetic potential for high performance, leading to high susceptibility to heat exposure. Birds exposed to high environmental temperature conditions modify their behaviors and physiological homeostasis attempting to reduce body temperature. Propolis has recently become the subject of intensive pharmacological studies for improving human health. Similar to human research and clinical usage, propolis has been used as a diet supplement in poultry mainly as a growth promoter, immune-modulator and/or an antioxidant. This study aimed to determine the effect of propolis on behavioral exhibition and feather condition in Ross 708 broiler chickens following exposured to high environmental temperature from 15 to 42 days of age. The data indicated that propolis reduced heat stress associated behaviors and feather abnormalities. The results support that propolis may be used as a protective management practice in broiler chickens during hot season to alleviate the negative effects of heat stress. These results can be used by broiler chickens producer and scientists to develop management guidelines for improving broiler welfare.
Technical Abstract: This experiment was conducted to evaluate the effects of dietary supplementation of green Brazilian propolis on behavioral patterns and feather condition of heat stressed broiler chickens. Five hundred and four (504) male Ross 708 broiler chicks at 15-day old were randomly allotted to six dietary treatments containing 0 (control), 100, 250, 500, 1000 and 3000 mg kg-1 propolis powder, respectively. Each treatment consisted of four replicates of 21 birds each. Heat stress at 32 oC was applied daily from 08:00 am to 7:00 pm from day 15 to 42. 12 birds from each treatment were randomly taken and marked with livestock color for behavioral observation. Treatment effects on behavioral patterns were recorded using direct observation instantaneous scan sampling technique: 2 h per day for 3 days per week from day 15-42. The behaviors were categorized as a percentage of total activity performed during the observation time for the frequency of standing, walking, sitting, feeding, drinking, preening, and feather pecking. At the end of the experiment (42 days of age) the three birds used for behavioral observation were feather scored (from 1 to 5); while all birds (504) were individually scanned for primary feather abnormalities. The data were analyzed by using a two-way analysis of variance using the general linear models (GLM) followed by regression model procedure. The data indicated that propolis may be used as a feed additive for broilers to reduced heat stress associated behaviors, especially dietary treatment with 250 or 3000 mg kg-1 propolis (P < 0.05), by increasing bird mobility and reducing panting behaviors. While, 100 mg kg-1 propolis treatment only increased (P < 0.05) the standing activities of the birds. There were no significant (P > 0.05) treatment effects on sitting, preening, feeding, drinking, wing elevations and feather pecking activities. All propolis doses did not significantly (P > 0.05) improve feather scoring, but did reduce (P = 0.048) abnormalities in primary feathers. The behavioral improvement and reduced primary feather abnormalities reported here support that propolis treatment may be considered as a protective management practice in broiler chickens to partially alleviate the negative effects of heat stress, but it still needs further investigation to determine the best type, dose, time and duration of its administration.