Effects of early feed restriction programs on production performance and hormone level in plasma of broiler chickens

Abstract

Age, duration and intensity of feed restriction of broiler chickens were studied by L 9 (3 4 ) orthogonal experiment. Broiler production performance and meat color were measured to evaluate the effects of feed restriction and explore the superior FR program. A total of 250 1-day-old Ross 308 chicks were selected and randomly allocated to ten groups, including one feed ad libitum (AL) group and nine feed restriction (FR) groups; each group had 5 pens with 5 chickens each. Broilers (T 5 D 7 I 90 ), feed-restricted to 90% from day 5 to day 11, had the highest body weight (BW), carcass weight, eviscerated weight, leg muscle weight and breast muscle weight, as well as muscle ratio. While broilers (T 5 D 14 I 70 ), feed-restricted to 70% from day 5 to day 18, had the lowest. Triiodothyronine (T 3 ) and growth hormone (GH) decreased while thyroxine (T 4 ) and the ratio of T 4 /T 3 increased in FR broilers. Feed conversion ratio, abdominal fat ratio, whole eviscerated weight ratio and lightness (L*) and yellow/blue (b*) value of leg muscle color increased in FR broilers (P> 0.05). T 5 D 14 I 70 had the lowest red/green (a*) color value of leg muscle and the highest L* and b* color values of breast muscle (P> 0.05). FR groups except T 10 D 14 I 90 had lower a* color value of breast muscle than AL. FR program of T 5 D 7 I 90 resulted in superior production performance and higher capability of meat production. Broilers feedrestricted T 5 D 14 I 70 were stunted with the lowest muscle growth capability and deteriorated in the breast muscle color. FR improved leg muscle color and increased broiler byproduct production. Lower T 3 and GH concentration and higher T 4 /T 3 ratio in plasma were related with the increased feed conversion rate and fat deposition in FR broilers; however, they had no relation with meat production and growth rate.

Effects of chronic heat exposure on growth performance, intestinal epithelial histology, appetite‐related hormones and genes expression in broilers

“…Given the shared response in some measures of the HS and PF groups, the PF treatment as a model of chronic feed restriction may be challenged with nutrients deficiency, resulting in a physiological stress. It has been reported that feed restriction treatment increased the plasma corticosterone concentration just like heat stress …”

“…It has been reported that feed restriction treatment increased the plasma corticosterone concentration just like heat stress. 53,54…”

Feed Restriction Induced Changes in Behavior, Corticosterone, and Microbial Programming in Slow- and Fast-Growing Chicken Breeds

“…The treatments were slow-growing Weining chickens fed ad libitum (SA, n = 50) or under feed restriction (SR, n = 50), as well as fast-growing Jinling chickens fed ad libitum (FA, n = 50) or under feed restriction (FR, n = 50). Feed-restricted birds were restricted from the age of 30 days to 60 days at a level of 70% of the intake of control birds of the same breed [ 14 ]). The ad libitum feed restriction measures were estimated based on our previous study using the same breeds under cage rearing [ 26 ].…”

“…The duration, intensity, and timing of feed restriction each have an impact on the growth of chickens [ 13 ]. For example, mild feed restriction of broilers to 90% ad libitum intake for 7 days during early life resulted in the highest body weight, while restriction to 70% for 14 days caused the lowest body weight compared to birds fed ad libitum [ 14 ]. The benefits of alternative feed restriction for chickens are controversial: some authors argue that feed restriction of broilers is commonly applied to promote animal health and decrease feed costs, and thus improve animal welfare [ 15 ].…”

“…Others argue that “metabolic hunger” exists even though restrictions promote satiety and achieve production performance [ 16 ]. Besides, the timing of appropriate feed restriction in early life is conducive to the metabolic programming and physiological process in the late stage of broilers [ 14 , 17 ]. The early adaptation to nutritional stress can adjust and prepare an organism for acclimation in broilers [ 18 ], although this has rarely been studied in the slow-growing local breed.…”