Effect of Early Nutrient Restriction on Broiler Chickens.

Abstract

An experiment was conducted to determine the effect of two early nutrient restriction programs on performance, selected characteristics of the gastrointestinal tract (GIT), and activities of digestive enzymes of broiler chickens. Three hundred and sixty male broiler (Ross x Ross) chicks kept in floor pens were assigned to three groups. The control group (C) was given ad libitum access to feed from 1 to 48 d of age. Another group was restricted from 11 to 14 d (R4) of age to an energy intake of .74 x BW.67 kcal ME/d, and a third group was restricted from 7 to 14 d (R7) of age to an energy intake of 1.5 x BW.67 kcal ME/d. Then, both restricted groups were given ad libitum access to feed through 48 d. Body weight and feed intake were determined weekly and selected carcass characteristics were measured at 48 d of age. Broilers also were sampled at 7, 14, 21, and 42 d of age to obtain data on components of the GIT (proventriculus, gizzard, pancreas, and small intestine) and activities of selected digestive enzymes. Feed-restricted groups were lighter in body weight (P < .01) at 14 and 48 d of age than the C group but were superior in overall feed efficiency. No treatment effects were observed for percentage yields of breast meat and abdominal fat pad. Absolute weights of GIT components were significantly reduced at 14 d of age by feed restriction. However, GIT components increased in weight more quickly after refeeding than did the whole body. Restricted groups had reduced (P < .01) specific activities of jejunal alkaline phosphatase and pancreatic trypsin, amylase, and lipase as compared with the C group at 14 d of age but not at 21 and 42 d of age. Relative activities for jejunal maltase and sucrase were greater (P < .01) at 21 d of age in the R4 and R7 groups than in the C group. The present data show that feed restriction results in transient changes in organs and activities of digestive enzymes, suggesting a functional adaptation to feed restriction.

Effects of meal-time feeding and protein restriction on walking ability and some bone and carcass properties in broilers

“…These observations support the findings of Palo et al (1995) who reported that carcass and breast yields were not affected in two early feed-restriction programs. Similarly, Dozier et al (2003) confirmed these findings.…”

Effects of quantitative feed restriction on the performance of broiler chickens

“…It has been known that feed restricted birds consumed more feed in their attempt to compensate for the time they would have been deprived of feed (Khetani et al, 2009). In contrast, Palo et al (1995) observed that feed restricted birds gained less weight than full-fed control birds. The possible explanation of the lower body weight observed in the feed restricted birds may be the decrease in The highest FCR in birds fed with control (T1) diet and the lowest FCR in birds fed with 70% diet (T4) could be due to significantly higher and lower feed intakes of birds, respectively.…”

Tracking the development of serum biochemical parameters in two laying hen strains – a comparative study

“…Alkaline phosphatase is a complex enzyme, related to secondary ossification, osteoblastic activity; moreover, it is produced in the intestinal brush border. In this regard PALO et al (1995) reported an activity peak in broilers at the age of 2 weeks, corresponding to the exhaustion of the yolk sac as well as to the establishment of locomotory independence. An early peak, and the latter continuous activity reduction was moreover described by SZABÓ et al (2005), along the entire rearing course of heavy weight turkeys.…”