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Background: In the commercial hatchery, broiler chicks are hatched over a wide time window, sometimes of up to 36 hours. More time is lost to get the chicks to the farms, so that overall, it may take up to three days for chicks to have access to feed or water. The chicks lose weight and may not recover enough to achieve their maximum potential growth. Chicks could benefit from early access to feed and water. The objective of the study was to assess the loss in weight as a result of feed and water deprivation over 36 hours and to evaluate the suitability of some substrates for early-feeding of broiler chicks. Design: In the first of two experiments, broiler chicks were either provided access to feed and water within 8 hours of hatch or held for 36 hours before gaining access. The birds were also fed on a commercial diet or a similar diet supplemented with palatinose or trehalose at the rate of 10 g/kg. In experiment 2, the two carbohydrate sources (10 or 20 g/kg diet) were further compared with an antibiotic, zinc-bacitracin (50 ppm). The diets were fed for 21 days, followed by assessment of gross response, nutrient digestibility, development of the intestinal mucosa and activities of intestinal and pancreatic enzymes. Outcomes: Holding chicks resulted in weight loss of up to 11 %. In experiment 1, feed intake was significantly increased (P<0.001) as a result of early access to feed. The 21d live weight of birds was improved (P<0.001) through supplementation with trehalose but not palatinose. In experiment 2, feed intake was similarly improved (P<0.01) and birds on the trehalose-supplemented diet were up to 7% heavier than the control birds but this was not significant. There were no significant differences between the groups in the other variables that were assessed. Conclusions: Trehalose may hold some promise as an early-feeding supplement for broiler chickens, but this would require further investigations. |
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