Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-4-16
pubmed:abstractText
Genetic selection has significantly improved the muscle development of fast-growing broiler chickens in the last 50 yr. However, improvement in muscle growth has coincided with relatively poor development of visceral systems, resulting in impaired ability to cope with high environmental temperatures. The aim of this study was to elucidate the effects of thermal manipulation (TM) during different periods of embryogenesis on chick hatchability, BW and thermoregulation upon hatching, on their ability to cope with thermal challenge at 42 d of age, and on carcass and breast meat traits. Control embryos were incubated at 37.8 degrees C. The TM embryos were incubated at 37.8 degrees C and treated for 3 h at 39.5 degrees C on the following days of embryogenesis: E8 to E10 [early (EA)], E16 to E18 [late (LA)], and both E8 to E10 and E16 to E18 (EA-LA). Body weight and body temperature (T(b)) were measured at hatching and throughout the growth period as well as during exposure of 42-d-old chickens to a thermal challenge at 35 degrees C for 6 h. The LA and EA chicks exhibited significantly lower T(b) than control chicks (37.9 vs. 38.2 degrees C) at hatching, but during the growth period, differences in T(b) between treated and control chicks decreased with age. Significant hyperthermia (over 44 degrees C) was monitored in all groups during the thermal challenge, but mortality was higher in treated than in control chickens. No effect of treatments on BW was found during the entire growth period. However, breast yield was higher in LA chickens than in controls at slaughter. The EA and EA-LA treatments slightly decreased the ultimate pH of breast meat, whereas the LA treatment had no effect. In conclusion, none of the TM conditions tested in the present study were able to improve long-term thermotolerance in chickens. Late treatment favored breast muscle growth without affecting ultimate pH and drip loss of breast meat.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0032-5791
pubmed:author
pubmed:issnType
Print
pubmed:volume
86
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
795-800
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Effects of thermal manipulation during early and late embryogenesis on thermotolerance and breast muscle characteristics in broiler chickens.
pubmed:affiliation
UR83 Recherches Avicoles, Institut National de la Recherche Agronomique, F-37380 Nouzilly, France. collin@tours.inra.fr
pubmed:publicationType
Journal Article, Controlled Clinical Trial