Bone mineralization in male commercial broilers and its relationship to gait score

Abstract

Broilers selected for increased body size and breast muscle have imposed stress on the skeletal system, resulting in poorer walking ability. Our objectives were to determine the relationship between bone mineralization and gait score in 4 crosses of commercial broilers and to ascertain if mineralization of the toe is correlated to the tibia. Three chickens per pen each with good (gait score of 0 or 1) or poorer (gait score of 3) walking ability were killed and weighed. The left humerus, the left middle toe, and both drumsticks were collected for determination of bone mineral density (BMD), bone mineral content, and bone size traits using dual-energy x-ray absorptiometry. The BMD and bone size traits were similar among the 4 crosses of commercial broilers at 6 wk of age. However, gait scores differed among genotypes, with cross C having better gait scores than crosses A and B, but did not differ from cross D. The bone mineral content and bone size traits did not differ between birds with good walking ability as compared with those broilers of poorer walking ability. However, birds with poorer walking ability had higher BMD (P<0.05) and BW (P<0.001) than males with good walking ability. Within a cross, the correlation between gait score and BMD was not significant except for cross D birds. Broilers of cross D with better walking ability had decreased bone mineralization (r=0.19, P=0.03). The stronger correlation between gait score and BW for all crosses of commercial broilers (r=0.38, P<0.0001) suggests that the low association between gait score and bone mineralization for cross D was mainly due to BW. The BMD of the left toe was correlated to the BMD of the left tibia (r=0.91, P<0.0001) and right tibia (r=0.87, P<0.0001). In conclusion, bone mineralization was similar among crosses of meat-type chickens, and it had little influence on the gait score of male broilers.

Scientific Opinion on the influence of genetic parameters on the welfare and the resistance to stress of commercial broilers

“…Leterrier and Nys (1992) comparing tibial growth of slow and fast growing broilers showed that rate of growth was associated with lower mineral density and higher porosity of the tibial cortices (comparison at similar weights). On the other hand, the recent study of Talaty et al (2010) comparing four commercial broiler crosses shows that bone mineral density was similar between crosses. There is another report that shows that the bones of a fast-growing selected strain are more porous and less well mineralised than those of a slower-growing control strain (Williams et al, 2000).…”

Age- and Sex-related Differences of Morphometric, Densitometric and Geometric Parameters of Tibiotarsal Bone in Ross Broiler Chickens

“…The defects were also found in ostriches HOR-BAÑCZUK et al 2004). The problems with lower limb bones concern mainly males (CHARUTA et al 2012c;TALATY et al 2010).…”

Edible Giblets and Bone Mineral Characteristics of Two Slow-Growing Chicken Genotypes Reared in an Organic System

“…Bone breaking strength, bone ash concentration, and bone weight are positively correlated with BMD and BMC obtained by DXA in chickens (Fleming et al, 1994;Mazzuco and Hester, 2005;Kim et al, 2006Kim et al, , 2008. There is a strong correlation between BMD and BMC (r=0.81; p<0.01) in White Leghorns (Hester et al, 2004) as well in male broilers of commercial lines (Talaty et al, 2010). In addition, relatively larger bones present higher BMC correlation with total bone mineral content and are stronger and BMD and BMC values increase with broiler BW (Schreiweis et al, 2004).…”

“…BMD is a noninvasive method using dual-energy x-ray absorptiometry (DXA) that has also been employed to predict osteoporosis in humans (Bolotin, 2007;Koo, 2000). DXA could also be used to measure BMC in broilers and laying hens (Schreiweis et al, 2005;Shim et al, 2012;Talaty et al, 2010).…”