With the aim to find indirect parameters for meat production that potentially could be used for selective purposes in Cornigliese sheep breed, 368 animals were weighed and measured (16 linear measures) during two years in 4 flocks with pasture and open range management from spring to autumn and closed facilities during winter. An amount of 0.2–0.4 kg/head/day of the same concentrate was provided to growing lambs from weaning to slaughter and to lactating ewes. Thirteen morphologic indexes were then calculated from body weight (BW) and linear measures. Analysis of variance on the basis of general linear model procedure was conducted with sex, age-class, year of birth, flock, type of lambing and interaction of sex*age-class as fixed factors and individual as a random factor. The allometric function was applied to body measures and indexes in relation to BW. A positive allometry was recorded for croup width between the trochanters (CrW1: 0.381), at ileum (CrW2: 0.452) and at ischium (CrW3: 0.615), indicating that this region has the fastest growth in relation to BW. All other body measures showed isometry or negative allometry, indicating a slower development in relation to BW. The lowest common allometric coefficient was recorded for front shank circumference (FSC) (0.131) followed by head width (0.200). Among indexes, the lowest growth was recorded by dactyl-thoracic index, due to the slow development of FSC. Sex related differences in allometric coefficients were noted for height at withers and head length (P < 0.05), FSC and forehead width (P < 0.01) with males earlier than females, and for chest width, chest depth, CrW1 (P < 0.05), CrW3 and ear width (P < 0.01) with females earlier than males. In conclusion the study of the allometric function applied to body measures and indexes was able to assess the importance of the croup width, not only in females (functional to an early and easy lambing) but also in males (functional to meat production).
Allometric coefficients for body measures and morphometric indexes in a meat-type sheep breed / Sabbioni, Alberto; Beretti, Valentino; Righi, Federico; Superchi, Paola. - In: SMALL RUMINANT RESEARCH. - ISSN 0921-4488. - 144:(2016), pp. 248-254. [10.1016/j.smallrumres.2016.10.005]
Allometric coefficients for body measures and morphometric indexes in a meat-type sheep breed
SABBIONI, Alberto;BERETTI, Valentino;RIGHI, Federico;SUPERCHI, Paola
2016-01-01
Abstract
With the aim to find indirect parameters for meat production that potentially could be used for selective purposes in Cornigliese sheep breed, 368 animals were weighed and measured (16 linear measures) during two years in 4 flocks with pasture and open range management from spring to autumn and closed facilities during winter. An amount of 0.2–0.4 kg/head/day of the same concentrate was provided to growing lambs from weaning to slaughter and to lactating ewes. Thirteen morphologic indexes were then calculated from body weight (BW) and linear measures. Analysis of variance on the basis of general linear model procedure was conducted with sex, age-class, year of birth, flock, type of lambing and interaction of sex*age-class as fixed factors and individual as a random factor. The allometric function was applied to body measures and indexes in relation to BW. A positive allometry was recorded for croup width between the trochanters (CrW1: 0.381), at ileum (CrW2: 0.452) and at ischium (CrW3: 0.615), indicating that this region has the fastest growth in relation to BW. All other body measures showed isometry or negative allometry, indicating a slower development in relation to BW. The lowest common allometric coefficient was recorded for front shank circumference (FSC) (0.131) followed by head width (0.200). Among indexes, the lowest growth was recorded by dactyl-thoracic index, due to the slow development of FSC. Sex related differences in allometric coefficients were noted for height at withers and head length (P < 0.05), FSC and forehead width (P < 0.01) with males earlier than females, and for chest width, chest depth, CrW1 (P < 0.05), CrW3 and ear width (P < 0.01) with females earlier than males. In conclusion the study of the allometric function applied to body measures and indexes was able to assess the importance of the croup width, not only in females (functional to an early and easy lambing) but also in males (functional to meat production).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
