Effects of birth type and family on the variation of carcass and meat traits in Santa Ines sheep.

This study aimed to evaluate the effects of birth type and family on quantitative and qualitative meat traits in Santa Ines lambs and to do a descriptive study of variation inside of breed. A total of 50 carcass and meat traits were evaluated in up to 101 lambs slaughtered at 424 days of age. Random effect of family, the fixed effect of birth type (single or double) and year, and the covariates of dam's weight at weaning and age (in days) at slaughter were inserted in the model. This study shows that some carcass and meat traits in Santa Ines raised on pasture has large variability, specially for meat cut yields, several carcass non-components yields, and rib eye area, subcutaneous fat thickness, shear force, cooking losses, and b* color parameter. The birth type effect influenced (P < 0.05) rump width; reticulum, leg, heart and kidney yields; and the carcass pH at 24 h after slaughter. The family effect was significant (P < 0.05) for cold carcass weight; hot, cold and true carcass yields; external carcass and leg lengths; perimeter and width of the rump; kidney, liver and tail yields; and carcass pH at slaughter.

Variants in GH, IGF1, and LEP genes associated with body traits in Santa Inês sheep

Growth hormone (GH), insulin-like growth factor 1 (IGF1), and leptin (LEP) can be candidate genes for association studies because they play vital roles in the metabolism process. Thus, this study aimed to identify variants in these genes associated with body traits in Santa Inês sheep. The following were recorded: body weight at 100 (BW100) and 240 days (BW240), average daily gain (ADG), withers (WH) and croup (CH) heights, body length (BL), thoracic (TG) and leg (LG) girths, thoracic (TW) and croup (CW) widths, body depth (BD), rib eye area (REA), fat thickness (FT), and carcass finishing score (CFS). Single-locus association analysis was performed with 11 variants in IGF1, 18 in LEP, and 16 in GH. Moreover, two haplotypes in IGF1 and one haplotype in LEP were evaluated in haplotype association analysis. The single-locus analysis revealed 23 suggestive additive effects (p < 0.05), but no additive effect was found at the Bonferroni threshold. Haplotype association analysis revealed 19 additive effects, of which ten were at the Bonferroni threshold (p < 0.0074). In IGF1 gene, haplotype replacements were associated with ADG 20.51(7.37), CH 4.09(1.21), WH 3.52(1.20), BL 3.94(1.19), TG 3.88(1.30), TW 1.13(0.36), and LG 3.40(1.08); while in the LEP gene the haplotype replacement was associated with BW100 1.83(0.51), BD −2.51(0.56), and CFS −0.24(0.06). Therefore, there are haplotypes in IGF1 and LEP genes associated with body traits in Santa Inês sheep, which can be useful in marker-assisted selection.

Variants in GH, IGF1, and LEP genes associated with body traits in Santa Inês sheep

Growth hormone (GH), insulin-like growth factor 1 (IGF1), and leptin (LEP) can be candidate genes for association studies because they play vital roles in the metabolism process. Thus, this study aimed to identify variants in these genes associated with body traits in Santa Inês sheep. The following were recorded: body weight at 100 (BW100) and 240 days (BW240), average daily gain (ADG), withers (WH) and croup (CH) heights, body length (BL), thoracic (TG) and leg (LG) girths, thoracic (TW) and croup (CW) widths, body depth (BD), rib eye area (REA), fat thickness (FT), and carcass finishing score (CFS). Single-locus association analysis was performed with 11 variants in IGF1, 18 in LEP, and 16 in GH. Moreover, two haplotypes in IGF1 and one haplotype in LEP were evaluated in haplotype association analysis. The single-locus analysis revealed 23 suggestive additive effects (p < 0.05), but no additive effect was found at the Bonferroni threshold. Haplotype association analysis revealed 19 additive effects, of which ten were at the Bonferroni threshold (p < 0.0074). In IGF1 gene, haplotype replacements were associated with ADG 20.51(7.37), CH 4.09(1.21), WH 3.52(1.20), BL 3.94(1.19), TG 3.88(1.30), TW 1.13(0.36), and LG 3.40(1.08); while in the LEP gene the haplotype replacement was associated with BW100 1.83(0.51), BD −2.51(0.56), and CFS −0.24(0.06). Therefore, there are haplotypes in IGF1 and LEP genes associated with body traits in Santa Inês sheep, which can be useful in marker-assisted selection.(AU)

Avaliação Ultra-Sonográfica dos Testículos e das Glândulas Sexuais Acessórias de Ovinos da Raça Santa Inês

Com o desenvolvimento da caprino-ovinocultura tornou-se necessário o increemento de biotecnologias nestas criações. Pesquisas ultra-sonográficas do sistema genital masculino têm sido realizadas, em especial nos bovinos e equinos. Devido à escassez de informações do uso da ultra-sonografia no exame clínico de ovinos, o presente estudo avaliou 49 ovinos da raça Santa Inês através de exames andrológicos e de imagens ultra-sonográficas dos testículos e das glândulas sexuais acessórias, objetivando a demonstração desta técnica como um recurso diagnóstico complementar à avaliação desta espécie. Os animais foram divididos em três grupos de acordo com a faixa etária, sendo o grupo I (GI), composto por 20 animais de 18 meses e peso vivo (PV) médio de 50,64Kg+/- 3,81, o GII por 15 animais de 30 meses e PV de 59,80 Kg+/-3,96, e o GIII por 14 animais de 48 meses de idade e PV de 102,57 Kg+/-4,13Kg. As mensurações testiculares foram realizadas nos três grupos etários, avaliando-se as médias da circunferência escrotal (G I 30,17+/- 0,59; GII 32,21+/-0,55; GIII 34,57+/-2,05), do comprimento (GI 7,38 cm +/- 0,20; GII 8,27cm+/-0,19; GIII 8,66cm+/-0,82) , da largura (GI 3,03cm+/-0,06; GII 3,15cm+/-0,05; GIII 4,37cm+/-1,29), do volume (GI 141,29cm3+/-6,71; GII 165,02cm3+/-6,16; GIII 238,14cm3+/-7,29) e da forma (GI 0,41cm+/-0,01;GII 0,38cm+/-0,01; GIII 0,51cm+/-0,15) testiculares. O sêmen colhido através da eletroejaculação, foi analisado de acordo com o CBRA (1998), não apresentando diferenças significativas (p>0,05) entre os grupos GI, GII e GIII. As avaliações ultra-sonográficas foram iniciadas durante a pré-ejaculação pela análise da ecogenicidade do parênquima testicular, observando-se imagens hipoecogênicas de baixa e alta intensidade. As calcificações nos testículos direito e esquerdo forma observadas nos grupos GI, GII e GIII, nos graus leve, moderado e severo. A calcificação testicular do tipo leve foi observada com maior frequência independentemente da faixa etária (GI,GII e GIII) o mediastino testicular foi classificado em difuso, moderado e altamente ecogênico. As glândulas bulborretais e vesiculares foram mensuradas e ecogenicamente analisadas, durante as fases de pré e pós-ejaculação. A ecotextura predominante das glândulas bulborretais e vesiculares na pré-ejaculação foi hipoecóica de baixa intensidade. Esta pesquisa demosntrou a importância da utilização da ultra-sonografia para a avaliação clínica de ovinos, aliada aos resultados dos exames andrológicos, para a escolha de futuros reprodutores potencialmente superiores