Genetic Parameter Estimates for Production and Reproduction Traits in Dairy Buffaloes

Abstract

-The objective of this study was to determine the genetic variation in milk production, milk components, and reproductive traits in dairy buffaloes. A total of 9,318 lactation records from 3,061 cows were used to estimate the heritability of milk yield (MY), fat percentage (%F), protein percentage (%P), lactation length (LL), calving interval (CI), and age at first calving (AFC), as well as genetic and phenotypic correlations between these traits. Covariance components were estimated by Bayesian inference in a multitrait animal model using the GIBBS2F90 program. Contemporary groups and number of milkings (1 or 2) were included as fixed effects, age of dam at calving (linear and quadratic effects) as a covariate, and additive genetic, permanent environmental, and residual effects as random effects. The heritability estimates (± standard deviation) were 0.24 ± 0.02, 0.34 ± 0.05, 0.40 ± 0.05, 0.09 ± 0.01, 0.05 ± 0.01, and 0.16 ± 0.04 for MY, %F, %P, LL, CI, and AFC, respectively. The genetic correlations between MY and %F, %P, LL, CI, and AFC were -0.29, -0.18, 0.66, 0.08, and 0.24, respectively. Milk production and milk components showed sufficient genetic variation to obtain genetic gains through selection. The genetic correlations between MY and milk components were negative, and thus, undesirable because efforts to increase MY may decrease milk quality. Reproductive traits had little genetic influence, indicating that improvement of management would be sufficient to obtain better performance.Keywords: Buffalo. Genetic correlation. Heritability. Milk yield. ESTIMATIVAS DE PARÂMETROS GENÉTICOS PARA CARACTERÍSTICAS DE PRODUÇÃO E REPRODUÇÃO EM BÚFALOS LEITEIROSRESUMO -Objetivou-se determinar a variação genética na produção de leite, seus constituintes e características reprodutivas. Foram utilizadas 9.318 lactações de 3.061 búfalas para estimar as herdabilidades das características produção de leite (PL), porcentagem de gordura (%G), porcentagem de proteína (%P), duração da lactação (DL), intervalo entre partos (IEP) e idade ao primeiro parto (IPP), além das correlações genéticas e fenotípicas entre as mesmas. Os componentes de covariância foram estimados por inferência Bayesiana em análises multicaracterísticas utilizando um modelo animal e o programa computacional GIBBS2F90. Foram incluídos os grupos de contemporâneos e o número de ordenhas (1 ou 2) como efeitos fixos, a idade da búfala ao parto (efeitos linear e quadrático) como covariáveis e os efeitos genético aditivo, ambiental e residual como efeitos aleatórios. As estimativas da herdabilidade e seus desvios-padrão para PL, % G, %P, DL, IEP e IPP foram 0,24±0,02; 0,34±0,05; 0,40±0,05; 0,09±0,01; 0,05±0,01 e 0,16±0,04, respectivamente. As correlações genéticas entre a PL e %G, %P, DL, IEP e IPP foram -0,29; -0,18; 0,66; 0,08 e 0,24, respectivamente. A produção de leite e seus constituintes apresentaram variação genética suficiente para obtenção de ganhos genéticos pela seleção. As correlações genéticas entre produção de leite e seus constituintes for...

Estimation of Genetic Parameters for Production and Reproduction Traits in Murrah Buffaloes

“…These results are in close agreement with the findings of Kumar et al, (2001) and Suresh et al, (2004). Higher and positive genetic correlation between LL and CI was supported by the findings of Barross et al, (2016) indicating that increase in LL will result in selection for longer CI. Tonhati et al, (2000b) and Aziz et al, (2001) found low genetic correlations between these traits (-0.20 and 0.09, respectively).…”

Detection of SNPs in Exon10 Locus of FSHR Gene and Their Association with Some Infertility problems in Egyptian Buffaloes

“…Similar to present results (Mourad and Khattab, 2009), (Ibrahim et al, 2012), (EL-Arian et al, 2012) and (Shalaby et al, 2013) recorded that high positive genetic correlation between days in milk and milk yield. The opposite results obtained by (Barros et al, 2016) reported that low negative correlation between days in milk and milk yield.…”

“…These results agreed with (Amin and Alhur, 2011) and (El-Bramony, 2014). The opposite results obtained by (Aziz et al, 2001), (Thevamanoharan et al, 2002), (Badran et al, 2005), (Kawthar et al, 2005), (El-Bramony, 2011), (Malhado et al, 2013) and (Barros et al, 2016) who recorded low heritability estimates for days open and calving interval.…”

Editing and modeling of milk production data for genetic evaluation of Murrah buffaloes

“…The number of buffaloes (Bubalus bubalis) have been increasing in the Brazilian livestock due to their rusticity, longevity, high adaptive capacity to adverse conditions (Joele et al, 2013;Barros et al, 2016;Santos et al, 2016) and resistance to diseases and endo and ectoparasites (Hurtago-Lugo et al, 2013).…”

“…However, dairy products from buffalo milk, such as yogurts, cheeses, ricotta and especially mozzarella, have reached high market values (Araújo et al, 2012;Barros et al, 2016). Therefore, the need for investments in sanitary, Pesq.…”