Evaluation of genotype by environment interactions on milk production traits of Holstein cows in Southern Brazil

Abstract

A slight change in genotype between areas was expected since no significant genotype by environment interactions were identified, facilitating the process of selecting Holstein cattle in southern Brazil.

Genotype by environment interaction for fat and protein yieldsviareaction norms in Holstein cattle of southern Brazil

“…Relevant FY (277.81 kg/lactation/year) and PY (255.47 kg/lactation/year) were observed among the studied herds. Similar values have been reported by Moreira et al (2018) for herds in southern Brazil. High volumes of milk solids from Holstein cattle are delivered to milk processing plants to produce milk derivatives in southern Brazil.…”

“…We observed that FY heritability was always moderate, varying from 0.21 to 0.27, reinforcing the absence of GEI. Similar heritability estimates have been reported by Moreira et al (2018) and Paula et al (2008) for Holstein herds in Brazil and by van der Laak et al (2016) for herds in Netherlands. However, higher FY heritability has been reported elsewhere for Holstein cattle.…”

“…Similar heritability estimates have been reported by Moreira et al . (2018) and Paula et al . (2008) for Holstein herds in Brazil and by van der Laak et al .…”

“…Similar values have been reported by Moreira et al . (2018) for herds in southern Brazil. High volumes of milk solids from Holstein cattle are delivered to milk processing plants to produce milk derivatives in southern Brazil.…”

“…Environmental factors such as temperature are widely known to have detectable effects on milk production and composition (Komisarek and Kolenda, 2016; Pragna et al ., 2017). However, climate variations have not been considered in genetic evaluation studies performed in southern Brazil (Moreira et al ., 2018). Not considering GEI might lead to a bias in the genetic value of the data resulting in differences in the expected selection response (Streit et al ., 2012).…”