Breed and heterosis effects on reproduction and production traits of Girolando cows

Abstract

Breeding and geneticsFull-length research article Breed and heterosis effects on reproduction and production traits of Girolando cows ABSTRACT -The objective of this study was to evaluate the breed and heterosis effects on reproductive traits, test-day milk yield, and 305-day milk yield in different lactations of crossbred Girolando cows. Data consisted of test-day milk yield records of first (118,831 records), second (63,227), and third lactation (44,512) and their relative productive (test-day milk yield, 305-day milk yield, and lactation length) and reproductive (age at first calving, calving interval, days open, and dry period) records of 35,582 Girolando cows from Brazil, collected from 1998 to 2014. The heterosis effect of the evaluated traits in Girolando cattle was estimated by MIXED procedure in SAS. Girolando cows showed a negative (favorable) and significant heterosis effect for reproductive traits. The dry periods between the first and second calving and between the second and third calving showed the greatest gains in heterosis (21.93 and 10.41%, respectively). All the evaluated productive traits showed a significant and similar heterosis effect between the three lactations. The use of crossbreeding strategies between the Holstein and Gyr breeds, instead of using the pure breed, is indeed a good alternative to increase the economic efficiency of the dairy activity in the different production systems in tropical environments.

Lifetime milk production of Holstein cattle in the humid tropics compared to Holstein‐Gyr and Holstein‐Brahman crosses

“…Vieira et al. (2022) also found the lowest AFC means in cows with a greater proportion of Holstein, such as those belonging to the genetic groups pure Holstein (HO), 7/8HO1/8GYR, 5/8HO3/8GYR, 3/4HO1/4GYR, and 1/2HO1/2GYR, compared to 3/8HO5/8GYR, 1/4HO3/4GYR, and pure Gyr (GYR).…”

“…Vieira et al. (2022) also reported a favourable, though much lower, heterosis effect for days open, with 6% (−9 days) and 10% (−13 days) for first and second lactation HO × GY cows, respectively.…”

“…It is known that dual-purpose cattle, normally associated with crossbreeding practices, generally take longer to reach the trait AFC (Reis et al, 2020). Vieira et al (2022) also found the lowest AFC means in cows with a greater proportion of Holstein, such as those belonging to the genetic groups pure Holstein (HO), 7/8HO1/8GYR, 5/8HO3/8GYR, 3/4HO1/4GYR, and 1/2HO1/2GYR, compared to 3/8HO5/8GYR, 1/4HO3/4GYR, and pure Gyr (GYR).…”

“…Higher values of AFC were found for purebred Brahman and Gyr compared to Holstein. The heritability of AFC is generally reported as low, indicating that the management system greatly influences this trait and depends more on the breeders' decisions than on the animal's physiology (Vieira et al., 2022). However, there is substantial evidence that certain breeds, particularly Bos taurus , tend to have their first calving much earlier than Bos indicus (Galina & Arthur, 1989).…”

“…GY × HO was equivalent to 120 kg more milk per lactation than the parental average. A meta-analysis byBunning et al (2019) on 89 crossbreeding schemes using tropical cattle reported an average heterosis effect of 35% for production traits Vieira et al (2022). found a 20% heterosis for milk yield in F1 HO × GY, equivalent to 976 kg per lactation above the parental average.…”