Curva de crescimento em potros da raça Crioula do nascimento aos 24 meses de idade / Growth curve of Crioulo foals from birth until 24 months of age

ABSTRACT

Background: Breeding of Crioulo horses in the southern region of Brazil is very significant. Notwithstanding, not all animals meet the standards defined for the breed, raising concern among breeders, owners and veterinarians, driving them to an effort to know and understand the development of Crioulo foals. In order to get a registry at Brazilian Association of Crioulo Horse Breeders (ABCCC), the foals must be presented to a certified technician as of 24 months of age and show the breed standards and measurements required. To date, there are no data concerning development of this breed available. Therefore, this study aims to describe the growth curve of Crioulo foals in the south region of Rio Grande do Sul.Materials, Methods & Results: The study was conducted in three Crioulo horse breeding farms in the cities of Santa Vitória do Palmar, Bagé and Aceguá, in the state of Rio Grande do Sul, Brazil, for a period of two years (2013-2015). We followed up on 267 Crioulo foals from birth up to 24 months of age. Biometric evaluation was divided in 26 periods, with 40 animals in each and random repetition of individuals. Period one birth to seven days; period two seven to 21 days; monthly from 1st to 24th month. The three breeding farms presented similar environmental conditions and the horses were submitted to similar management. Measurements were taken on a monthly basis, using a mechanical scale for weight and a hippometer for height. The analysis were conducted on SAS/ETS® version 9.2. Logistic non-linear regression model was used to obtain growth curves for height and minimum, medium and maximum weight of the foals on their respective ages, by this way six growth curves were produced. Results show an increase in weight and height at 24 months of age compared to the moment of birth. This increase was accentuated during the first months of life, both in weight and height.[...]