A influência do escore de condição corporal, leptina e da grelina na reprodução de éguas: Revisão Bibliográfica

Abstract

Equine husbandry is the practice of breeding horses for companionship, agricultural work, sports, and genetic improvement for commercial purposes. Despite being a widely utilized species in agribusiness, reproduction has been underestimated throughout the domestication of the species due to its low fertility compared to other domesticated species. Feeding management has a significant influence on reproduction, as domestication has brought about various impacts on equine routines through physical exercise, confinement, and the use of different foods than natural ones. Nutrition is crucial for maintaining body condition, which affects the foaling rate, an index that measures the capacity of a female to produce offspring for sale or herd maintenance on a property. Body condition in the last third of gestation is important to ensure good embryonic development, colostrum production, and preparation for a new pregnancy after foaling. Poor body condition can impair contractions, foal weight, and the quality of colostrum produced. Excess weight can hinder foal delivery, leading to the birth of smaller foals with flexural deformities, and metabolic dysregulations that may be hereditary. One of the most commonly used tools to assess the metabolic status of equines is the body condition score, which indicates when the animal needs a reassessment of feeding management, especially if they are animals undergoing conception. Nutrition-related factors, such as the role of leptin in the hypothalamic-pituitary-gonadal axis and body condition score, are currently under research, aiming for reproductive success in the species. The objective of this work is, through literature review, to present the influence of nutrition on the reproduction of these females, seeking to understand the relationship between adequate nutrition and body condition in reproductive success. This work presents current discussions, leading to the conclusion that body condition score is directly related to nutrition, expressing bodily the effects of adequate or inadequate nutrition to which an equine is subjected. Inadequate nutrition reflects prolonged anestrous periods, increased embryonic losses, and impairs the growth of a healthy foal, preventing it from expressing its genetic potential. Therefore, understanding nutrition is one of the most important pillars for reproduction, and when associated with good breeding practices, zootechnical indices are favored, and the herd becomes productive.