Ultrasound evaluation of fetal parameters to estimate gestational age in native Teramana goats

Abstract

ABSTRACT Biodiversity, understood as biological variability, is based on genetic diversity and represents a heritage to be protected. The protection of species at risk of extinction aims to address the problems related to genetic impoverishment through the conservation of the native heritage, which is based on the knowledge and study of native breeds. Among the endangered native breeds, there is the Teramana goat, a breed that originated in the province of Teramo, in the Abruzzo region, in Italy. It is important to consider the advantages of native breeds, with phenotypes linked to the climate and geography of the region in which they evolved, and therefore the possibility of acquiring higher-quality productions compared to not native breeds. The overarching goal is to provide valuable data that can contribute to improving reproductive management strategies and conservation efforts for this rare and at-risk breed. This study focuses on the reproductive performance and foetal development of the endangered Teramana goat breed, utilising ultrasonography to monitor pregnancy progression and estimate gestational age. The study aims to measure foetal growth using key biometric parameters such as Biparietal Diameter (BPD), Abdominal Diameter (ABD), Crown-Rump Length (CRL), and Heart Rate (HR) between day 28 and day 125 of gestation. These measurements were found to correlate strongly with gestational age, making them reliable predictors of foetal development. However, Placentome Length (PLL) was not significantly correlated with gestational age, proving less useful as a measurement tool, as demonstrated previously by other authors (Doize et al., 1997; Lee et al., 2005; Abreu et al., 2007; Nwaougu et al., 2010). The study also revealed an important incidence of dystocia among the pregnant goats, particularly in twin pregnancies and those involving male foetuses. Despite relatively large pelvic dimensions, dystocia was prevalent, suggesting that other factors such as foetal positioning or size may contribute more significantly to birthing complications. The findings emphasise the importance of close monitoring during late gestation and parturition, particularly in breeds like the Teramana goat that face high reproductive risks. 3 This research provides essential data on the reproductive management of Teramana goats, highlighting the value of ultrasound as a non-invasive tool for monitoring foetal development and predicting gestational outcomes. The results support the use of this diagnostic method in reproductive management programs in order to develop strategies aimed at increasing the population in those endangered breeds