Effects of the dry and the rainy season on endocrine and physiologic profiles of goats in the Brazilian semi-arid region

Abstract

This study investigated the effect of season on the endocrine and adaptive profiles of a Brazilian Creole goat population in a semi-arid region of Brazil during the dry and the rainy season. We considered physiological, morphological, biochemical, haematological, hormonal and anatomical profiles. The experiment used 80 adult goats (2-to 5-year-old) and lactating (160 ± 14 days of lactation length) goats, with an average daily milk yield of 500.9 ± 13 g. Physiological parameters (rectal temperature, RT; respiratory rate, RR; heart rate, HR; skin temperature, ST) were high (p < .05) in the afternoon in both seasons. There was a significant effect of season (p < .05) on anatomical parameters (hair diameter, HD; hair length, HL; coat thickness, CT). Haematological, biochemical and hormonal parameters were also significantly affected by season (p < .05). We measured the biochemical and hormonal characteristics changes during different seasons; metabolism was reduced during heat stress and accelerated during cold stress. These hormones facilitate the physiological parameters involved in the adaptation process. Our results confirm that the adaptive capacity of the animals cannot be described solely by RT and RR.ARTICLE HISTORY

Wool Production and Characteristics, Physiological and Haematological Parameters and Level of some Metabolic Hormones in Barki Ewes Shorn in Autumn as Alternative of Spring Shearing

“…Al-Eissa et al (2012) observed higher Glb concentration in Nubian goats under cold climatic conditions that led to decreased Alb: Glb ratio. In this line, Ribeiro et al (2018) reported that differences in globulin values are related to physiological and genetic factors of animal adaptation.…”

Effects of coat color pattern and sex on physiological traits and heat tolerance of indigenous goats exposed to solar radiation

“…It is a more specific indicator of PLT activation since it is not elevated during single PLT distention caused by PLT swelling (Vagdatli et al 2010 However, in this study, hematological parameters seem to be most damaged in black coat color goats. According to Ribeiro et al (2018), animals alter hematological parameters to maintain a stable body temperature, i.e., to maintain RT and PR within the limits recommended for this species and they adjust these parameters to survive both food and water shortages as well as high temperatures. This seem to be normal as the black coat color goats were most affected with physiological parameters as well as food and water consumption.…”

The impact of temperature-humidity index on blood morphology and β-hydroxybutyrate in different sheep breeds

“…Evaluation of haematological indices can be an important tool of checking on animal welfare, since blood is an important response indicator to climatic changes (Okourwa 2015). Ribeiro et al (2018) noted that thermal conditions, especially those associated with seasonal periodicity, may directly affect the changes in blood indices. Significant differences between the WBC, NEU, RBC, MCV, MCH, and PLT values between the THI groups were determined.…”

“…Climatic variations directly affect the animals, changing their physiology (Ribeiro et al 2018). The impact of climatic changes has caused much loss in livestock production (Salama et al 2014) -a fact that generates the need for detailed studies to better understand the mechanisms of animal adaptation to a changing climate.…”

“…The blood system is sensitive to temperature changes and is an important indicator of physiological responses to stressors (Bezerra et al 2008;Al-Eissa et al 2012). The results show the variations in haematocrit values, mean erythrocyte count and haemoglobin (Ribeiro et al 2018). Erythrocytes vary in diameter and thickness depending on the breed and nutritional status of the animal.…”