Multivariate characterization of the adaptive profile in Brazilian and Italian goat population

Abstract

a b s t r a c tThe aim of this study was to characterize the adaptive profile and identify variables with great discriminatory power of the Brazilian Azul goat population and Italian Garfagnina population, through the use of principal component and canonical discriminant analysis. A total of 110 Garfagnina milking females (60 in winter and 50 in summer) and 80 Brazilian Azul (40 in winter and 40 in summer) were considered. Air temperature ( • C), black globe temperature (BGT) and relative humidity (%) were measured with the aid of an automatic weather station. Some physiological parameters (rectal temperature -RT, respiratory rate -RR, skin temperature -ST and heart rate -HR), some anatomical parameters (hair diameter -HD and hair length -HL), some hematological parameters (erythrocyte -RBCs, packed cell volume -PCV and mean corpuscular volume -MCV), some blood biochemical parameters (glucose -GLI, cholesterol -COL, triglycerides -TRI, creatinine -CRE, urea -URE, total protein -PRT, albumin -ALB, globulin -GLO, albumin and globulin ratio -A/G, gamma -glutamyl transferase -GGT and aspartate aminotransferase -AST) and some stressed hormones (thyroxine -T4, triiodothyronine -T3 and cortisol -COR) were measured. The variables with greater discriminant power were T3, ST, COR, T4, GGT, HD, GLO, HL and PCV to Garfagnina population and PRT, MCV, PCV, ALB, T4, ST, HL, RBCs, TRI and GGT in the Azul Brazilian population. Classification of the animals was more accurate when considering morphological, physiological, hematological, biochemical and hormonal variables jointly.

Influence of seasonal changes on physiological variables, haematology and serum thyroid hormones profile in male Red Sokoto and Sahel goats

“…However, during the CDS, significantly higher PCV, RBC and Hb were observed in Red Sokoto than Sahel goats. Similarly, breed difference in haematological parameters of goats during the winter season has been reported by Ribeiro et al (2015). The low erythrocyte parameters in Sahel compared to Red Sokoto goats is probably due to the lower body temperature in the Sahel goats.…”

“…The MCV as an indirect measure of the average size of individual erythrocytes was lower in both breeds during the HDS in comparison to the CDS and RAS. Similarly, exposure to natural heat stress has been reported to cause an increase in MCV of Brazilian Azul goats (Ribeiro et al 2015) and Piemontese cattle (Mazzullo et al 2014). The decrease in MCV during the heat stress of the HDS may be due to an increase in body temperature, which causes an increase in the number of erythrocyte membrane vesicles formed and shed from the erythrocytes with a resultant decrease in the size of the parent erythrocytes (Foller et al 2010;Moore et al 2013).…”

“…The low erythrocyte parameters in Sahel compared to Red Sokoto goats is probably due to the lower body temperature in the Sahel goats. As animal with low body temperature do not sweat and, thus maintain blood volume (Indu et al, 2014;Ribeiro et al, 2015). In addition, decrease in RBC has been reported in animals exposed to extreme cold and has been associated with reduction in the half-life of erythrocytes (Ruiz et al 2004).…”

“…On the other hand, little is known about the adaptation of animals to the rapidly changing environmental conditions in developing countries of the arid and semiarid regions, where the stressors are different and the intensity of expected changes from one season to the other is greater (Thornton et al 2007). Physiological changes in blood cellular components, free radical biology, as well as endocrine, respiratory and cardiovascular systems have been used as important parameters to evaluate the adaptation of animals to a given geographical location Ribeiro et al 2015). This may help in the selection of animals that are capable of producing satisfactorily in harsh environments and outside the zone of thermal comfort (Ribeiro et al 2015).…”

“…Physiological changes in blood cellular components, free radical biology, as well as endocrine, respiratory and cardiovascular systems have been used as important parameters to evaluate the adaptation of animals to a given geographical location Ribeiro et al 2015). This may help in the selection of animals that are capable of producing satisfactorily in harsh environments and outside the zone of thermal comfort (Ribeiro et al 2015). Therefore, this study was carried out to evaluate the adaptation of Red Sokoto and Sahel bucks to the seasons of the Northern Guinea Savannah zone of Nigeria by evaluating the changes in physiological variables, haematology, erythrocyte osmotic fragility (EOF) as a biomarker of oxidative stress and serum thyroid hormones concentration.…”