Effects of the season on physiological and endocrine traits and on HSP70 in Saanen goats under Mediterranean climate conditions

Abstract

This study was conducted to determine the impact of heat stress on some physiological and endocrine traits in Saanen goats raised under Mediterranean climate conditions. The effects of thermal stress on heart rate (HR), respiration rate (RR) and rectal temperature (RT) on plasma total trii-odothyronine (T3), thyroxine (T4), Cortisol (C), and HSP70 concentrations were evaluated on twenty two Saanen goats of different ages in the second week of April 2013, July 2013, October 2013 and January 2014. Climatic data such as temperature (°C) and relative humidity (%) were recorded from Spring 2013 to Winter 2014. Live body and BCS values were also recorded during this period. The physiological parameters above were measured twice on each experiment day (morning and afternoon) in all seasons. Blood samples were collected in each afternoon of the experiment day to analyze T3, T4 C, and HSP70. All data were analyzed. According to the values of rectal temperature (RT), it was estimated that the goats were under extreme heat stress only in the summer season. The heart rate (HR) values in the winter season for morning and noon periods were found statistically significant (p < 0.05). The average respiratory rate (RR) in the spring season was found significantly lower. On the other hand, the RR for the noon period in the summer was higher than in the fall and winter seasons (p < 0.05). There was a significant difference (p < 0.05) between summer and fall seasons for C values. The highest value (96.62 ng/ml) was obtained in spring, whereas the lowest (60.58 ng/ml) in the fall. T3 levels in the fall and winter were found to be statistically significant (p < 0.05). They were the highest in the winter and spring, and the lowest in fall. T4 and T4/T3 levels in the winter were found to be statistically higher than in other seasons (p < 0.05). The lowest value for T4 was found in the fall and for T4/T3 in summer. Mean HSP70 value in spring was found to be statistically low (p < 0.05). The changes in THI values in different seasons, particularly between mornings and afternoons, indicated that thermal stress was evident, and that the animals became resistant to it eventually. The fluctuations of the C, T3, T4 and HSP70 values were indicators of the animals’ reaction to thermal stress. The THI values in spring, which were between 16 and 18 THI, may be considered within the ideal comfort zone for goats. It was observed that Saanen goats were able to adapt to seasonal weather changes in the environmental conditions of the region....

Effects of Feed Supplementation on Nesfatin-1, Insulin, Glucagon, Leptin, T3, Cortisol, and BCS in Milking Ewes Grazing on Semi-Natural Pastures

“…Regarding the COR peak observed in SUP ewes at the last sampling, different papers report similar effects by heat stress in small ruminants [ 46 , 47 ]. The serum COR levels were the highest during summer [ 43 , 44 , 45 , 46 , 47 , 48 , 49 ] and positively correlated with ambient temperature, showing reverse trends and negative correlations with TH [ 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ]. Moreover, during thermal stress, feed-restricted ewes [ 51 ] and rams [ 25 ] showed less increase in cortisol blood concentrations: therefore, if the nutritional deficit is added to thermal stress, the animals can adjust their response, avoiding the potential adverse effects of extreme cortisol action, as it could be the case of the UNS group of the present study.…”

“…The farm where our ewes were kept suffered a lot of damage, as well as the houses of the farmers, so it was not possible to carry on the intended further controls, and the overall situation after the earthquake could have direct and indirect effects influencing the results. Despite this accident, fortunately, we had the possibility to have some indication from research performed on other ewes of the same flock, which showed that the feed supplementation had a positive effect on resistin production in the sheep uterine glands [ 52 ] and in the apelinergic system expression in both mammary glands and female reproductive apparatus [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 ].…”

Changes in the goat’s milk composition due to heat stress at the farm of the Ukrainian steppe zone

“…Рівень трийодтироксину найвищий узимку та навесні, а найнижчий восени, а тироксину -взимку був статистично вищим, ніж в інші сезони (Р < 0,05), особливо восени. Білок теплового шоку 70 (HSP70) у плазмі виявився навесні статистично низьким (Р < 0,05), його зміни відображали коливання значень ТВІ в різні сезони, особливо за термічного стресу влітку (Yilmaz et al, 2018).…”

“…Зааненські кози можуть адаптуватися до сезонних змін погоди та екологічних умов регіону. Автори з Туреччини використали розрахунки за формулою ТВІ = T -(0,31 -0,31 • RH) • (T -14,4), яку запропоновано для овець, означають відсутність теплового стресу при значенні ТВІ < 22,3, стрес середньої сили в інтервалі 22,3 ≤ ТВІ < 23,3, загрозливий -23,3 ≤ ТВІ < 25,6, а надзвичайний при перевищенні 25,6 (Yilmaz et al, 2018).…”