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Background: In tropical countries like Brazil, air temperature and relative humidity have a significant effect on animal physiology; there is a great impact of solar radiation on physiological parameters, especially on body temperature. This study evaluated the occurrence of heat stress in Brown Swiss cows in a tropical semi-arid climate, and checked for the correlation between internal body temperatures [rectal temperature (RT) and vaginal temperature (VT)] with surface temperature (ST) to determine if these variables are associated.Materials, Methods & Results: Twenty-eight Brown Swiss cows at three stages of the lactation cycle were used in this study: 10 nonpregant lactating (NPL) cows, 8 dry pregnant (DP) cows, and 10 pregnant lactating (PL) cows. These animals were between the second and third calving, weighed between 346 and 720 kg, and had ages between 2 and 13 years. During the experimental period, air temperature and relative humidity (RH) at the experimental site were measured using a digital thermohygrometer. The temperature and humidity index (THI) was calculated according to methodology described by Thom (1958), and was used as an environmental comfort parameter. For the evaluation of RT and VT, two digital clinical thermometers, one inserted in the vagina and the other in the rectum, were used simultaneously to minimize stress. Surface temperature (ST) was assessed using a digital infrared laser thermometer at a distance of 50 cm from the animal. Surface temperature was measured in the forehead (FST), thorax (TST), flank (FLST), and legs (LST). During the study period, the ambient temperature (AT) was significantly higher outside (in the sun) than inside of the facilities (in the shade) (P < 0.05). RH was inversely proportional to AT, and was significantly higher inside than outside the facilities (P < 0.05). Like AT, THI was significantly higher outside (in the sun) than inside the facilities (in the shade), with significant differences between these locations (P < 0.05). The amplitudes of the differences between the locations were as follows: 3.8°C for AT, 6.2% for RH, and 2.6 for THI. Mean values of rectal and vaginal temperatures were not significantly different from each other independent of lactation cycle stage, and were almost always significantly higher than the measured surface temperatures (P < 0.05). The maximum values obtained for each lactation cycle stage in this study were higher when compared to the mean values, showing that they are more representative of the occurrence of heat stress. Correlations between internal temperatures (RT and VT) and surface temperatures (TSF, TST, TSFL, and TSP) were weak and non-significant. ST values exhibited mostly weak, non-significant correlations, with the exception of FST with FLST and LST, which had moderate, significant correlations, as shown by the following coefficient factors: FST x FLST, 0.34; LST x FST, 0.415; and LST x FLST, 0.37.Discussion: A temperature of 34°C with RH ranging from 46% to 80% (i.e., a THI between 83 and 89) has been reported to have a significant thermal impact on dairy Brown Swiss cows; the THI values found in the present experiment were close to those. Body temperatures exhibited significant variations depending on the lactation cycle stage of the cows. Lactation concomitant with pregnancy significantly increases internal temperatures (RT and VT) in DP and NPL cows. This finding may be explained by the fact that pregnancy concomitant with lactation accelerates the metabolism, which results in higher food intake and increased production of body heat with consequent increase in internal body temperature. The maximum values of internal body temperatures (RT and TV) at all stages of the lactation cycle were higher than their corresponding average values, which indicates that some cows exhibited, at given moments, hyperthermia.

Testicular degeneration is a multifactorial process increasing the concentration of prostaglandins in seminal plasma. Both increase and decrease of these hormones tend to promote loss of seminal quality. Flunixin meglumine is a potent anti-inflammatory drug capable of modulating the production of prostaglandins and is widely used in female reproduction. However, it is rarely used in males with the same objective. Therefore, this study aimed to evaluate the effects of this drug on seminal quality of male lambs and goats with spermatic characteristics unfavorable for reproduction. To this end, a total of 15 breeding animals were evaluated, of which six goats and four sheep with poor seminal quality were selected according to the criteria established by the Brazilian College of Animal Reproduction (CBRA). Three semen samples were collected from each animal. Then, the flunixin meglumine treatment was initiated and ejaculates were collected at two different periods after the drug was administered (from day 21 until day 35 and from day 49 to day 63). Macroscopic and microscopic parameters were assessed in semen samples and scrotal circumference and percentages of sperm pathologies were measured and compared between the three periods. Data with normal distribution were analyzed using ANOVA at 5% probability, and comparisons between periods within the same species were performed using the Tukey test. An improvement was observed in the analyses of mass motility, percentage motility, and sperm vigor. Scrotal circumference had no variation. Concerning sperm pathologies, an increase in the number of normal spermatozoids was observed due to a significant reduction in minor and major defects, and the latter remained low even after the treatment was finished. Therefore, flunixin meglumine presented beneficial effects on seminal parameters of male goats and lamb with unfavorable spermatic characteristics. These findings indicate this drug may be used in the treating of males with testicular injuries or of breeders with reduced seminal quality due to advanced age. Key words: Andrology. Animal Reproduction. Prostaglandins. Seminal Quality. ResumoA degeneração testicular é um processo multifatorial que leva ao aumento das prostaglandinas no plasma do ejaculado, sendo que tanto seu acréscimo quanto a redução baixam a qualidade seminal. A Flunixina Meglumine é um potente anti-inflamatório, capaz de modular a produção de prostaglandinas, amplamente difundido na reprodução de fêmeas, mas pouco utilizado em machos para esse fim. Por isso, esse trabalho buscou avaliar o efeito deste fármaco sobre a qualidade seminal de machos ovinos e caprinos que apresentem quadro espermático desfavorável à reprodução. Para tanto, um total de 15 reprodutores pertencentes à Universidade Federal do Ceará foram avaliados, dos quais foram selecionados seis bodes e quatro carneiros com sêmen de baixa qualidade, segundo os critérios do Colégio Brasileiro de Reprodução Animal (CBRA). Foram realizadas três colheitas prévias de cada animal, aplicado o ...