Climatic seasons and time of the day influence thermoregulation and testicular hemodynamics in Santa Inês rams raised under humid tropical conditions.

This study evaluated the possible association between the diurnal variations of climatic factors during the rainy (RS) or less rainy (LS) seasons on the testicular hemodynamics and thermoregulatory responses of hair sheep rams raised in a humid tropical climate. Santa Inês rams (n = 6) underwent evaluation of general and testicular physiological parameters (heart and respiratory rates, internal and scrotal temperatures, internal-scrotal temperature gradient, scrotal distention, and color Doppler ultrasound evaluation of the spermatic cords and spectral analyses of testicular arteries) over six consecutive weeks per season at three separate times daily (morning = 8:00 a.m., noon = 12:00 p.m., and afternoon = 5:00 p.m.) during the RS and LS. Climatic air temperature and relative humidity data were recorded, and the temperature and humidity index (THI) was calculated. Higher thermal challenge was observed in LS relative to RS (air temperature = 28.0 vs. 30.9 °C; relative humidity = 84.1 vs. 69.9%; THI = 80.0 vs. 82.5; P < 0.05). In both seasons, respiratory rate and internal temperature were normal, demonstrating the animals' adaptability. In RS, however, a higher scrotal temperature was recorded in relation to LS (35.0 vs. 34.7 °C; P < 0.05), with a gradual increase from morning to afternoon. Lower resistivity (0.40 vs. 0.64; P < 0.05) and pulsatility (0.55 vs. 1.14; P < 0.05) indices, and a higher rate of high-velocity blood flow of testicular arteries (71.1 vs. 60.6%; P < 0.05) were observed in RS compared to LS. The lowest correlations between testicular hemodynamic, physiological variables, and environmental parameters (P < 0.05) were observed in the morning. In conclusion, testicular thermoregulation and testicular hemodynamics were influenced by the climatic seasons and time of the day, being more efficient in the LS season and with less interference from environmental factors in the morning.

Behavioral aspects of Santa Inês sheep kept in pasture in a tropical rainforest climate / Aspectos comportamentais de ovinos da raça Santa Inês mantidos em pasto em clima tropical úmido

ABSTRACT: This study aimed to evaluate behavioral aspects of Santa Inês sheep in pasture in humid tropical climate. In order to do so, nine Santa Inês sheep were kept on pasture, exposed to the climate directly, without shade, for 24 days, with 12 alternate days in each period (dry and raining) in 2015. The behavioral parameters evaluated were: food consumption, standing idleness, lying idle and rumination. Observations occurred from 08:00 A.M. to 05:55 P.M. The experimental was a completely randomized design (CRD) with two treatments (rainy season and dry period), nine replications, one animal per experimental unit. To understand the correlations of the behavioral parameters with the climatic variables, Pearson's correlation was performed. Approximate average values between the rainy and dry periods for the behavioral variables were observed, but there was a greater intake in the volume of water in the dry period (9.59L/sheep). Also, there were significant differences in the behavior of the animals throughout the day. In the hottest time of the day, at 02:00 P.M., there was standing idle of 25.83min., lying idle of 1.21min., and spent less time-consuming food (27.08min.) in relation to other schedules. We concluded that the sheep had similar behavioral parameters in the rainy and dry periods, but when we observe the times of the days, the behaviors are different. The main activity recorded was grazing, and the variables, temperature and relative humidity of the air influence differently between the seasons, being more marked in the dry period.

RESUMO: Este estudo objetivou avaliar aspectos comportamentais de ovinos Santa Inês criados em pasto em clima tropical úmido. Para tanto, foram utilizados nove carneiros Santa Inês, mantidos a pasto, expostos diretamente ao clima, sem sombra, durante 24 dias, sendo 12 dias alternados em cada período (seco e chuvoso) em 2015. Os parâmetros comportamentais avaliados foram consumo de alimento, ócio em pé, ócio deitado e ruminação. As observações ocorreram das 08:00h às 17h:55min. O delineamento experimental foi o inteiramente casualizado (DIC) com dois tratamentos (período chuvoso e período seco), nove repetições, um animal por unidade experimental. Para entender as correlações dos parâmetros comportamentais com as variáveis climáticas foi realizada a correlação de Pearson. Foram observados valores médios gerais aproximados entre os períodos chuvoso e seco para as variáveis comportamentais, porém, houve maior ingestão no volume de água no período seco (9,59L/ovino). Também, ocorreu diferença no comportamento dos animais ao longo do dia. No horário mais quente do dia, das 14h às 15h, registrou-se ócio em pé de 25,83min. e ócio deitado de 1,21min., e os animais passaram menor tempo consumindo alimento (27,08min.) em relação aos demais horários. Podemos concluir que os ovinos apresentaram parâmetros comportamentais semelhantes nos períodos chuvoso e seco, porém, quando observamos os horários dos dias, os comportamentos são diferentes. A principal atividade registrada foi o pastejo. As variáveis temperatura e a umidade relativa do ar influenciam de forma diferente o comportamento dos ovinos entre as estações do ano, sendo mais marcantes no período seco.

Reproductive and productive performances of Santa Inês ewes submitted to breeding in different periods of the Amazonian humid tropical climate.

The objective of this study was to evaluate the reproductive and productive performance of Santa Inês ewes bred at different times of the year in humid tropical climate. One hundred and forty-eight Santa Inês ewes were grouped according to the time of the year of their breeding season (i.e., mating period) (dry/wet, wet, wet/dry, and dry season). The service type was natural mating and the ewes and rams were kept together every night for 45 days. Reproductive efficiency was assessed by service, pregnancy, lambing, prolificacy, twinning, pregnancy loss, weaning, and lamb mortality rates. Ewes were weighed at the beginning and at the end of the breeding season and before and after parturition, and sequential weighing of the lambs was performed (at birth, 15, 30, 60, and 90 days). Reproductive efficiency index (number of lambs weaned/total of served ewes) and productive efficiency (kg of weaned lamb/kg of served or lambed ewes) were calculated. All ewes expressed estrus early in the breeding season; however, a higher percentage (53.5 and 7.1 % at 30 and 45 days, respectively) of ewes returned to estrus during the wet/dry period. The lower rates (13.9 %) of return to estrus at 30 days were during the wet season (P < 0.05). There were no (P > 0.05) effects of breeding seasons on the remaining reproductive rates. Ewes that lambed during the wet/dry transition period weighted less, before (40.5 ± 2.5 kg) and after (38.6 ± 1.6 kg) parturition, than those of other groups (P < 0.05). Lamb weight at birth did not vary between groups, however, weight at weaning was higher (15.6 ± 2.1 kg) in lambs born during the wet season (P < 0.05). The reproductive efficiency index was lower (0.66) when the breeding season took place during the dry/wet period (P < 0.05). Productive rates were significantly higher (0.29 and 0.33 for kg of weaned lamb/kg of served and lambed ewes, respectively; P < 0.05) in ewes served in the dry season. The reproductive performance of Santa Inês ewes was not significantly influenced by the period of the year in which the breeding seasons took place, allowing for four breeding seasons a year in the Amazon region. Variations between periods in return to estrus rates, weight of ewes close to parturition and lamb weight at weaning indicate that climate changes can also affect reproductive rates.

Does supplemental LH changes rate and time to ovulation and embryo yield in Santa Ines ewes treated for superovulation with FSH plus eCG? / Suplementação com LH modifica a taxa e momento da ovulação e a produção de embriões em ovelhas Santa Inês superovuladas com FSH e eCG?

The objective was to evaluate if supplemental LH given at the end of FSH treatment would synchronize the time of ovulation and increase the ovulation rate and embryo yield in Santa Ines ewes. Twenty superovulatory (SOV) programs were accomplished in cross-over design (60d interval). On D0, a CIDR device was inserted, and the device was replaced with a new one 7 days later, when 37.5µg of d-cloprostenol was administered. On D12, we started the SOV treatment, administering 256mg of pFSH 8 times, 12h apart. On D14, the CIDR was removed, and 200IU of eCG and 37.5µg of d-cloprostenol were administered. On D15, the ewes were allocated into one of two groups, a Control group (n=10) that received no supplemental LH and a LH group (n=10) treated with 7.5mg of LH 24h after CIDR removal. Artificial inseminations (AI) were performed 42 and 48h after CIDR removal. The ovarian structures were evaluated by laparoscopy immediately before each AI and 5 days later (D21) when the embryos were collected. The LH ewes ovulated more frequently (P=0.05) before 42h than between 42 and 48h. Treatment with LH tended to increase the frequency of CL and to decrease the anovulatory follicles (P=0.08). The supplemental LH increased the frequency of ewes with a high SOV response (≥11 CL; P=0.05). In conclusion, supplemental LH increased the frequency of ewes with high SOV response and ovulating prior to 42h, however, there was no synchrony between ovulations. The supplemental LH also decreased the frequency of anovulatory follicles, although the ovulation rate and embryo yield were unaffected.

O objetivo deste trabalho foi avaliar se a suplementação com LH ao final do tratamento gonadotrófico sincroniza o tempo das ovulações e incrementa a taxa de ovulação e produção de embriões em ovelhas Santa Inês. Vinte programas de superovulação (SOV) foram realizados em delineamento cross-over (intervalo de 60 dias). No D0, um CIDR foi inserido, sendo trocado por um novo sete dias após, quando 37,5µg de d-cloprostenol foram administradas. No D12, iniciou-se o tratamento com 256mg de pFSH em 8 administrações (12/12h). No D14, o CIDR foi retirado, 200UI de eCG e 37,5µg de d-cloprostenol foram administradas. No D15, as ovelhas foram alocadas em um dos dois grupos: Controle (n=10), sem suplementação com LH, e LH (n=10), tratado com 7,5mg de LH, 24h após a remoção do CIDR. Inseminações artificiais (IA) foram realizadas 42 e 48h após a remoção do CIDR. As estruturas ovarianas foram avaliadas por laparoscopia imediatamente antes de cada IA e 5 dias após, quando os embriões foram colhidos. As ovelhas que receberam o LH tiveram maior frequência de ovulações antes de 42h (P=0,05). O tratamento com LH tendeu em incrementar a frequência de CL e diminuir a de folículos anovulatórios (P=0,08). A suplementação com LH incrementou (P=0,05) a frequência de ovelhas com alta resposta superovulatória (≥11 CL; P=0,05). Em conclusão, a suplementação com LH incrementou a frequência de ovelhas com alta resposta e ovulações antes de 42h depois da remoção do CIDR, entretanto, não houve sincronia entre as ovulações. A suplementação diminuiu a frequência de folículos anovulatórios, embora a taxa de ovulação e a produção de embriões permaneceram inalteradas.

Caracterização da adenosina desaminase (ADA) e suas isoenzimas em tecidos de caprino: um modelo para o estudo da artrite encefalite caprina (CAE) / Characterization of the adenosine deaminase (ADA) and their isoenzymes from goat tissues: a model for the study of caprine arthritis encephalitis (CAE)

A adenosina desaminase (ADA), uma aminohidrolase (E.C.3.5.4.4) de fundamental importância na via metabólica das purinas, vem sendo alvo de estudos por seu envolvimento com o sistema imunológico e utilização como ferramenta diagnóstica em várias desordens patológicas. Entretanto, pouco se sabe sobre sua expressão em caprinos. A atividade sérica da ADA caprina apresentou um pH ótimo de 7,2, Km aparente de 49,19+-5,28 μM para a adenosina (Ado) e de 41,28+-4,58 μM para 2'-deoxiadenosina (dAdo). A enzima é estável pelo menos até trinta dias a -20°C com termoestabilidade até um máximo de 53°C por 1 hora, sendo inativada aos 60°C em dez minutos. A atividade da ADA (nmoles/mg prot/min) foi detectada em fígado (3,35+-0,51), coração (3,71+-0,49), duodeno (83,54+-9,72), baço (51,15+-4,82) e pulmão (7,23+-0,92), tendo como substrato a Ado. Utilizando a dAdo foram obtidas as atividades de 3,23+-0,82; 2,73+-0,76; 79,22+-6,62; 49,72+-5,78 e 7,38+-1,13, respectivamente. A filtração molecular em gel Sephadex G200 mostrou três isoformas em duodeno (picos 1,2 e 3), tendo o pico 2 atividade predominante. O pico 3 surgiu quando amostras (homogenato ou frações do pico 1) foram congeladas. O fígado revelou dois picos (1 e 3), sendo o pico 1 o de maior atividade. O pico 3 mostrava aumento da atividade quando o homogenato era congelado. Somente uma isoforma foi detectada no baço, correspondendo ao pico 2. Utilizando os substratos Ado e dAdo o pico 1 apresentou um Km de 6,26+-1,41 μM e 35,82+-3,84 μM, respectivamente e o pico 3 um Km de 5,42+-0,68 μM e 32,89+-3,64 μM, com um pH ótimo de 6,8...