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We aimed to analyze the seasonal acclimatization process of Nelore and Canchim cattle raised on two production systems (non-shaded, NS, and integrated crop-livestock-forest, ICLF), based on the dynamics of the morphological and functional attributes of the hair coat and skin during winter and summer. The study was conducted in Brazil, in a low-altitude tropical climate region. A completely randomized 2 × 2 factorial design was adopted as follows: two production systems (NS and ICLF), two breeds (Nelore and Canchim) in a longitudinal structure, with measurements repeated over time through two stations (winter and summer). The experimental animals consisted of 32 Nelore (Bos indicus) and 32 Canchim (5/8 Bos taurus × 3/8 Bos indicus) bulls. The animals were equally distributed between two intensive rotational grazing systems. In both breeds, the hair coat was significantly thicker in winter but longer in summer, which increased epidermal protection. The Nelore bulls had shorter, wider, and thicker hairs, which are attributes that promote heat loss via conduction. The Canchim bulls showed significantly lower hair density and higher epithelium distance to sweat glands, which resulted in higher core temperature and respiratory rate. In turn, Nelore bulls had higher serum concentrations of triiodothyronine and lower serum concentrations of cortisol. However, Canchim bulls more frequently and intensely activated their thermoregulatory system and markedly adjusted their hair coat and hair features to reduce heat gain, especially in summer. Therefore, the anatomical plasticity and functional integumentary characteristics of Nelore and Canchim bulls reflect their acclimatization to tropical conditions.

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The objective was to evaluate the differences between hair lambs, born from single or twin births, regarding the latency periods for standing up and suckling, the vitality, glycemic, cortisol, and triiodothyronine concentrations, as well as the phenotypic characteristics related to the maintenance of homeothermy in the immediate postpartum. Single (n = 10) or twin (n = 12) Morada Nova lambs were evaluated after birth, during the first successful suckling (M0 = Timepoint 0), and at regular intervals of 20 min (M20, M40, M60). Lambs from single births had higher birth weight (3.09 vs 2.58 kg; P ≤ 0.05) and higher serum triiodothyronine concentration (267 vs 209 ng/dL; P ≤ 0.05) compared to twin lambs. There was a positive correlation between weight and blood glucose (0.57; P ≤ 0.05) for both single and twin lambs. The type of birth did not affect vitality, which was negatively associated with cortisol concentration (-0.53; P ≤ 0.05). Twin lambs had higher internal and ocular temperatures (39.29 vs 38.67 °C and 38.84 vs 38.13 °C; P ≤ 0.05, respectively). Body surface temperatures increased over time in both groups (P ≤ 0.05). An increase in the temperature of the hips region (ysingle = 27.88 + 0.019*time; R2 = 0.96; P = 0.019 and ytwin = 28.74 + 0.019*time; R2 = 0.94; P = 0.029) was observed for both single and twin lambs, which coincides with the region of brown adipose tissue deposition. The lowest absolute thermal variabilities between twin and single lambs in M0 and M60 were recorded in the midloin and integral dorsal area. The parturition type did not influence the latencies to stand up (P = 0.908) and for the first suckling (P = 0.888), and the vitality score (P = 0.353). Thus, single and twin lambs do not differ in neonatal behavior, but they presented specific metabolic strategies to regulate body temperature over time. Midloin and integral dorsal areas are anatomical regions suggested for use in serial thermographic monitoring. Infrared thermography may be an important complementary resource in neonatal care.

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The aim was to compare the early luteal development in ewes superovulated with different doses of pFSH. Twenty-nine Santa Inês ewes received a progesterone device (CIDR®) for 8 days. Gonadotrophic treatment started on Day 6: G200 (control, n = 9, 200 mg); G133 (n = 10, 133 mg); and G100 (n = 10, 100 mg of pFSH). On Day 6, all females received eCG (300 IU). B-mode and spectral Doppler ultrasonography were performed daily during the early luteal phase (Days 11-15) to monitor the development of corpora lutea (CLs; dimensions) and ovarian arteries indices. CLs were also classified as normal or prematurely regressed (PRCL) on Day 15 by videolaparoscopy. Ewes from G100 and G133 showed gradual increase in luteal diameter during the early luteal phase (p < 0.001), whereas G200 animals presented increase from Day 11 to Day 13, and then decrease on Days 14 and 15 (p < 0.001). The G200 females showed greater percentage of PRCL (45.20%) than those of the other groups (p < 0.001). The normal CLs number was greater in G100 than in G133 (p = 0.04), while the PRCL number was greater in G200 than in the other groups (p = 0.03). Resistive index (RI) was greater in G200 than in G100 (p = 0.02). RI was lower in Day 12 than Day 15 (p = 0.02). Pulsatility index (PI) was greater on Days 14 and 15 (p < 0.01). In conclusion, the lowest dose of pFSH (100 mg) can be considered sufficient for an efficient superovulatory response in sheep, producing better CLs development dynamic in early luteal phase and ovarian blood perfusion and smaller number of PRCL than the traditional (200 mg) pFSH dose.

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Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P 0.05) values for most of motility parameters over time of incubation. The control group led to more (P 0.05) capacitated

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Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P 0.05) values for most of motility parameters over time of incubation. The control group led to more (P 0.05) capacitated

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Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P 0.05) values for most of motility parameters over time of incubation. The control group led to more (P 0.05) capacitated

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Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P 0.05) values for most of motility parameters over time of incubation. The control group led to more (P 0.05) capacitated

RESUMEN

Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P 0.05) values for most of motility parameters over time of incubation. The control group led to more (P 0.05) capacitated

RESUMEN

Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P 0.05) values for most of motility parameters over time of incubation. The control group led to more (P 0.05) capacitated

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This study evaluated the presence of vaginitis and the bacterial load associated with different intravaginal implants in ewes. Twenty-four Dorper and crossbred ewes were allocated into three groups and received intravaginal implant containing 0.3g progesterone (CIDR(r)), 60mg MAP or sponges without progesterone (CONTROL) for six days. Then, CIDR and MAP treated-ewes received 12.5mg dinoprost and 300IU eCG. Vaginal mucus samples were collected at four times: before device insertion, at the day of its removal, 24 and 48 hours after. The samples were cultured and the colonies were counted (CFU/mL) and identified. The results obtained from the counting of CFU mL-1 were submitted to Kruskal-Wallis H test, with P 0.05 being considered significant. Before device insertion, 68.2% of the samples yielded Staphylococcus spp. and 60.0% of them were Staphylococcus aureus. After implant removal, 100% of ewes had clinical signs of vaginitis. However, the level of local infection in the CONTROL-ewes was lower (P>0.05) in comparison with MAP and CIDR-treated ewes. During the occurrence of vaginitis, the predominant isolates belonged to the coliform group, mainly Escherichia coli (72.7%). Such infection was not determined by the members of the vaginal microbiota that were present before implant insertion and normal microbiota was restored between 24 to 48 hours after insert removal.(AU)

Este estudo avaliou a presença de vaginite e contagem bacteriana associada ao uso de diferentes dipositivos intravaginais em ovelhas. Vinte e quatro fêmeas Dorper e mestiças foram alocadas em três grupos e receberam implante intravaginal contendo 0,3g de progesterona (CIDR(r)), 60mg de acetato de medroxiprogesterona (MAP) ou esponjas sem progesterona (CONTROLE) por seis dias. Posteriormente, as ovelhas tratadas com CIDR e MAP receberam 12,5mg de dinoprost e 300 UI de eCG. Amostras do muco vaginal foram coletadas em quatro momentos: antes da inserção do dispositivo, no dia de sua retirada, 24 e 48 horas após. As amostras foram cultivadas e as colônias foram contadas (UFC mL-1) e identificadas. Os resultados obtidos da contagem das UFC mL-1 foram submetidos ao teste do qui-quadrado, com P 0,05 sendo considerado significativo. Antes da inserção do dispositivo, 68,2% das amostras continham Staphylococcus spp., sendo 60,0% delas Staphylococcus aureus. Após a remoção do implante, 100% das ovelhas apresentaram sinais clínicos de vaginite. Entretanto, o grau de infecção local nas ovelhas do grupo CONTROLE foi menor (P>0.05), em comparação com as ovelhas recebendo CIDR e MAP. Durante a ocorrência da vaginite, os isolados predominantes pertenciam ao grupo dos coliformes, principalmente Escherichia coli (72,7%). Tal infecção não foi determinada pelos membros da microbiota vaginal, que estavam presentes antes da inserção dos dispositivos, e a microbiota normal foi reestabelecida entre 24 e 48 horas após sua remoção.(AU)

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Toxoplasma gondii is one of the most widely studied parasites due to its medical and veterinary importance. The parasitic infection of sheep occurs worldwide, with studies showing prevalences ranging from 1.8% in North Tunisian to 95.7% in Turkey. In this ruminant species, infection with T. gondii causes fetal death, mummification, stillbirth, the birth of debilitated animals and frequent abortion. The latter has been reported as the primary cause of economic losses in the sheep industry because of the high rates of infection. Concerns over toxoplasmosis infections in sheep, as well as the economic losses they can cause, induced this literature review. A review of the topic will provide the reader with some basic information concerning the importance of this parasite in the sheep industry in Brazil and worldwide, which might assist in controlling the disease and promptly identifying the problem in a flock, thus avoiding losses from potential abortions caused by this important parasite.