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Semi-arid conditions can adversely affect livestock productivity and change certain physiological parameters. The relationship between hair coat and thyroxine levels in Morada Nova ewes was evaluated through environmental factors, such as air temperature, relative air humidity, radiant and Black Globe Humidity Index to gain a better understanding of thermoregulation mechanisms in these animals. Measurements were taken from July to January in 383 Morada Nova ewes. The variables studied included rectal temperature (RT), respiratory rate (RR), coat thickness (CT), hair length (HL), hair diameter (HD), hair density (D) and thyroid hormones. The data underwent multivariate statistical analyses and a significant inverse relationship was found between coat traits and Thyroxine (T4). The animals that exhibited greater HL, coat density and CT showed lower T4 concentrations. Coat traits showed a strong interaction with physiological mechanisms and can be considered relevant in maintaining homeostasis. Hair traits play an important role in this process, since T4 reduction was stronger in animals that showed difficulties in eliminating heat, which were the ones that had greater HL, hair density and HD. By contrast, animals with a hair coat more favourable to heat losses had higher levels of thyroid hormones.

This study aimed to verify the effects of cryoprotectant and Open Pulled Straw (OPS) vitrification on ultrastructural changes in bovine oocytes. In experiment 1, the cryoprotectant exposure was analyzed by distributing immature and matured cumulus-oocyte complexes (COCs) in groups: control immature, immature and exposed to one vitrification solution (IVS1), immatured and exposed to two vitrification solutions (IVS1-2), matured and exposed to one vitrification solution (MVS1), matured and exposed to two vitrification solutions (MVS1-2), control matured, IVS1 post in vitro maturation (IVS1 post IVM) and IVS1-2 post in vitro maturation (IVS1-2 post IVM). In experiment 2, immature and matured COCs were distributed in: control and vitrified by OPS using VS1-2. Sample COCs from both experiments were evaluated for mitochondrial distribution, nuclear lamins (immature COCs) and meiotic spindle (matured COCs). In both experiments, COCs were in vitro matured and fertilized. In experiment I, nuclear lamins in immature COCs exhibited higher proportion of structures with irregular shape when treated with VS1 and VS1-2. Immature and matured COCs treated with VS1-2, and matured COCs treated with VS1 had lower (P < 0.05) blastocyst development (29%, 20% and 8%, respectively) than control and immature COCs treated with VS1 (51% and 41%, respectively). In experiment 2, immature oocytes exhibited more (P < 0.05) structures with irregular lamin (72%) than control (9%). Vitrification of matured COCs did not induce abnormalities of meiotic spindle, compared to control matured (25% and 37%, respectively) (P > 0.05). The cleavage rate was higher (P < 0.05) in matured vitrified than immature vitrified group (19% vs. 8%). In conclusion, immature COCs were more tolerant to cryoprotectant exposure. However, matured oocytes showed better embryo development (cleavage) after vitrification.

Background The economic consequences from mortality of sheep after blood loss can be considerable. To date there are no reports addressing hematologic, blood gas, and biochemical changes in ovine blood stored in CPDA-1 bags. Objectives The aim of this study was to investigate hematologic, blood gas, and biochemical alterations resulting from storage of ovine blood in CPDA-1 bags to establish transfusion protocols in sheep. Methods From each of 7 healthy 8-month-old sheep 450 mL of blood were collected into CPDA-1 bags and stored for 35 days in at 3–6°C. Samples were taken from the bags at days 0, 7, 14, 21, and 35. Whole blood was used to assess PCV, MCV, RBC count, pH, pO2, pCO2, and concentrations of bicarbonate, sodium, and lactate. Plasma was used to measure potassium, hemoglobin, and glucose concentrations. Results The PCV remained stable throughout the storage period, while plasma hemoglobin and MCV began to increase on days 7 and 21, respectively. The RBC count began to decrease on day 21. Blood pH decreased and pCO2 increased steadily throughout the storage period. Potassium concentration increased from 3.8 to 18.3 mmol/L on day 7 and remained high thereafter. In contrast, sodium concentration began to decrease on day 7. Conclusions The results show that ovine blood undergoes hematologic, blood gas, and biochemical changes during storage. Further studies are required to establish RBC viability in CPDA-1 bags after a storage period of 35 days.

An outbreak of enzootic ataxia among sheep raised in the northeastern region of Brazil is described. Copper (Cu) deficiency was diagnosed in a herd of 56 sheep, among which five presented characteristic clinical symptoms of enzootic ataxia. The symptoms began 30 days after birth, with a clinical condition that included locomotion difficulty, limb ataxia, tremors, and continual falls. Liver biopsies were performed and blood was collected to determine hepatic and plasmatic Cu, iron (Fe), and zinc (Zn) concentration, respectively. The laboratory results showed that the animals presented low copper concentrations in the plasma and liver, without difference between the clinically healthy animals and those affected by enzootic ataxia. Even after supplementation with adequate Cu levels had been recommended, it was found on a new visit to the farm four months later that one animal still presented a clinical condition and that the hepatic Cu levels of the herd had not risen. Despite the low copper content of the diet, the high hepatic Fe levels found suggest that antagonism due to this element may have been an important factor in triggering copper deficiency in these animals, and thus, additional copper supplementation may be necessary for these animals.

Background This study aimed to evaluate the clinical, haematological and biochemical responses to autologous blood transfusion and the feasibility of this practice in sheep. Thus, we used eight male, 8 months old sheep, weighing on average 30 kg, from which 15 mL/kg of whole blood was collected and stored in CPDA-1 bags. Blood samples were refrigerated for 8 days and subsequently re-infused. The clinical, haematological and biochemical parameters were evaluated before blood collection and reinfusion, after 10 minutes of collection and reinfusion, after 3, 6, 12, 24, 48, 96 and 192 hours after collection and reinfusion. Results With respect to clinical parameters, we observed a decrease in heart rate after 24, 48 and 196 hours from reinfusion compared to basal values (p p p p Conclusion Autologous transfusion in sheep slightly altered the physiological, biochemical and haematological responses of sheep, indicating that the technique proposed is safe and can be applied in the clinical practice of this species. The 8 d period was not sufficient for complete recovery of the haematological parameters after blood collection.