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611.
The aim of this study was to describe the microstructure of hoof capsules of the buffalo. In addition, the study emphasized the morphometric aspects of the horn tubules, the Vickers nanohardness of the dorsal and abaxial walls and sole of the digits of the thoracic and pelvic limbs of the buffalo. The abaxial wall in the thoracic and pelvic digits showed larger diameter of the horn tubules when compared to all dorsal wall and sole. In addition, the abaxial wall of the thoracic digits showed larger diameter of the horn tubules when compared with the pelvic digits. According to the three‐dimensional microtomography, the dorsal wall was higher in density compared with the abaxial wall. The latter exhibited an intermediate density, while the sole showed the lowest density. The Vickers nanohardness test showed that there was no difference in hardness and resistance between the experienced regions. However, the elastic modulus was greater on the transversal section of the hoof capsule. In conclusion, the results of the current study show that modern technologies such as microtomography and subsequent imaging can be used to investigate details of the basic morphology in different regions of the buffalo's hoof.  相似文献   
612.
Bronchoalveolar lavage (BAL) is a procedure that retrieves cells and other elements from the lungs for evaluation, which helps in the diagnosis of many pulmonary diseases. The aims of this work were to perform this procedure in dogs in the acute and chronic phases of an Angiostrongylus vasorum infection for cytological analysis and to evaluate the potential of this technique as a diagnostic method for this lung-heart worm. The BAL procedure was performed through the use of an endotracheal tube on seven A. vasorum infected dogs and on five non-infected dogs lined as a control group. Sixty days post-infection (dpi) active and live larvae were retrieved from the bronchoalveolar fluid (BALF) of all infected dogs. Furthermore, in one animal it was possible to retrieve larvae in its BALF before the pre-patent period. This work reports that the A. vasorum infection resulted in an increase of relative neutrophils and eosinophils counts. In contrast, there was a significant decrease in the alveolar macrophage relative count in infected animals from 60 to 330 dpi. This study shows that the BAL is an accurate technique for the diagnosis of canine angiostrongylosis. Moreover, the technique allows us to retrieve cells and other elements that line the lung surface for cytological evaluation, which provides information about inflammatory diseases, and the diagnosis and prognosis of pulmonary parasites such as A. vasorum.  相似文献   
613.
Objective To compare the magnitude and duration of the peri‐operative haematological, endocrine and metabolic effects of surgery performed under sevoflurane anaesthesia. Study Design Prospective randomized study. Animals Ten, 55‐day‐old lambs of both sexes, mean weight 20.8 ± 0.3 kg (range 18.5–23.6 kg). Methods Animals were randomly allocated to two equal groups. All were anaesthetized with sevoflurane for 3 hours. Surgery (end‐to‐end anastomosis of the right carotid artery and right jugular vein) was performed in animals of Group 1 only. The electrocardiogram, pulse oximetry, cardiac output and noninvasive arterial blood pressure (NIBP) were monitored. Venous blood samples (5 mL) were taken 30 minutes before induction of anaesthesia (T = 0) and 1 (T1), 24 (T2), 48 hours (T3) and 7 days (T4) after anaesthesia in order to measure plasma cortisol, ACTH, insulin, cyclic adenosine monophosphate (cAMP), glucose, protein concentrations and haematological variables. Results Sevoflurane decreased NIBP (minimum mean value: 64 ± 3 mm Hg) in both groups. Plasma cortisol and ACTH concentration increased in Group 1 (maximum mean values: cortisol: 136.2 nmol L?1, ACTH: 54.5 pmol L?1) and Group 2 (maximum mean values: cortisol: 128.7 nmol L?1, ACTH: 44.0 pmol L?1). Cyclic AMP increased only in Group 1 (9.3 nmol) 1 hour after anaesthesia. Neutrophilia, lymphopaenia and a decreased PCV were observed in both groups 1 hour after anaesthesia. Plasma protein and glucose concentrations did not change. Conclusions Increased ACTH and cortisol concentrations recorded 1 hour after anaesthesia suggest that sevoflurane induces a stress response in lambs. Clinical relevance The study did not identify the mechanism by which sevoflurane induces a stress response although hypotension is implicated.  相似文献   
614.
An immunoenzymatic assay (ELISA), an indirect immunofluorescence antibody test (IFAT) with different antigens (ELISA-Leishmania chagasi, ELISA-L. major-like, IFAT-L. chagasi and IFAT-L. major-like), and an immunochromatographic test were assessed for the diagnosis of canine visceral leishmaniasis (CVL). Serum samples from 144 dogs from an endemic area for visceral leishmaniasis in the municipality of Rio de Janeiro were tested. The sensitivities of the serological tests were 93%, 100%, 73%, 60% and 93%, with specificities of 87%, 92%, 77%, 96% and 92% for the ELISA-L. major-like, ELISA-L. chagasi, IFAT-L. major-like, IFAT-L. chagasi and the immuno chromatographic test, respectively. ELISA-L. chagasi was the best test for the diagnosis of CVL, but the immunochromatographic test could be a useful alternative as it offers simple and rapid diagnosis without the need for a specialized laboratory.  相似文献   
615.
An ideal amino acid ratio (IAAR) for breeder hens is needed for maximum nitrogen retention (NR) taking into account nitrogen deposition in body (NDB), feathers (NDF) and egg mass (NEM) to improve dietary protein efficiency. Thus, the aim of this study was to apply the deletion method to derive the IAAR for broiler breeder hens. The nitrogen balance trials were performed from 31 to 35 weeks and from 46 to 50 weeks. Twelve treatments with eight replicates and one hen per cage were used. A balanced diet (BD) was formulated to meet the requirement of all nutrients. The other diets were formulated diluting 55% of BD with corn starch and refilled with amino acids (AAs) and other ingredients, except the AA tested. Each trial lasted 25 days. Feather losses, egg production and egg weight were recorded daily, and the samples were stored to further determine NEM and nitrogen in feather losses (NDFL). At the start and the end of each period, a group of birds were slaughtered to further determine NDB and NDF. The NR was calculated as the sum of NDB, NDF, NDFL, NEM and the nitrogen maintenance requirement (NMR). The deletion of valine greatly depressed the NR in peak production (31 to 35 weeks) while the deletion of the isoleucine greatly depressed the NR of the hens from 46 to 50 weeks of age. The percentual reduction in NR and the per cent of the AA to delete from the BD were used to calculate the AA requirement. The average IAAR was Lys 100, Met+Cys 86, Trp 23, Thr 80, Arg 113, Val 90, Ile 91, Leu 133, Phe+Tyr 108, Gly+Ser 94 and His 35. The IAAR was in line with the recommendation from the literature, validating deletion method with the advantages from a rapid and low‐cost procedure.  相似文献   
616.
617.
This study describes the morphometry of the testicles of captive coatis (Nasua nasua) and verifies the existence of correlations between the testicles and the semen producing characteristics. Twelve ejaculates were obtained from five adult specimens that were restraint by anaesthesia. Visual and morphometric evaluation of the external genitalia was performed by using a caliper. The animals presented a scrotal circumference of 9.4 ± 0.7 cm. The right testicle presented a width of 1.7 ± 0.2 cm, length of 2.6 ± 0.2 cm and volume of 3.9 ± 1.1 cm3. The left testicle presented a width of 1.7 ± 0.1 cm, length of 2.5 ± 0.3 cm and volume of 3.6 ± 0.7 cm3. No significant correlations were obtained between the scrotal circumference or total testicular volume and the semen producing characteristics (volume and sperm concentration). For the first time in this field, this study presents an important contribution to the knowledge of the reproductive morphophysiology of coatis.  相似文献   
618.
Because of the high incidence of thromboembolic diseases in humans, experimental models of thrombosis have been widely developed in different animal species. The pathogenesis of thrombosis is associated with three components, first outlined by Virchow in 1856: vessel injury, stasis, and hypercoagulability. Based on this concept, the purpose of the present investigation was to create an innovative model of jugular thrombophlebitis in horses that included components of Virchow's triad and excluded surgical procedures. Eighteen horses were subjected to blood vessel injury through the coadministration of sclerosing agents (glucose and ethanolamine oleate) and transitory occlusion of the jugular flow by manual compression. Thrombus formation was followed by ultrasonography imaging, and all horses developed jugular thrombophlebitis, showing that the proposed model was effective. Once occlusive thrombophlebitis was induced, jugular venous pressure cranial to the lesion was evaluated and yielded increased values, suggesting cephalic hypertension. Biochemical tests were performed to verify hepatotoxicity and nephrotoxicity after the ethanolamine injection, but no abnormalities were observed. Five horses were then euthanized to evaluate the vascular, hepatic, and renal tissues. The jugular vein wall had increased thickness, inflammatory cell influx, endothelial destruction, and thrombus firmly adhered to the vessel intima. Histological evaluation of the hepatic and renal tissues was normal. The present thrombophlebitis model in the jugular vein of the horse is simple and reproducible, providing a useful tool for investigating acute and chronic venous thrombosis because the model allows evaluation of different aspects of the prevention, pathogenesis, and treatment of this disease.  相似文献   
619.
Veterinary Research Communications - The aim of this study was evaluating the association and correlation between the diagnostics tests used for Leishmania spp. detection in dogs and ticks. We...  相似文献   
620.
The objective of this study was to assess parameters of sexual behavior, seminal characteristics, testicular measurements, and their correlations in Piau boars. A total of 169 observations of the sexual behavior and prelude duration (courting) of 10 Piau boars aged from 0.8 to 6.4 years were made; semen was also collected from these animals. The testicular length (TL), testicular width (TW), testicular shape (TS; 1-5), and testicular volume (TV) of these animals were measured. The seminal physical and morphological characteristics of 60 ejaculates from 6 boars were assessed for volume of ejaculate (VOL), volume of the gelatinous portion (VOLGEL), aspect (ASP), sperm motility (MOT), spermatic vigor (VIG), spermatic concentration per milliliter (CONCML), total concentration (CONCT), and morphological characteristics (major defects [MAJDEF]; minor defects [MINDEF]; and total defects [TDEF]). The animals were subdivided into 3 age groups: G1 (0.8-2.0 years old), G2 (2.1-3.6 years old), and G3 (3.7 and 6.4 years olds). The physiological signs observed included duration of prelude (12.1 ± 4.1 minutes), time to collect semen (5.2 ± 1.8 minutes), nasonasal or genital contact behavior (71.6%), saliva emission (85.2%), urination during prelude (10.1%), penile exposure before collection (26.6%), flank stimulus (81.7%), chewing behavior (95.3%), and biting of the female or dummy (74.6%). The mean values of TL, TW, and TV were 11.8 ± 2.2 cm, 6.2 ± 1.3 cm and 754.1 ± 283.5 cm3, respectively. The older animals had the highest mean values of testicular measurements (P < 0.05) but the lowest mean values of CONCML and CONCT (P < 0.05). All the animals presented similar patterns of ejaculates (P > 0.05); the mean values of VOL, VOLGEL, MOT, VIG, and CONCT were 149.1 ± 51.1 mL, 29.7 ± 10.0 g, 76.2% ± 9.5%, 3.3 ± 0.5, and 29.4 ± 19.5 × 109 total sperm in the ejaculate, respectively. The prevalence rates of defects were 5.9% ± 2.6% for MAJDEF, 10.2% ± 4.0% for MINDEF, and 16.2% ± 5.5% for TDEF; all animals were classified as being sound for breeding. The assessed characteristics were similar to those observed in swine of commercial lineages and within the standards established by the Brazilian College of Animal Reproduction for the species.  相似文献   
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