Estudos preliminares sobre as características de carcaça de ovinos deslanados do nordeste semi-árido do Brasil

This experiment was carried out to evaluate the potentiality of meal production in male lambs of three indigenous breeds of hairy (woolless) sheep maintained on native "caatinga" pastures up to six or seven months of age, and, if necessary, under stall-feeding subsequently, in the hot tropical Northeast Brazil. The results showed that the optimum slaughter weight of 25 kg was reached in Santa Inês and some of the Morada Nova lambs on native pastures by the time they were six to seven months of age. Some other twin-born lambs of Morada Nova and all lambs of Brazilian Somali breeds did not reach the weight till seven months of age and these animals had to be stall-fed for additional period. These reached the optimum slaughter weight at around nine to ten months of age. Thus, Santa Inês breed had the best growth, Morada Nova was intermediate and Brazilian Somali had the minimum growth. These breed differences, which reflect their adult body sues, also influenced some of the carcass characteristics. The type of birth appeared to have a marked effect on size, growth and some of the carcass characteristics. Single-born lambs had a distinct advantage. There was virtually no difference in the carcass characteristics of older and younger lambs of comparable weights and it appeared that these traits were related more to the weight of lamb at slaughter.Este experimento foi conduzido na região do Sertão no nordeste do Brasil, para avaliar a potencialidade de produção de carne, em ovinos de raças deslanadas, mantidos em pastagens nativas, de caatinga, até os seis ou sete meses de idade, e depois, se necessário, em confinamento. Os resultados demonstraram que o peso de abate (25 kg) foi alcançado em pastagem nativa com os animais da raça Santa Inês e alguns da raça Morada Nova, antes dos sete meses de idade. Alguns cordeiros gêmeos da raça Morada Nova e todos os da Somalis Brasileira não atingiram o peso de abate até os seis ou sete meses de idade e foi necessário o seu confinamento por um período adicional de dois a três meses. A raça Santa Inês apresentou a maior velocidade de crescimento, enquanto que a Somalis, a menor. A raça Morada Nova situou-se em posição intermediária. Essas diferenças entre raças refletem o tamanho corporal à idade adulta e também influenciaram algumas características de carcaça. O tipo de nascimento parece ter efeito signicativo no tamanho, no crescimento e em algumas características de carcaça. Cordeiros nascidos como únicos foram superiores aos gêmeos. Não foi observada nenhuma diferença nas características de carcaça entre os animais de idades diferentes e pesos semelhantes. Parece que essas características são mais relacionadas com o peso do cordeiro ao abate

Is the right testis more affected by cryptorchidism than the left testis? An ultrasonographic approach in dogs of different sizes and breeds

Background: Considered the most common congenital testicular abnormality of companion animals and a predisposition factor to the development of testicular neoplasia, cryptorchidism is defined as the non-descent of one or both testes to their normal anatomical location. Data on the occurrence of cryptorchidism in Brazil are scarce. The purpose of this work was to verify the occurrence of cryptorchidism in dogs of different sizes and breeds. Materials and methods: Cryptorchidism identification was carried out by ultrasound scanning, from November, 1994 to March, 2007, at the Centre for Veterinarian Diagnosis and Support (Centro de Apoio e Diagnóstico Veterinário — CAD), in Rio de Janeiro. 4924 male dogs of different breeds were examined, revealing 403 (8.2%) cryptorchidism. Results: In this study, occurrence took place more often on the right testicle (59.5%), more frequently displaying inguinal localisation (59.5%) and unilateral occurrence (70%). Regarding bilateral presentation, the symmetrical form was the most common (86.8%). Cryptorchidism was more common in the inguinal region of dog of small sized breeds and in the abdominal region in dogs of medium- and large-sized breeds. Conclusions: Ultrasound scan proved a valuable diagnosis tool for cryptorchid testes, giving precise localisation and parenchymal changes thus leading to a safe clinical treatment

Variational approach to a class of nonlinear oscillators with several limit cycles

We study limit cycles of nonlinear oscillators described by the equation $\ddot x + \nu F(\dot x) + x =0$. Depending on the nonlinearity this equation may exhibit different number of limit cycles. We show that limit cycles correspond to relative extrema of a certain functional. Analytical results in the limits $\nu ->0$ and $\nu -> \infty$ are in agreement with previously known criteria. For intermediate $\nu$ numerical determination of the limit cycles can be obtained.Comment: 12 pages, 3 figure

Gamma-irradiated human amniotic membrane decellularised with sodium dodecyl sulfate is a more efficient substrate for the ex vivo expansion of limbal stem cells

yesThe gold standard substrate for the ex vivo expansion of human limbal stem cells (LSCs) remains the human amniotic membrane (HAM) but this is not a defined substrate and is subject to biological variabil-ity and the potential to transmit disease. To better define HAM and mitigate the risk of disease transmis-sion, we sought to determine if decellularisation and/or c-irradiation have an adverse effect on culture growth and LSC phenotype. Ex vivo limbal explant cultures were set up on fresh HAM, HAM decellularised with 0.5 M NaOH, and 0.5% (w/v) sodium dodecyl sulfate (SDS) with or without c-irradiation. Explant growth rate was measured and LSC phenotype was characterised by histology, immunostaining and qRT-PCR (ABCG2, DNp63, Ki67, CK12, and CK13). Ƴ-irradiation marginally stiffened HAM, as measured by Brillouin spectromicroscopy. HAM stiffness and c-irradiation did not significantly affect the LSC phe-notype, however LSCs expanded significantly faster on Ƴ-irradiated SDS decellularised HAM (p < 0.05) which was also corroborated by the highest expression of Ki67 and putative LSC marker, ABCG2. Colony forming efficiency assays showed a greater yield and proportion of holoclones in cells cultured on Ƴ-irradiated SDS decellularised HAM. Together our data indicate that SDS decellularised HAM may be a more efficacious substrate for the expansion of LSCs and the use of a c-irradiated HAM allows the user to start the manufacturing process with a sterile substrate, potentially making it safer