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排序方式: 共有173条查询结果,搜索用时 218 毫秒
61.
Gabriela Bertaiolli Zoca Eneiva Carla Carvalho Celeghini Guilherme Pugliesi Carla Patricia Teodoro de Carvalho Mayra Elena Ortiz D'Avila Assumpção Adriano Felipe Perez Siqueira Leticia Zoccolaro Oliveira Renata Lançoni Rubens Paes de Arruda 《Reproduction in domestic animals》2021,56(6):872-883
This study aimed to evaluate the effect of seminal plasma on bovine sperm cryopreservation and to assess the integrity of plasma and acrosomal membranes, mitochondrial potential, remodelling of F-actin cytoskeleton and sperm chromatin fragmentation during the cooling, equilibrium and freezing/thawing stages. Six ejaculates collected from seven Nelore bulls (n = 42) were used in this study. Each ejaculate was divided into two aliquots (with seminal plasma = SP group; without seminal plasma = NSP group) and packed to a final concentration of 50 × 106 sperm per straw. Statistical analyses were performed using SAS software (version 9.3), and p ≤ .05 was considered significant. A time effect was observed for all sperm characteristics (p < .05), except for chromatin fragmentation (p > .05). The presence of seminal plasma better preserved the acrosomal integrity (SP = 75.2% and NSP = 71.7%; p < .05) and also provided lower F-actin remodelling during cryopreservation process (SP = 29.9% and NSP = 32.4%; p < .05). Regarding to the cryopreservation stages, it was observed that cooling step induced higher remodelling of F-actin than the equilibrium and freezing/thawing stages (56.3%, 32.2% and 23.9%, respectively; p < .05). The equilibrium step had minor influence on overall sperm characteristics while the freezing/thawing stage was responsible for the highest percentage of damage in plasma membrane (−65.2%), acrosomal membrane (−34.0%) and mitochondrial potential (−48.1%). On the other hand, none of the cryopreservation stages affected chromatin integrity. It was concluded that the presence of seminal plasma provides increased acrosomal integrity and reduced remodelling of F-actin cytoskeleton. Higher F-actin remodelling is observed after the cooling step while the freezing/thawing step is most damaging to sperm membranes and mitochondrial potential during bovine sperm cryopreservation. 相似文献
62.
Monção Flávio Pinto Costa Marco Aurélio Morais Soares Rigueira João Paulo Sampaio de Sales Eleuza Clarete Junqueira Leal Dijair Barbosa da Silva Marcos Felipe Pereira Gomes Virgílio Mesquita Chamone Julieta Maria Alencar Alves Dorismar David da Cunha Siqueira Carvalho Cinara Murta José Eduardo Jardim Júnior Vicente Ribeiro Rocha 《Tropical animal health and production》2020,52(1):235-241
Tropical Animal Health and Production - The objective of this study was to evaluate the productivity, productive efficiency, and nutritional value of the elephant grass cultivar BRS capiaçu... 相似文献
63.
de Carvalho MA Santos PS Nogueira SS Lessa F Almeida Vdos A Le?a-Júnior NF Salvarani FM Lobato FC Nogueira-Filho SL 《Journal of zoo and wildlife medicine》2011,42(4):732-734
An outbreak of necrotic enteritis caused by Clostridium perfringens type C was diagnosed in captive collared (Pecari tajacu) and white-lipped (Tayassu pecari) peccaries housed in the Laboratory of Applied Ethology of Universidade Estadual de Santa Cruz located in Ilhéus, State of Bahia, Brazil. Four collared peccaries and three white-lipped peccaries, all juveniles (25-105 days old), were affected. For all affected animals, lethargy and inappetance were followed by sudden death within 24 hours. Histopathology of intestinal wall, culture of C. perfringens type C, and the identification of beta-toxin from intestinal content confirmed the diagnosis. 相似文献
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This paper describes the reproductive performance of Penueus schmitti kept under controlled conditions in a maturation facility of a commercial shrimp farm. A total of 369 females and 368 males of wild P. schmitti were used to form 9 broodstock groups. Unilateral ablation was performed on females only. Although females were not tagged, the total number of mated females ( N = 533) indicates that rematuration of the ovaries did occur. Only 9 mated females (1.69%) did not spawn and only 22 mated females (4.20%) of the remaining 524 cases did not produce viable spawns. These results indicate that a large number of viable spawns (94.18%) can be expected from P. schmitti . A minimum latency period of 6 days for the ovaries to attain full development was observed twice. The highest mating frequency occurred between the 46th and 60th days after unilateral ablation, but mating frequency remained above 2% until the 90th day. The average number of nauplii/female/spawn was 78,961 ( N = 524) and the average fertilization rate of the eggs was 73.12% ( N = 297). Usually when the pair of the spermatophores is dislodged from the thelycum of the mated female, a small sperm mass still remains between the third pair of walking legs. This condition did not show any negative effect on the fertilization rate of the eggs and nauplii production. Mating behavior displayed by P. schmitti is also described and includes three distinctive phases: a) chasing, b) mating and c) post-mating chase. 相似文献
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68.
NCG Pieri AF Souza JB Casals KCS Roballo CE Ambrósio DS Martins 《Reproduction in domestic animals》2015,50(4):625-631
The precise determination of the embryonic chronology is very important in reproductive biotechnologies, especially in estimating embryonic age. Thus, there is a need for greater knowledge and standardization for determining the chronology of embryonic development and functional morphology. We describe aspects of embryonic development in two domestic carnivores to add knowledge about organ peculiarities and for application in veterinary practice, in prenatal development and in the biotechnology fields. We found that the development of differential characteristics of embryonic organs occurs in the first trimester of pregnancy for both species. Thus, using the combination of the crown‐rump length, macroscopic analysis and optical microscopy, it is possible to predict gestational age more precisely in animals that lack a defined breed and establish an embryonic pattern. 相似文献
69.
Marcela Pacola Tiara Moraes Guimarães João Paulo Gonsiorkiewicz Rigon Lucas Moraes Jacomassi João William Bossolani Josiane Viveiros Gabriela Ferraz de Siqueira Patrícia Pereira Dias Juliano Carlos Calonego Carlos Alexandre Costa Crusciol 《Soil Use and Management》2023,39(4):1388-1402
Combining deep tillage (DT) with lime application at greater depths may improve sugarcane yield. The objective of this study was to evaluate the impact of conventional tillage (CT) and DT systems and liming on sugarcane productivity and soil physical attributes. The experiment was conducted in a clayey-textured Rhodic Hapludox soil cultivated with sugarcane for two growing seasons (first and third ratoons) using a randomized block design with four treatments and four repetitions. The treatments consisted of DT without liming (DT0), DT with liming (DT2), CT without liming (CT0) and CT with liming (CT2). In addition to sugarcane stalk and sugar yields, macroporosity (MA), microporosity (MI), total soil porosity (TP), weighted average diameter (WAD), aggregate stability index (ASI), soil penetration resistance (SPR), pH, potential acidity (H + Al), total soil organic carbon (SOC), particulate organic carbon (POC), mineral-associated organic carbon (MOC), calcium (Ca) and magnesium (Mg) were analysed. DT2 promoted the best soil conservation effect on sugarcane. In general, DT, regardless of lime application, reduced SOC and POC in soil surface layer. Nevertheless, in the long term, localized lime addition resulted in significant reductions in compaction, reaching values below 2 MPa. The soil fertility improvement provided by DT2 promoted increased sucrose concentrations and stalks yield. Considering that there was an improvement in the physical quality and fertility of soil for better plant development, the deep tillage with localized lime addition can be considered an effective alternative for sugarcane cultivation. 相似文献
70.
Abstract CASE HISTORY: A 2-year-old Hereford bull was lame for one week before becoming recumbent. CLINICAL AND PATHOLOGICAL FINDINGS: The scrotum and ventral perineal region were cold and blackened caudally. The semimembranosus and semitendinosus muscles were firm on palpation. The bull was subject to euthanasia, and necropsy revealed that the skin and S/C tissues of the caudal half of the scrotum were grey and necrotic. The caudal and distal aspects of the semimembranosus and semitendinosus muscles were grey and necrotic to a depth of approximately 15 cm, and these changes appeared to track along fascial planes. The tissue had an offensive smell, and large amounts of flocculent, watery, brown fluid and some gas were present. Histology of affected muscle and S/C tissues revealed coagulative necrosis, with oedema and large numbers of bacteria that were predominantly Gram-positive rods. Adjacent blood vessels contained thrombi while the epidermis overlying the affected areas appeared diffusely necrotic, suggesting infarction. Culture of the fluid yielded a pure growth of Arcanobacterium spp., which was identified as Arcanobacterium haemolyticum, using an API Coryne biochemical test strip. DIAGNOSIS: Necrotising fasciitis and myositis due to Arcanobacterium haemolyticum. CLINICAL RELEVANCE: Arcanobacterium haemolyticum has not previously been reported as a cause of necrotising fasciitis in any species. Necrotising fasciitis is probably an under-reported condition in cattle due to its clinical similarity to clostridial disease. 相似文献