RESUMO
The aim of this study was to evaluate two cryoprotectants, dimethylformamide (DMF) and methylformamide (MF) in two concentrations (5 and 7 %) in vitro in donkey semen using a rapid freezing technique and the effect on pregnancy rates in mares. Twenty-four ejaculates from 8 jacks (n = 8; r = 3) were divided into 4 extenders: BotuSemen Gold with 5 % or 7 % MF and 5 % or 7 % DMF, all containing 11 % lactose, 20 % egg-yolk and 0.5 % Equex. Post-thaw evaluations included: sperm motility, membrane function and acrosome status. A linear mixed effect model was used to test the effect of different freezing media on semen parameters. No differences were observed between the 4 freezing media used, for any of the seminal parameters (P > 0.05). However, samples with 5 % DMF showed the highest percentages of sperm with acrosomes and functional membranes (DMF: 5 %: 53.67 ± 22.01; 7 %: 33.92 ± 23.4; MF: 5 %: 44.5 ± 20.46; 7 %: 38.75 ± 27.4) (Data: mean ± SD; P > 0.05). Hence, thirty mares were inseminated: 15 with 5 % DMF and 15 with 7 % DMF. The pregnancy rate was 46 % (7/15) and 0 % (0/15) using the extender with 5 % or 7 % DMF, respectively (P = 0.003). To conclude, the use of 5 % or 7 % of MF or DMF did not affect the in vitro parameters. Despite the lack of differences in vitro with the two DMF concentrations, in vivo results only showed pregnancies when using 5 % DMF. Thus, the results of this study demonstrate the importance of accompanying in vitro semen evaluations with studies that evaluate post-insemination pregnancy rates.
Assuntos
Criopreservação , Crioprotetores , Equidae , Preservação do Sêmen , Animais , Equidae/fisiologia , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Crioprotetores/farmacologia , Feminino , Masculino , Criopreservação/métodos , Criopreservação/veterinária , Gravidez , Dimetilformamida/farmacologia , Inseminação Artificial/veterinária , Sêmen/efeitos dos fármacos , Sêmen/química , Motilidade dos Espermatozoides/efeitos dos fármacos , FormamidasAssuntos
Antineoplásicos Imunológicos/efeitos adversos , Inibidores de Checkpoint Imunológico/efeitos adversos , Nivolumabe/efeitos adversos , Neoplasias Cutâneas/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Idoso , Anticorpos Antinucleares/análise , Quimiorradioterapia/métodos , Progressão da Doença , Humanos , Imunoterapia , Masculino , Reumatologistas , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologiaRESUMO
A herd of 135 Aberdeen Angus cows were grazing on pastures containing abundant Senecio selloi in the eastern region of Buenos Aires Province, Argentina. Some undiagnosed deaths were observed during 1989. In 1990 the death count raised to 38 animals, all of them showing the same clinical signs and gross and histopathological lesions. The time from the start of signs to death varied from 2 to 6 d. The most conspicuous signs were distention of the abdominal cavity and moderate icterus of mucous membranes. At necropsy, large amounts of fluid were in the abdominal cavity, there were lesions in the digestive tract, kidneys and mesenteric lymph nodes, and the liver was enlarged and fibrous. Histopathology showed the hepatic parenchyma replaced by fibrous tissue with marked megalocytosis. The signs and lesions were consistent with those produced by pyrrolizidine alkaloids. An abundance of Senecio selloi resulted in a diagnosis of poisoning from this plant. This is the first report of toxicity due to this plant species in Argentina.