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1.
Theriogenology ; 126: 286-294, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597387

RESUMO

The objective of the study was to understand the influence of climatic variations in a semiarid environment on serum testosterone, testicular morphology and semen quality in collared peccaries (Pecari tajacu). Reproductive metrics (semen quality, testicular morphometry and testosterone serum profiles) of 10 mature males were measured monthly for 18 months. Meteorological data (rainfall, air temperature, relative humidity, wind speed and radiant heat load) also were recorded during the same period. Rainfall regimes were classified in different classes (Class 1: months with no rain; Class 2: months with up to 50 mm of rain; and Class 3: months with >50 mm of rain). Among rainfall classes, average air temperature (°C) and relative humidity (%) were different. Climatic changes between rainfall classes did not lead to overall variations of testicular size, testosterone production, and semen metrics. However, relative humidity recorded before semen collection (one day, one week, or over 51-55 days) was positively correlated (P < 0.05) with semen motility metrics (total motility, beat cross frequency and straightness) and sperm subpopulations (medium and static sperm), as well as with volume. Negative correlations (P < 0.05) were revealed between air temperature and the same semen motility patterns and volume. Additionally, radiant head load measured on the day of semen collection negatively influenced (P < 0.05) sperm straightness. This study demonstrates for the first time that no seasonal changes could be detected overt the 18-month period on the serum testosterone, testicular morphology and semen quality of collared peccaries raised in the Caatinga biome; however, it is expected that long term environmental changes will influence the reproductive physiology of species leaving in that habitat.


Assuntos
Clima , Mamíferos/fisiologia , Análise do Sêmen/veterinária , Testículo/anatomia & histologia , Testosterona/sangue , Animais , Temperatura Corporal , Umidade , Masculino , Chuva , Estações do Ano , Temperatura
2.
Theriogenology ; 74(1): 146-52, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20207405

RESUMO

The objective was to investigate the use of powdered coconut water (ACP)-based medium for short-term preservation of canine preantral follicles. Pairs of ovaries from mongrel bitches (n=9) were divided into fragments. One ovarian fragment, treated as a fresh control, was immediately fixed for histological analysis, whereas the other six ovarian fragments were stored either in phosphate-buffered saline (PBS; control group) or ACP medium in isothermal Styrofoam boxes containing biological ice packs. The boxes were sealed and opened only after 12, 24, or 36h. After opening each box, the ovarian fragments were submitted to histological analysis. In total, 12,302 preantral follicles were evaluated, with 64.5% primordial, 33.3% primary, and 2.3% secondary follicles. There were multiple oocytes in 1.3% of the follicles analyzed. At 24h, ACP was more efficient in preserving follicular morphology than PBS (P<0.05). Compared with the fresh control group, a significant reduction in the percentage of morphologically normal ovarian follicles was observed for PBS, starting at 24h; however, the decline started only at 36h for the ACP medium. During the experiment, the temperature inside the isothermal boxes increased from 3 to 9 degrees C (P<0.05), despite a constant room temperature. In conclusion, powdered coconut water (ACP) was an appropriate medium for short-term storage of canine preantral ovarian follicles.


Assuntos
Cocos , Cães , Folículo Ovariano/fisiologia , Preservação de Tecido/veterinária , Animais , Temperatura Baixa , Feminino , Frutas , Células da Granulosa/ultraestrutura , Oócitos/ultraestrutura , Folículo Ovariano/citologia , Soluções , Fatores de Tempo , Preservação de Tecido/métodos , Água
3.
Anim Reprod Sci ; 118(2-4): 362-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19748749

RESUMO

The aim of this study is to describe the characteristics of the semen from six-banded armadillos (Euphractus sexcinctus) collected by electroejaculation. Six mature males were physically restrained and electroejaculated twice for the collection of semen. Semen collected was immediately evaluated for appearance, volume, pH, sperm motility, vigor, morphology, percentage of live sperm and functional membrane integrity by light microscopy. Semen was obtained from all (100%) twelve attempts conducted for electroejaculation. Armadillos' semen had a white-translucent appearance, and great viscosity. Mean values obtained in analysis of the semen were: 353+/-86 microl for volume, 9 for pH, 45+/-14 x 10(6)sperm/ml for concentration, 61+/-7% motile sperm with 2+/-0.2 for vigor, 55+/-7% live sperm, 86+/-2% morphologic normal sperm, and 46+/-6% functional membrane integrity. In conclusion, semen from six-banded armadillos can be efficiently obtained by electroejaculation. The characteristics of semen collected by electroejaculation in six-banded armadillos provide background information that may be useful for assisted breeding programs in the members of the Xenarthra family.


Assuntos
Tatus , Ejaculação , Sêmen/fisiologia , Espermatozoides/fisiologia , Coleta de Tecidos e Órgãos/veterinária , Animais , Cruzamento , Estimulação Elétrica , Concentração de Íons de Hidrogênio , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/anormalidades , Espermatozoides/ultraestrutura , Coleta de Tecidos e Órgãos/métodos , Viscosidade
4.
Theriogenology ; 72(5): 650-4, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19541362

RESUMO

The objective of this study was to compare the effects of dimethylformamide (DMF) and glycerol in canine (Canis lupus familiaris) semen cryopreservation based on postthaw motility and velocity evaluated by computer-assisted sperm analysis (CASA) and the effects on subjective progressive motility, percentage of live sperm, and plasma membrane functional integrity. The semen was diluted in two steps with an egg-yolk Tris extender containing 6% glycerol or DMF, frozen in 0.25-mL straws, and stored in liquid nitrogen. Immediately after thawing, samples were accessed for subjective sperm motility, sperm membrane functional integrity, percentage of live sperm, and evaluation by CASA. There were differences (P<0.05) between glycerol and DMF with regard to subjective progressive motility (43.1% vs. 21.5%), objective progressive motility (11.8% vs. 6.2%), velocity average pathway (31.1 vs. 23.1 microm/sec), and amplitude of lateral head (3.3 vs. 3.9 microm), which confirmed the efficiency of glycerol. In conclusion, objective analysis performed by CASA confirmed that no benefits were derived by using DMF to replace glycerol for cryopreservation of canine semen.


Assuntos
Criopreservação/métodos , Dimetilformamida/farmacologia , Cães , Glicerol/farmacologia , Preservação do Sêmen/métodos , Animais , Crioprotetores/farmacologia , Cães/fisiologia , Masculino , Análise do Sêmen , Espermatozoides/efeitos dos fármacos
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