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Owing to a drastic decline in the population of wild cats and a growing interest among cat breeders, the development of assisted reproductive techniques for felines has been an important subject of research over the last decade. In this paper we describe the present state of knowledge and prospects for development in this field. The paper is divided into sections dealing with the collection and preservation of semen, artificial insemination, oocyte collection, in vitro fertilization and cryopreservation of eggs. The paper also discusses the apoptotic events occurring in gametes, which are crucial for the development of assisted reproductive techniques.
This paper presents the neurohormonal regulation of the oestrus cycle in bitches, with particular emphasis on the luteal phase. The authors described specific features of the oestrus cycle in the female of the domestic dog, such as the lack of maternal recognition of pregnancy and no acute luteolytic mechanism in the absence of pregnancy, which result in very similar hormonal profiles of pregnant and non-pregnant bitches. The authors presented the mechanism of transition from anoestrus to proestrus and the mechanism that causes follicular development, eventually leading to ovulation. In this paper the luteal phase was divided into the early luteal phase, mid-luteal phase, and regression phase. The mechanism of pre-partum luteolysis and the role of other non-hormonal factors were also described.
Until recently, assessment of sperm quality was based on subjective evaluation of parameters such as semen concentration, motility and morphological abnormalities. These methods are influenced by many factors: temperature, evaluator skills and experience, the number of evaluated spermatozoa, difference in sample preparation, etc. Consequently high variations were reported in the estimation of semen quality of the same ejaculate assessed by different observers. Computer assisted semen analysis (CASA), based on individual spermatozoon assessment, offer an accurate and rapid calculation of different semen parameters, such as total motility, progressive motility, linearity, several velocity parameters and morphology. The development and problems related to using CASA technology are raised in this review.
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