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ABSTRACT: Semen collection and AI in the cat are still not routine procedures. The correlation between semen quality and fertility under natural conditions is a relatively unknown field in the cat. In the present study, functional in vitro tests, such as the ability to bind and penetrate the zona pellucida or to fertilize in vitro, were used to determine fertilizing ability of sperm cryopreserved with a practical and efficient freezing protocol previously developed in our laboratory. Semen was collected by electroejaculation, evaluated for motility and diluted with Tris-glucose-citrate egg-yolk extender supplemented with Equex STM paste (0.5% v/v). After equilibration and loading into 0.25 ml straws, semen was frozen at 3.85 degrees C/min. Frozen-thawed semen was co-cultured with in vitro matured cat oocytes. Penetration rate was recorded 30 h after in vitro fertilization and cleaved zygotes were cultured in vitro until day 7. A correlation was found between sperm motility index (SMI) after thawing and semen fertilizing ability (p<0.05). In conclusion, it was demonstrated that the post-thaw motility quality, expressed as SMI, of spermatozoa frozen using the protocol mentioned above can be considered an index of the sperm ability to penetrate in vitro matured oocytes.
Reproduction in Domestic Animals 04/2006; 41(2):137-41. · 1.36 Impact Factor
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Animal Reproduction Science 11/2005; 89(1-4):223-5. · 1.75 Impact Factor
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Animal Reproduction Science 11/2005; 89(1-4):284-5. · 1.75 Impact Factor
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Veterinary Research Communications 09/2004; 28 Suppl 1:165-8. · 0.82 Impact Factor
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ABSTRACT: In a previous study we observed that it is possible to reach the cervix in all queens with a 1 mm diameter probe only. So, we developed both a new technique and a catheter (1 mm diameter) to allow transcervical insemination [Zambelli and Castagnetti 2001]. The aims of this study were to investigate vaginal and cervical anatomic modifications during the various stages of the oestrus cycle and to test the previously described technique of transcervical catheterization during the various stages of the oestrus cycle. In experiment 1, silicon impression moulds were obtained from the reproductive tracts of 21 queens' cadavers and vaginal and cervical measures were taken. The results showed that there are some significant anatomic modifications during the various stages of the oestrus cycle in vaginal and cervical anatomy, principally related to the dorsal medial fold increase induced by the follicular phase. In experiment 2, transcervical catheterization was attempted in 95 queens at various stages of oestrus cycle both during reproductive and non-reproductive season. After catheterization, methylene blue solution was injected through the cervical catheter. Successful catheterization was assessed during surgery, when colour was observed in the uterine horns. It was possible to perform transcervical catheterization during non-reproductive season in 16 of 20 anoestrus queens and in 12 of 15 induced oestrus queens; during reproductive season in nine of 21 interoestrus queens, in eight of 13 dioestrus/pregnancy queens, in four of 18 oestrus queens and in seven of eight queens in first oestrus during lactation.
Reproduction in Domestic Animals 05/2004; 39(2):76-80. · 1.36 Impact Factor
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ABSTRACT: The first pregnancies in domestic cats were obtained using semen frozen in pellets (Platz et al. 1978). Other freezing methods, vials (Lengwinant and Blottner 1994) or straws (Pope et al. 1991; Hay and Goodrowe 1993), have also been used. Pelleted freezing has often been the standard method (Howard 1986). Opinions about the freezing method are discordant; the best method for Pope et al. (1991) was using straws; in fact, the post-thaw motility and the percentage of normal acrosomes were of 44 +/- 4 and 62 +/- 3%, respectively, with straws and 11 +/- 3 and 26 +/- 4%, respectively, with pellets. According to Wood et al. (1993), there are no differences between the two methods, with a motility of 66.2% and a percentage of normal acrosomes of 28.6% for the pellet method and a motility of 67.0% and a percentage of normal acrosomes of 27.4% for the straw container. However, these two authors used two different freezing protocols. A high concentration of glycerol (i.e. 8%, vol/vol) damages cat semen (Zambelli 1994; Nelson et al. 1999), because of his toxicity to spermatozoa (Graham 1996); while a concentration of 4% is suggested (Zambelli 1994). Fast green FCF Bengal pink staining is often used to evaluate the acrosomal morphology (Wood et al. 1993; Zambelli et al. 1993). As there are no studies on the influence of freezing rate on motility and on acrosomal morphology, the aim of this study was to test five freezing rates in order to verify which is the best for the cryopreservation of cat semen in straws.
Reproduction in Domestic Animals 11/2002; 37(5):310-3. · 1.36 Impact Factor
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ABSTRACT: We ultrasonographically evaluated the prenatal development in cats, from the early phases to Day 30 of pregnancy, subjecting a group of pregnant cats (n = 12) to a daily ultrasonographic exam. The ultrasonographic images allowed us to measure the minor diameter of the gestational sac and the crown-rump length of the embryo/fetus. Ten subjects underwent ovariohysterectomy at specific intervals during the pregnancy, with the aim of comparing the ultrasonographic data with real data; only two subjects brought their pregnancy to term. The earliest ultrasonographic observation of the gestational sac was on Day 10 after mating, while the embryo could be measured only beginning with Day 18. This study allowed to gather useful new data in order to clinically monitor the normal course of pregnancy in cats and to date the gestational age.
Theriogenology 06/2002; 57(8):1981-7. · 1.96 Impact Factor
