Fertilizing ability of electro-ejaculated cryopreserved semen in the domestic cat.

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.

Effect of EGF on in vitro maturation of domestic cat oocytes.

The objective of this study was to evaluate the influence of different concentrations of epidermal growth factor (EGF) on in vitro maturation of domestic cat oocytes. A total of 444 cat oocytes were matured in MSOF (maturation synthetic oviductal fluid) in the presence of varying EGF concentrations: (1) MSOF (control); (2) MSOF+10 ng/mL EGF (EGF10); (3) MSOF+25 ng/mL EGF (EGF25); and (4) MSOF+50 ng/mL EGF (EGF50). After IVM, oocytes were in vitro fertilized to verify the effect of adding EGF on cytoplasmic maturation.

Correlation between fetal age and ultrasonographic measurements during the second half of pregnancy in domestic cats (Felis catus).

We ultrasonographically evaluated the prenatal development in cats, from Day 30 to the end of pregnancy, subjecting a group of pregnant cats (n = 8) to daily ultrasonographic examinations. The ultrasonographic images allowed us to measure the diameter of the fetal abdomen, the biparietal diameter of the fetal skull and the diameter of the fetal stomach. A correlation between these measurements and gestational age was found with a linear, parabolic and exponential regression analysis.

Vaginal and cervical anatomic modifications during the oestrus cycle in relation to transcervical catheterization in the domestic cat.

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.

Cryopreservation of cat semen in straws: comparison of five different freezing rates.

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.

Equine fetal sex determination using a single ultrasonic examination under farm conditions.

The aims of this study were to evaluate the reliability, under general farm conditions, of the use of a single transrectal sonogram in pregnant mares to determine fetal sex by locating the genital tubercle, and the feasibility of extending the period of gestation in which this examination can be carried out. This research was done during routine reproductive examinations on three different stud farms. Forty mares between the 54th and the 89th day of gestation were examined once; gestation was calculated by identifying the last day of mating as Day 0.

Correlation between the age of the conceptus and various ultrasonographic measurements during the first 30 days of pregnancy in domestic cats (Felis catus).

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.