Rabbit commercial maternal lines are usually selected for litter size (LS) and paternal lines for growth rate (GR). Line OR_LS was selected by ovulation rate (OR) and LS to improve LS more efficiently. In this study, growth traits of line OR_LS were evaluated by estimating the correlated response on weaning weight (WW), slaughter weight (SW) and GR during fattening period as well as their variability (DWW, DSW and DGR, respectively). Data were analyzed using Bayesian inference methods. Heritability estimates were low for growth traits (0.09, 0.13 and 0.14 for WW, SW and GR, respectively) and negligible for growth traits variability (0.01, 0.004 and 0.01 for DWW, DSW and DGR, respectively). Moderate common litter effect ratio (c2; 0.35, 0.28 and 0.27) and low maternal effect ratio (m2; 0.11, 0.05 and 0.01) were obtained for WW, SW and GR, respectively. Both c2 and m2 were lower at slaughter than at weaning. In addition, low common litter effect and negligible maternal effect were observed for growth traits variability. Genetic correlations between LS and both growth traits and their variability were close to zero. Positive genetic correlations were observed between OR and growth traits (0.19, 0.38 and 0.36 for WW, SW and GR, respectively) as well as between OR and growth traits variability (0.35, 0.62 and 0.20 for DWW, DSW and DGR, respectively). Positive correlated responses in both periods were obtained for growth traits, WW, SW and GR (0.037, 0.156 and 0.110 kg, respectively). The correlated response found in growth traits might be due to the positive genetic correlations between OR and these traits. However, selection for OR and LS using independent culling levels did not modify the growth traits variability. Therefore, no negative consequences on growth traits can be expected in current commercial maternal lines.

Farmer profit depends on the number of slaughter rabbits. The improvement of litter size (LS) at birth by two-stage selection for ovulation rate (OR) and LS could modify survival rate from birth to slaughter. This study was aiming to estimate direct and correlated response on LS traits and peri- and postnatal survival traits in the OR_LS rabbit line selected first only for OR (first period) and then for OR and LS using independent culling levels (second period). The studied traits were OR, LS measured as number of total born, number of kits born alive (NBA) and dead (NBD), and number of kits at weaning (NW) and young rabbits at slaughter (NS). Prenatal survival (LS/OR) and survival at birth (NBA/LS), at weaning (NW/NBA) and at slaughter (NS/NW) were also studied. Data were analysed using Bayesian inference methods. Heritability for LS traits were low, 0.07 for NBA, NW and NS. Survival traits had low values of heritability 0.07, 0.03 and 0.03 for NBA/LS, NW/NBA and NS/NW, respectively. After six generations of selection by OR (first period), a small increase in NBD and a slight decrease in NBA/LS were found. However, no correlated responses on NW/NBA and NS/NW were observed. After 11 generations of two-stage selection for OR and LS (second period), correlated responses on NBA, NW and NS were 0.12, 0.12 and 0.11 kits per generation, respectively, whereas no substantial modifications on NBA/LS, NW/NBA and NS/NW were found. In conclusion, two-stage selection improves the number of young rabbits at slaughter without modifying survival from birth to slaughter.

This study comprised of 65 infertile patients with systemic lupus erythematosus (SLE). The aim was to study causes and different modalities used for the management of subfertile patients with SLE. All patients were diagnosed to have SLE according to the standard criteria of diagnosis. All patients were scheduled to expectant treatment, ovulation induction and timed intercourse, intrauterine insemination (IUI), intracytoplasmic sperm injection (ICSI). Anovulation was in 20 patients (20%), due to PCOS in 10 cases and due to other causes in three patients. A total of 28 patients (43.1%) needed laparoscopy for their work-up of infertility. Male factor for infertility was present in nine couples (16.7%). Ovulation induction and timed intercourse was adopted for a maximum 6 cycles and IUI for 3 cycles. In vitro fertilisation (IVF)/ICSI was needed in five cases using standard long agonist protocol. Four cases were complicated by significant ovarian hyperstimulation syndrome after conventional ovarian stimulation and cycles were cancelled. Pregnancy occurred in 20 women. Ovarian stimulation for ovulation induction and IVF seems to be safe and successful in well selected women with non-complicated SLE.

Selection for ovulation rate in prolific species has not improved litter size, due to an increase in prenatal mortality, with most mortality observed in the foetal period. The aim of this study was to investigate the magnitude and timing of embryo and early foetal survival in females with high ovulation rate using hormonal treatment as a model for selection by ovulation rate. Two groups of females (treated and untreated) were used. Treated females were injected with 50 IU equine chorionic gonadotropin 48 h before mating. Females were slaughtered at 18 d of gestation. Ovulation rate (OR), number of implanted embryos (IE), number of live foetuses at 12 and 18 d (LF 12 and LF 18 , respectively) were recorded. In addition, embryo survival (ES=IE/OR), foetal survival at 18 d of gestation (FS LF18 =LF 18 /IE), foetal survival between 12 and 18 d of gestation (FS LF18/LF12 =LF 18 /LF 12 ) and prenatal survival (PS LF18 =LF 18 /OR) were estimated. For each female, the mean and variability of the weight for live foetuses (LFWm and LFWv, respectively) and their placentas (LFPWm and LFPWv, respectively) were calculated. Treated females had a higher ovulation rate (+3.02 ova) than untreated females, with a probability of 0.99. An increase in the differences (D) between treated and untreated females was observed from implantation to 18 d of gestation (D=-0.33, -0.70 and -1.28 for IE, LF 12 and LF 18 , respectively). These differences had a low accuracy and the probability that treated females would have a lower number of foetuses also increased throughout gestation (0.60, 0.70 and 0.86 for IE, LF 12 and LF 18 , respectively). According to the previous results for OR and LF 18 , treated females showed a lower survival rate from ovulation to 18 d of gestation (D=-0.12, P=0.98 for PS LF18 ). Treated females also had lower embryo and foetal survival (D=-0.10 and P=0.94 for ES and D=-0.08 and P=0.93 for FS LF18 ). Main differences in foetal survival appeared from 12 to 18 d of gestation (D=-0.09 and P=0.98 for FS LF18/LF12 ). Unexpectedly, treated females showed similar foetus weight and higher foetal placenta weight than untreated females (D=0.25 g, P=0.98) and lower variability for these traits (D=-0.02 g, P=0.72 for LFWv and D=-0.05 g, P=0.83 for LFPWv). These results are not related to a lower number of IE or LF 18 . Thus, the effect of increasing by three ova in rabbits leads to a lower embryo and early foetal survival. There seems to be no relationship between foetal mortality and foetus weight.