The effect of intravaginal applied gonadotropin-releasing hormone agonist on different oestrous parameters and reproductive performance in post weaned sows.

In a Hungarian large breeding unit, 481 weaned sows were assigned to three groups and were treated as follows. Sows in Group 1 (Control, n=161) were artificially inseminated (3.01 +/- 0.4 times) during their standing reflex; sows in Group 2 (n=160) were artificially inseminated 3 times at 12-hour intervals, independent of detection of oestrus and immediately after administration of a GnRH-agonist at 96 hours postweaning; and sows in Group 3 (n=160) were artificially inseminated 3 times at 12-hour intervals, beginning at their standing reflex after administration of a GnRH-agonist. Pre-trial daily average lactational feed intake, average daily feed intake from weaning to oestrus, oestrus within 6 days of weaning (%), ovulation within 6 days of weaning (%), wean-to-oestrus interval (h), duration of oestrus (h), follicle size (mm), interval from oestrus to ovulation (h), subsequent day 24 pregnancy rate (%), farrowing rate (%) and total number of pigs born were evaluated. Pre-trial average daily voluntary lactational feed intake was 7.1 +/- 0.5 kg in Group 1, 7.2 +/- 0.4 kg in Group 2, and 7.3 +/- 0.7 kg in Group 3 (P > 0.05). Average voluntary daily feed intake from weaning-to-oestrus was 4.3 +/- 0.9 kg in Group 1, 4.2 +/- 0.8 kg in Group 2, and 4.1 +/- 0.5 kg in Group 3 (P > 0.05). Oestrus was detected within 6 days of weaning in 143 (88.8%) sows in Group 1, 143 (89.4%) sows in Group 2, and in 142 (88.8%) sows in Group 3. Follicle size did not differ (P > 0.05) among the groups. In Group 1, 83.2%, in Group 2, 90.6%, and in Group 3,91.3% of the sows ovulated within 6 days of weaning (P < 0.05), but there were no significant (P > 0.05) differences in 24 Day pregnancy rates (81.4%; 91.3%; and 92.5%). Farrowing rates were in Group 1, 84.5%, in Group 2, 91.3%, in Group 3, 91.9% (P > 0.05). Wean-to-oestrus interval was 115.5 h in Group 1, 114.9 h in Group 2, and 115.7 h in Group 3 (P > 0.05). Duration of oestrus was significantly shorter in Group 2 (41.9 h) and Group 3 (42.1 h) than in Group 1 (68.3 h) (P < 0.001). Similarly, the interval from oestrus to ovulation was significantly different (P < 0.01) between the groups (Group 1, 49.0 h Group 2, 32.0 h, and Group 3, 31.1 h). Sows in Group 2 (12.7) and Group 3 (12.6) had a significantly higher (P < 0.01) number of pigs born than sows in Group 1 (n = 10.9). The interval between oestrus and ovulation was highly and positively correlated (r = 0.83) with the duration of oestrus.

Maladaptive behavioural patterns of early weaned, indoor raised pigs.

The objective of the present study was to investigate the growth rate and maladaptive behaviour of early (day 14 of lactation) or late (day 28 of lactation) weaned pigs of either sex kept under different light intensities. Maladaptive behaviour was diagnosed when piglets were kept under a high light intensity but not when kept under a low light intensity. The time, spent engaged in maladaptive behaviour was not higher for barrows than for gilts. Lesions on 'recipient' animals were more severe in larger pigs with a greater rate of weight gain than in smaller ones. 'Perpetrator' pigs grew more slowly during the 46 days after weaning (P = 0.0013) than the non-preparator-pigs. 'Recipient' animals were significantly heavier and had higher rates of weight gain (P = 0.0003) than the 'perpetrator' pigs.

The course of acute-phase proteins and serum cortisol in mastitis metritis agalactia (MMA) of the sow and sow performance.

The objective of this study was to evaluate changes in acute-phase proteins (APPs) during mastitis metritis agalactia (MMA) in sows. Sows with MMA (group one, n=15) and healthy sows (group two, n = 15) were evaluated at days 0, 5, 10, 15, and 20 postpartum. Number of total born, liveborn, stillborn, and mummified pigs did not differ significantly between the groups. Preweaning mortality was higher (P < 0.001) among MMA sows than among healthy control animals. The offspring of healthy sows had higher (P < 0.05) weaning litter weights than the off-spring of MMA sows. Mean serum alpha 1-acid glycoprotein (AGP) concentrations were higher in MMA sows on the days 1 (P < 0.05), 5 (P = 0.05), and 10 (P < 0.001) post partum. Mean serum haptoglobin (HPT) was higher in MMA sows on days 1, 5 (P < 0.001), and 10 (P < 0.05) of lactation. Cortisol serum concentrations up to day 10 post partum were higher (P < 0.001) in MMA sows than in healthy sows. AGP was negatively correlated with litter weight, indicating that activation of the cellular immune response in sows negatively affects the growth rate of suckling piglets. Correlations were found between the overall means for weight, acute-phase proteins, and serum cortisol concentration.