The use of nurse sows in Danish piggeries is common practice because of large litter sizes; however, the effect of being selected as a nurse sow on subsequent reproductive performance is unknown. Therefore, the aim of this study was to quantify a nurse sow's reproductive performance in the subsequent litter. Nurse sows were defined as sows weaning their own litter at least 18 days postpartum and thereafter nursing another litter (nurse litter) before service. Data (2012-2013) from 20 piggeries with more than 14.5 live born piglets per litter and a stable distribution of sows among parities over time were selected. Records from 79,864 litters were obtained and analyzed using mixed linear and logistic regression models. The average lactation lengths were 40.3 days for nurse sows and 27.8 days for non-nurse (normal) sows. Nurse sows weaned on average 12.4 piglets and subsequently 11.5 nurse piglets, whereas non-nurse weaned 11.7 piglets in their single weaning. There was no difference in re-service rate between nurse and non-nurse sows in the subsequent reproductive cycle. Subsequent litter size in the next reproductive cycle was higher for nurse sows than that for non-nurse sows (18.69 vs. 18.11 total born piglets; P
Social anxiety is a common problem in psychotic disorders. The Liebowitz Social Anxiety Scale, Self-Rating version (LSAS-SR) is a widely used instrument to capture different aspects of social anxiety, but its psychometric properties have not been tested in this patient group. The aims of the present study were to evaluate the psychometric properties of the LSAS-SR in patients with first episode psychosis, to investigate whether it differentiated between active and passive social withdrawal and to test which clinical factors contributed to current level of social anxiety.
A total of 144 first episode psychosis patients from the ongoing Thematically Organized Psychosis (TOP) study were included at the time of first treatment. Diagnoses were set according to the Structured Clinical Interview (SCID-1) for DSM-IV. A factor analysis was carried out and the relationship of social anxiety to psychotic and general symptomatology measured by the Positive and Negative Syndrome Scale (PANSS) was evaluated. Possible contributors to social anxiety were analyzed using multiple hierarchic regression analysis.
The factor analysis identified three subscales: public performance, social interaction and observation. All three subscales showed satisfactory psychometric properties, acceptable convergent and discriminate properties, and confirmed previous findings in social anxiety samples. Self-esteem explained a significant amount of the variance in social anxiety, even after adjusting for the effects of delusions, suspiciousness and depression.
The study shows that the LSAS-SR can be used in this patient group, that social anxiety is strongly related to both behavioral social avoidance and to self-esteem. The results support the use of this measure in assessment of social anxiety in both clinical settings and in research.
Straw possesses many characteristics that make it attractive to pigs and can therefore be effective in preventing negative penmate-directed behaviours. However, straw is difficult to handle in current vacuum slurry systems under most commercial conditions and can therefore only be used in limited amounts. To occupy pigs effectively, straw must remain attractive to pigs throughout the whole day; hence, have a certain degree of novelty. We investigated the penmate-directed behaviour of liquid-fed growing pigs in a production herd, assigned to five experimental treatments: 1×25, 1×50, 1×100, 2×50 and 4×25 g of chopped straw/pig per day, with 20 replicates of each treatment (pen was regarded as experimental unit). Behaviour was observed at two different growth stages; ~40 and 80 kg live weight of the pigs. Activity and exploratory behaviour directed at penmates, straw, pen components and the slatted floor were registered continuously for 15 min of each hour during day time (0600 to 2200 h) by use of video observation of three focal pigs per pen. The pigs were active for about one-third of the day corresponding to ~5 h/day. Of the active time, an average of 7% (35 min) was spent on penmate-directed behaviour. The pigs were more active and increased their straw-directed behaviour when provided with 100 g straw/pig per day compared with 25 and 50 g (P0.05), and there was no effect on pigs' behaviour when straw provision was increased per day (P>0.05). Pigs became less active and reduced their straw-directed activities when their weight increased from 40 to 80 kg live weight (P0.05). Further, the residual straw results indicated that perhaps a more frequent straw provision could help establish a more even level of fresh available straw during the day. However, the frequent straw provision did not occupy pigs more than one daily allocation did. In conclusion, there was no difference in penmate-directed behaviour of the pigs when given 25 or 50 g of straw/pig per day compared with 100 g of straw/pig per day, nor were there any difference when 100 g of straw/pig per day was provided more frequently.