Salivary oxytocin changes and effect of the season in sows kept in different farrowing systems: Farrowing crate and farrowing pen with temporary crating.

Alternative farrowing systems that have been developed in recent years could have a positive effect on the welfare of sows during farrowing and lactation. Oxytocin measurements in saliva may provide information about positive animal welfare status. The purpose of this study was to evaluate the changes in salivary oxytocin concentrations in sows during the lactation period in three different farrowing systems and in two different seasons. Crossbred Duroc sows (n = 34, average parity = 3.6 ± 1.80) were housed in conventional farrowing crates (FC) (n = 10) or in farrowing pens with temporary crating (TC), including SWAP (n = 12) and JFL15 (n = 12) in two different seasons: summer and winter. Saliva samples were collected for six days during lactation: days 2, 4, 12, 23, 25 (i.e., 1-day post-weaning) and 26 (i.e., 2-day post-weaning) after farrowing. Moreover, behavioral data from sows was recorded on days 2, 4, 12 and 23 after farrowing, using a 30-s scan sampling method for 3 min per pen to record the behaviors which were assessed by the same observer. The results showed that the salivary oxytocin concentrations were 472.5 pg/mL and 399.4 pg/mL higher in both TC (SWAP and JLF15, respectively) than in the FC in early-lactation period, and these differences were more pronounced in summer and at the end of lactation in winter. In terms of behavior, higher number of mother-young interactions were observed in TC than FC in early- and mid-lactation period. In conclusion, TC is associated to a higher salivary oxytocin concentration that could indicated an increased mother-young interaction, although oxytocin concentration can be influenced by other factors, such as season or day of lactation.

Welfare and Performance of Post-Weaning Sows and Piglets Previously Housed in Farrowing Pens with Temporary Crating on a Spanish Commercial Farm: A Pilot Study.

The study investigated the effect of farrowing environment on the weaning adaptability of sows and piglets. One farrowing crate (FC) and two farrowing pens with temporary crating (TC: SWAP and JLF15) were compared. Sixty-four sows and 663 piglets were followed until 5 days post-weaning. At weaning (D24), sows and piglets were moved to group pens and nursery pens, respectively. Sows and piglets' behaviors were observed on D24, D25, and D26. On D23, D25, and D26, piglets' skin lesions were counted, and sows and piglets' saliva samples were collected for stress biomarkers (cortisol and chromogranin A, CgA). Piglets were weighed on D23 and D29. All the piglets' skin lesions increased on D25 and decreased on D26 (p < 0.05). Compared to D23, cortisol of JLF15 and CgA of FC piglets increased, whereas those of SWAP piglets remained similar after weaning (p < 0.05). Post-weaning performance in piglets was similar across farrowing systems. SWAP sows vocalized more than FC and JLF15 on D24 and D25 (p < 0.001). Results suggested that SWAP piglets showed a lower weaning stress response. Frequent post-weaning vocalization in SWAP sows might be linked with a negative effect of the abrupt separation from the piglets.

The Stomach Capacity is Reduced in Intrauterine Growth Restricted Piglets Compared to Normal Piglets.

Selection for increased litter sizes have decreased the average birth weight of piglets and up to 30% of newborn piglets in Danish herds show signs of intrauterine growth restriction (IUGR). It has been reported that around 48% of liveborn piglets dying between birth and weaning have empty stomachs, and that IUGR piglets do not ingest the recommended amount of colostrum to survive. The aim of this study was to investigate how much colostrum could be administrated depending on whether they were IUGR compared to normal piglets. Seventy-two piglets within 24 h of farrowing were classified as either IUGR or normal based on their head morphology. Stomach weight, length and capacity were measured along with bodyweight (BW). The results displayed a decreased BW, empty stomach weight and capacity in IUGR piglets, as well as a decreased relative stomach capacity in IUGR compared with normal piglets. In conclusion, birth weight is not the only factor influencing stomach capacity, and IUGR piglets have a smaller stomach capacity compared with normal piglets. It is estimated that IUGR piglets have the capacity to be given a bolus of 25 mL per kg/BW, whereas a normal piglet have a higher capacity (30 mL per kg/BW).