ABSTRACT We evaluated the maternal behavior, physiology, and reproductive performance of both Damin (Min-pig × Large White) and Large White gilts to identify the advantages hybrid sows offer with regard to stress relieve and improvement of the welfare level of sows during late lactation. First-parity Damin gilts (n = 40) and first-parity Large White gilts (n = 40) were farrowed in individual pens. Video surveillance was used to monitor the occurrence of lateral recumbency and compare it to other postures, such as ventral recumbency, defecation, urination, tail posture, sham-chewing, and bar-biting behaviors. Monitoring was conducted from 07:00 to 09:00 h and from 13:00 to 15:00 h on days 3 and 6 of each week from the third to the fifth week post-parturition. In addition, the concentrations of tumor necrosis factor-α, interleukin-6, and salivary α-amylase were assessed. During the fourth week postpartum, Damin gilts showed a higher frequency of postural changes from lateral recumbency to other postures and less ventral recumbency, sham-chewing, and bar-biting behavior compared with Large White gilts. However, no significant differences were found between Damin and Large White gilts with regard to urination, defecation, tail wagging, and “tail low” behaviors. The concentrations of serum interleukin-6, salivary α-amylase, and serum tumor necrosis factor-α were higher in Damin gilts than in Large White gilts during the fifth week postpartum. Damin gilts partly achieve lower stress levels during late lactation and better animal welfare than purebred Large White gilts.

ABSTRACT This study was performed to compare changes in posture, nursing behavior, and production performance of two breeds of sows. The posture, postural changes, nursing behavior, and production performance of hybrid Damin (Large White × Min pig, n = 32) and Landrace × Large White (n = 32) sows were observed by video recording for 72 h after farrowing and from 07:00 to 09:00 h and 13:00 to 15:00 h within any successive two-day period of each week from the two to five weeks postpartum. The production performances were compared between the two breeds. Except standing at days 1 to 3 postpartum and sitting at day 2 postpartum, there were significant differences in postures between the two breeds of sows. The frequency of ventral-to-lateral recumbency at day 1 and weeks 4 and 5 postpartum and sitting-to-lying at days 1 and 3 and weeks 4 and 5 postpartum was significantly lower for the Damin than for Landrace × Large White sows. The frequency of standing-to-lying in the first 72 h postpartum was significantly higher for the Damin than for Landrace × Large White sows. At days 2 and 3 postpartum, piglet loss was significantly lower for the Damin than for Landrace × Large White sows. The duration of parturition and farrowing interval were significantly longer for the Landrace × Large White than for Damin sows. The number of live piglets was higher for the Damin than for Landrace × Large White sows. The birth weight of litters and weaning weight of piglets were lower for Damin than for Landrace × Large White piglets. These data suggest that the Damin sows showed stronger maternal instincts through their behaviors and postural changes compared with the Landrace × Large White sows.

Microbial lipids, which are also known as single cell oils (SCO), are produced by oleaginous microorganisms including oleaginous bacteria, yeast, fungus and algae through converting carbohydrates into lipids under certain conditions. Due to its unique environment having extremely low temperature and anoxia, the Tibetan Plateau is amongst the regions with numerous rare ecotypes such as arid desert, salt marsh, alpine permafrost, hot spring, and lawn. By using a rapid, convenient screening method, we identified 31 strains of oleaginous microorganisms from different habitats in the Tibetan Plateau, which include wetlands, lawn, hot spring, alpine permafrost, and saline-alkali soil. Molecular identity analysis showed that they belong to 15 different species, 7 of which are reported for the first time as lipid-producing microorganisms, that is, Cladosporium sp., Gibberella fujikuro, Ochrobactrum sp., Plectosphaerella sp., Tilletiopsis albescens, Backusella ctenidia, and Davidiella tassiana. The distribution of the oleaginous microorganisms varies with habitats. 11 strains were found in hot spring (35.5%), 10 in farmland (32.3%), 6 in lawn (19.4%), 2 in sand (6.4%), 1 in wetland (3.2%), and 1 in permafrost (3.2%). Carbon utilization analysis indicated that most of these filamentous fungi can use xylose and carboxymethyl cellulose (CMC) as carbon source, where Backusella ctenidia, Fusarium sp. and Gibberella fujikuroi have the strongest capability.