High fiber diet reduces stereotypic behavior of gilts but does not affect offspring performance

Indicators of improved gestation housing of sows. Part I: Effects on behaviour, skin lesions, locomotion, and tear staining

Commercial gestation housing systems for sows generally fail to cater fully for their needs in terms of comfort or the ability to perform highly motivated behaviours, which can lead to chronic stress and an impairment to welfare. We compared a typical gestation system (CONTROL) with an IMPROVED one as regards oral stereotypies, aggressive behaviour, skin lesions, locomotion, and tear staining. Sows were mixed into 12 stable groups (six groups per treatment, 20 sows per group), 29 days post-service in pens with free-access, full-length individual feeding/lying stalls. CONTROL pens had fully slatted concrete floors, with two blocks of wood and two chains suspended in the group area. IMPROVED pens were the same but with rubber mats and a length of manila rope in each feeding stall, and straw provided in three racks in the group area. Direct observations of oral stereotypical (30 instantaneous scans per sow per day) and aggressive (all-occurrence sampling, 3 h per sow per day) behaviours were conducted 72 h post-mixing, in mid and late gestation. Skin lesions were counted 24 h and three weeks post-mixing, and in late gestation. Sows' locomotion (locomotory ability) was scored using a visual analogue scale in mid and late gestation. Right and left eye tear staining was scored in late gestation. Indications of better welfare in IMPROVED sows included performance of fewer oral stereotypies in mid and late gestation, and lower tear stain scores. These sows performed more aggression in late gestation, which was associated with access to enrichment, but skin lesion counts were not affected. Thus, the changes made in the IMPROVED treatment benefitted aspects of sow welfare.

The Role of Dietary Fiber in Improving Pig Welfare

This review aims to discuss the effects of dietary fiber sources with various levels on stereotypic behaviors in sows. There are a variety of dietary fiber sources that are supplemented to feeds for sows. However, dietary fiber sources have different physio-chemical properties, leading to controversial results in feed motivation, nutrient digestibility, and behaviors in sows fed fiber-rich diets. Findings from previous studies indicated that soluble fiber delays nutrient absorption and decreases physical activity after feeding. In addition to this, it increases volatile fatty acid production, provides energy, and prolongs the feeling of satiety. It also prevents certain stereotypies and thus is paramount to sow welfare.

Effects of Dietary Fiber on Growth Performance, Nutrient Digestibility and Intestinal Health in Different Pig Breeds

To explore the effect of dietary fiber on growth performance and intestinal health in different pig breeds, forty Taoyuan and Duroc pigs (pure breeds) of 60 days of age were randomly divided into a 2 (diet) × 2 (breed) factorial experiment (n = 10), and fed with a basal diet (BD) or high-fiber diet (HFD). The trial lasted for 28 d, and results showed that the Taoyuan pigs had a higher average daily feed intake (ADFI) than the Duroc pigs (p < 0.05). The average daily gain (ADG) and digestibilities of gross energy (GE) and crude protein (CP) were higher in Taoyuan pigs than in the Duroc pigs under HFD feeding (p < 0.05). The HFD increased the superoxide dismutase (SOD) and catalase (CAT) activity in Taoyuan pigs (p < 0.05). Interestingly, Taoyuan pigs had a higher jejunal villus height and ratio of villus height to crypt depth (V/C) than the Duroc pigs. The HFD significantly improved the villus height and V/C ratio in duodenum and jejunum (p < 0.05). The HFD also increased the jejunal maltase and ileal sucrase activities in Duroc and Taoyuan pigs, respectively (p < 0.05). Taoyuan pigs had a higher expression level of duodenal fatty acid transport protein-1 (FATP-1) than the Duroc pigs (p < 0.05). Furthermore, the HFD acutely improved the expression levels of ileal SGLT-1 and GLUT-2, and the expression levels of jejunal occludin and claudin-1 in Taoyuan pigs (p < 0.05). Importantly, Taoyuan pigs had a higher colonic Bifidobacterium abundance than the Duroc pigs (p < 0.05). The HFD not only elevated the colonic Lactobacillus abundance and butyrate acid content in Taoyuan pigs, but also increased the acetic and propionic acid contents in both the pig breeds (p < 0.05). These results indicated a difference in dietary fiber (DF) utilization by the two pig breeds, and results may also suggest a beneficial character of DF in regulating intestinal health.

Metabolic Responses of Dietary Fiber during Heat Stress: Effects on Reproductive Performance and Stress Level of Gestating Sows

Heat stress is an important issue, and the addition of fiber to the diet is an option in modifying intestinal health. This study evaluated the effect of acid detergent fiber (ADF) levels on reproductive performance, intestinal integrity, and metabolism of gestating sows, and its carry-over effect on the lactation period during heat stress. The diets included 4.3% (Low fiber; LF), 5.4% (Medium fiber; MF), and 6.5% (High fiber; HF) ADF. Sows fed the HF diet showed a lower respiratory rate, hair cortisol concentration, and farrowing duration compared with the LF treatment. The HF diet increased the pyruvate, citrate cycle, glyoxylate, dicarboxylate, and thiamine metabolism compared with the MF. The concentration of acetate and total short-chain fatty acids were increased in the sows fed the HF diet. The gene expression of glucose transporter 3 and glucose transporter 4 was increased in the HF treatment. The gene expression of heat shock protein 70 was decreased in the HF treatment. The HF diet during gestation increased feed intake, constipation index, piglet weight, and litter weight compared with the LF. Sows in the LF treatment showed the greatest digestibility of crude protein and the lowest digestibility of ADF. In conclusion, a 6.5% ADF level is recommended for gestating sows during heat stress.