Location: Livestock Behavior Research2011 Annual Report
1a. Objectives (from AD-416)
The overall objective of our current work program is to identify husbandry and environmental factors that challenge animal well-being and develop sustainable alternatives that safeguard well-being and productivity. The specific objective of this project is to determine the effects of different dietary ingredients on the incidence and severity of gastric ulcers in sows and their impact on sow longevity.
1b. Approach (from AD-416)
Diet is thought to have a significant influence on the development of ulcers in swine. Our study will investigate the effects of a proton pump inhibitor (e.g. Nexium), sodium bicarbonate and dietary roughage on stomach lesions and abnormal oral behavior in breeding sows. Sows and gilts will be housed individually in stalls with each animal as an experimental unit. Newly-bred sows and gilts will undergo initial evaluation to assess the extent of gastric ulceration already present using endoscopy. Gastric ulceration in the esophageal region will be scored on 7-point scale (Mackin et al., 1997 – see below). Score Endoscopic appearance Grade 0 No visible lesions A 1 Shallow erosions < 10% of pars esophagea 2 Shallow erosions 10-20% of pars esophagea B 3 Shallow erosions > 20% of pars esophagea 4 Deep ulcerations < 10% of pars esophagea 5 Deep ulcerations 10-20% of pars esophagea 6 Deep ulcerations >20% of pars esophagea C Following initial assessment, 12 sows and gilts will be assigned to one of four treatment groups so that parity and current ulcer levels are balanced across treatments. Treatments will be: 1) Control – C – commercial gestating sow diet fed once per day. 2) Proton pump inhibitor – N – commercial gestating sow diet fed once per day plus single daily dose of 60 mg esomeprazole magnesium throughout gestation. 3) Sodium bicarbonate – S – commercial gestating sow diet once per day with sodium bicarbonate included at 2% throughout gestation. 4) Roughage – R – high fiber diet with lower metabolizable energy and fed twice per day. For all animals, the effects of treatments will be investigated every 4 weeks over the gestation period to determine whether treatments have positive, neutral or negative effects on ulceration. This investigation will include endoscopy, behavioral analysis and heart rate responses to feeding, using Polar S810 heart rate monitors. The behavior data collected will include 24h time-lapse video data and 4h real-time video data recorded over feeding collected in conjunction with heart rate data. Twenty-four-hour behavioral data will be analyzed to determine time budgets. Real-time behavioral data will be analyzed to determine types and durations of oral behaviors, such as bar-biting, sham-chewing and drinker-pressing, both pre- and post-feeding and compared both within and between treatments. Heart rate data will be downloaded and analyzed to determine mean heart rate associated with oral behaviors and heart rate responses to feeding. Again, these will be compared both within and between treatments. Weights and backfat measures will be recorded at monthly intervals and productivity and feed intakes at farrowing and over lactation will be recorded. Animals will stay on the experiment through lactation. Stomach morphology data will also be collected on any sows culled before the end of the trial.
3. Progress Report
Diet and stress are thought to have a significant influence on the development of stereotypic behavior and of ulceration of the pars esophagea region of the stomach in swine. Our study aimed to determine the effects of diet ingredients on ulcers, salivary pH and oral behavior in breeding sows. We completed the analysis of our ulcer score and production data, and the extraction and final analysis of the behavioral and heart rate data is ongoing. Our experiment involved 48 sows randomly assigned to 1 of 4 treatment groups. Treatments were: 1) control, a commercial gestating sow diet; 2) proton pump inhibitor, a commercial gestating sow diet plus a single daily dose of 60 mg omeprazole; 3) sodium bicarbonate, a commercial gestating sow diet with sodium bicarbonate included at 2% of the diet; 4) roughage, a high fiber diet (25% soybean hulls) fed at a higher feed intake to equal the energy of the control diet. Treatments were initialized at day 30 and all diets were fed once per day. All sows underwent initial endoscopic evaluation at day 30 of gestation to assess ulcers already present using a 7-point scale and initial salivary pH was measured. Behavior was recorded to determine frequencies and durations of stereotypies. Ulcers were investigated at day 60 and day 90 of gestation. We found that dietary treatment had no effect on ulcer scores or on production measures such as litter size, piglet weight, or lactation feed intake. Salivary pH did not correlate with ulcers and there was no treatment effect, but there was a change in salivary pH throughout the day with the highest pH (8.99 ± 0.05) at 7 a.m. and lowest pH (8.88 ± 0.02) at 1 p.m. While treatment had no effect on behavior, there was an effect of day 60 ulcers on bar-biting and drinking with bar-biting and drinking increasing as ulcers worsen. The results indicate that the selected treatments did not influence ulcers. However, further analysis of the behavior data is needed to elucidate any effects on behavior. Over the past year, project progress was monitored during weekly meetings with graduate research staff and bimonthly meetings with Co-Primary Investigators.