Coarse barley inclusion in pelleted diets for finishing pigs reduces gastric ulcers without limiting growth or increasing feed conversion ratio

The use of fine ground diets improve technical performance parameters like average daily weight gain (ADG) and feed conversion ratio (FCR). However, the use of fine ground diets is a risk factor for the formation of gastric ulcers in swine, which have a negative effect on animal welfare. The objective of this study is to improve animal welfare by reducing stomach ulcers without negative effects on animal performance parameters like FCR and ADG.

At a commercial finishing pig farm (Topigs 50 x Piëtrain; intact boars and gilts; n=880) finishers were allocated to either a control or the treatment group at the start of finishing at 25 kg of weight. Pigs in the control group received commercial fine ground barley and wheat based diets. Pigs in the treatment group received exactly the same diets, with the difference that 15% of the fine ground barley was replaced by coarse ground barley. Feeds were analyzed for nutrients and for particle size distribution (wet sieve analysis). Pigs were weighed at 0, 35, 70 and 105 days of finishing. The amount of feed supplied per pen was measured by a computer controlled dry feed installation and FCR was measured per two adjacent pens (n= 20 per treatment). To assess the effect on gastric ulcers, one batch of pigs was evaluated at slaughter using a 0-7 scoring system of the pars oesophagus building up from a smooth epithelium (0) towards different degrees of parakeratosis (1-3), different degrees in erosions and ulcers (4-6) until stenosis (7). Statistics were done using SPSS and genstat.

In total 99 stomachs (47 control, 52 treatment) were scored and photographed. Stomachs of the trial group had a significant (P< 0.001, Mann Whitney U) lower severity of stomach ulcers with an average score of 2.64 compared to the control group with a average score of 4.14. Odds ratio for a stomach score < 4 was 0.07 (p< 0.005) for the trial group. Technical performance did not differ between the control and treatment group (FCR 2.47 vs 2.49 p=0.49; ADG 869 vs 867 gram/day p= 0.85).

Partial replacement of fine ground by coarse ground barley in pelleted diets decreases the amount of stomach ulcers. This is a sustainable way to improve animal welfare of finishing pigs without increasing the use of raw materials resulting in an equal carbon footprint and economical performance.

Disclosure of Interest: None Declared.