Interrelationship between gut morphology and faeces consistency in newly weaned piglets

A total of 104 weanling piglets was used to study the interrelationships between faeces consistency and mucosal integrity, as assessed by specific aminopeptidase and isomaltase-sucrase activity, villus height and crypt depth. Piglets were weaned at 26 (s.d. 1.4) days of age, weighing 84 (s.d. 0.70) kg. On the day of weaning (day 0), dissection was performed on one group of eight piglets. The remaining piglets were given restricted amounts of diets containing different protein sources. However, during the first 7 days post weaning 72% of the piglets ate on average less than 0.9 of the amount offered and thus actually had ad libitum access to food. On days 3 or 7 post weaning pigs were weighed and euthanased. Diet composition did not effect small intestine integrity and the data were pooled for further analysis. The weight of the stomach, large intestine and pancreas increased with time post weaning (P <0.001). Small intestine weight decreased from day 0 to 3 and was increased again on day 7, exceeding the pre-weaning value (P <0.001). Isomaltase-sucrase and aminopeptidase activities were decreased on days 3 and 7 when compared with day 0. Villus height was decreased after weaning, followed by an increase on day 7 post weaning at the proximal small intestine, but by a further decrease at the mid small intestine (P <0.001). Crypt depth was increased after weaning (P <0.001). Faeces consistency was scored twice a day on a scale from 0 to 3 with increasing liquid nature. The average percentage of days during which piglets had more-liquid faeces was 26%. During the 1st week post weaning, 73% of the piglets showed a faeces score of 2 during at least 1 day. Villus height was positively correlated with food intake level, brush-border enzyme activity and dry matter content of the chyme. Villus height was negatively correlated with more-liquid faeces. Crypt depth was positively associated with the weight of various parts of the gastro-intestinal tract. It is concluded that this study supports the concept that food intake by weaned piglets determines villus height in the small intestine and brush-border enzyme production which in turn determine the risk of diarrhoea developmen