The Study on Suitable Ratios of Mixed Bedding Materials (Aspen Shavings and Corn cob) for 7-Day Cage Replacement in Mlac:DH Colony of National Laboratory Animal Center, Mahidol University

Abstract

The purpose of this study was to study the ratio of using two types of bedding materials, namely aspen shavings and corncob. Group 1 aspen shavings were more than corncob (2:1), Group 2 aspen shavings were equal to corncob (1:1), and Group 3 aspen shavings were less than corncob (1:2). The Mlac:DH guinea pig breeders were kept on mixed bedding for each group for 7 consecutive days to simulate the 7-day cage replacement period. Feed consumption, water consumption, and waste weight were collected every day. Pictures of the bedding and cleanliness of the animals' bellies were collected on days 4 and 7. Carbon dioxide (CO₂) and ammonia (NH₃) gases were measured within the animal cages daily from day 4 to day 7. It was found that the condition of all groups on the 7^th day showed no difference in the accumulated waste. The cleanliness of the animal was determined by fecal smears under the belly or the appearance of clumped hair. It was found that all three groups (both males and females) had no feces on the abdominal hair and no clumped hair after 4 and 7 days. All three groups did not differ from each other. The daily food consumption and the amount of waste in each group were not statistically different. Each group's CO₂ and NH₃ levels were within the acceptable range and were not significantly different. The water consumption of all groups was higher than the average normal water consumption of young adult guinea pigs, and the water consumption of Group 3 was significantly different from Group 1and Group 2. However, this excessive water consumption could be due to the water-play behavior of guinea pigs. For the condition of the surface of the rearing cage at the 7-day rearing, Group 1 had a higher ratio of aspen shavings than corncob, and there was more wetness accumulation than in Groups 2 and 3 because it had less adsorbent. Group 3, which has the highest corncob ratio, was the group that could absorb the most moisture. However, based on the surface texture of the bedding material after the 7-day rearing period, it was found that the corncobs were pushed up to mix in the foreground more than Groups 1 and 2 which could be a factor causing foot injury. This is considered adversely beneficial to animal health and welfare. Thus, it was concluded that the bedding mixture of Group 2 (aspen shavings equal to corncobs) was more effective than the other two groups for housing Mlac:DH guinea pig bloodstocks at the 7-day cage replacement. However, further studies were needed to carried out the effect of long-term rearing on the 7-day cage replacement.