Scaling Relationships Between Body Weight and Fermentation Gut Capacity in Axis Deer

The axis deer (Axis axis) is a species that has garnered significant attention in recent years due to its unique characteristics and habits. In this study, we investigated the scaling relationships between body weight and fermentation gut capacity in adult male and female axis deer.

Our results show that regressions apparently had isometric scalers for fermentation gut capacity, but the relationships were not strong. This was partly because females that were pregnant had smaller fermentative gut capacities than non-reproductive or lactating animals. Interestingly, we found that forage quality, month that animal was collected, and sex did not influence scaling relationships.

We estimated the capacity of the rumen–reticulum, cecum, and colon, organs where fermentation occurs, by calculating wet weight and volume capacity. Our data showed that 8 adult male and 21 adult female axis deer were collected from January 2004 to April 2005 at a private ranch in Bastrop County, Texas.

We determined if the intraspecific scaling relationship between body weight and fermentation gut capacity was isometric for axis deer and assessed the influence of reproductive status of females on the scaling relationship. Our findings suggest that the scaling relationship between body weight and fermentation gut capacity may have implications for dietary patterns within species.

Isometric scaling relationships between body weight and fermentation gut capacity also have been suggested to explain dietary patterns within species, but whether scaling relationships are isometric within a single species is unresolved. Interspecific scaling relationships between body weight and fermentation gut capacity have a slope of 1.0 (isometric scaler) when body weights span ≥3 orders of magnitude.

In conclusion, our study highlights the importance of considering reproductive status in scaling relationships between body weight and fermentation gut capacity in axis deer. The scaling relationship between body weight and fermentation gut capacity presumably impacts dietary patterns of ruminants, such as the axis deer. Further research is needed to fully understand the implications of these findings for the ecology and conservation of this species.

Axis deer diamond weight