# Effect of Dietary Protein Levels on Performance and Health Status of Adult Companion Rabbits

## TL;DR

This study shows that adult rabbits need different protein diets based on their sex to maintain good health and avoid nutrient imbalances.

## Contribution

The study identifies sex-specific dietary protein needs in adult rabbits to optimize health and feed efficiency.

## Key findings

- A low-protein diet (165 g/kg) was sufficient for adult rabbits' health and maintenance.
- Males and females have different nutritional needs, with males requiring more protein and energy.
- Feeding diets tailored by sex can improve feed efficiency and overall well-being in rabbits.

## Abstract

Feeding adult companion rabbits with diets supplying adequate protein levels may help maintain good health without overloading them with nutrients they do not need. In this study, 117 adult companion rabbits were fed balanced diets, differing only for their crude protein content. Results showed that the lowest protein diet tested was enough to support health, body maintenance, and energy and nutrient digestibility, while the higher protein diets caused an excess of digestible protein relative to available energy. Results highlight that male and female rabbits have different nutritional needs at adult stage. Feeding both sexes the same diet may lead to energy and nutrients imbalances in one or both sexes. Tailoring diets based on sex can improve feed efficiency, body condition, and overall well-being in companion rabbits. These findings offer practical advice for pet owners, veterinarians, and feed producers to improve rabbit care through better, more targeted feeding strategies.

Three isoenergy diets with different crude protein (CP) levels (H = 175, M = 173, and L = 165 g/kg, as is), were fed to 117 sex balanced rabbits (coloured dwarf breed) from 28 to 45 weeks of age. Feed intake, body weight, and fatness were unaffected by the dietary treatment. By reducing dietary CP content, rabbits in group L had a significantly reduced proportion of digestible protein (DP) relative to maintenance requirements compared to group H; p < 0.001), but still exceeding their DP needs. The initial body weight of females was significantly greater than that of males, a difference maintained throughout the study period. Males consumed more feed than females (86.0 vs. 75.2 g/d, p < 0.001) and at 45th week, the skin fold width of males was higher than that of females (p < 0.001). DP balance remained positive in both sexes but was higher in males than females (+3.37 vs. +2.50 g DP/d; p < 0.001). Contrarily, the energy balance was positive in males (+57.9 kJ DE/d) and negative in females (−20.3 kJ DE/d). In conclusion, a dietary CP level of 165 g/kg is considered adequate for adult companion rabbits at maintenance. It is therefore advisable to diversify diets by sex to better meet their nutritional requirements.