Effect of Dietary Energy Level on Milk Production in New Zealand White and Californian Does

Abstract

Objective: To evaluate the milk yield of New Zealand White and California rabbit does feed high-energy diets.

Methodology: Milk production was measured in 72 New Zealand White and Californian does from kindling to 35 days. Four high-energy diets were evaluated using the same ingredients, maintaining 17% crude protein (CP) and 14% crude fiber (CF), with increasing digestible energy (DE, kcal/kg) achieved by adding soybean oil. Milk yield was estimated under a controlled-suckling scheme across six consecutive 7-day periods. A 2×4 factorial arrangement (breed × diet) was implemented in a completely randomized design. Data were analyzed using the MIXED procedure in SAS (v. 9.4). Wood’s lactation model was fitted to characterize milk-production dynamics, estimate the day of peak yield, and evaluate lactation persistence.

Results: No differences in milk production were observed among treatments. The lactation curve exhibited an early peak (day 17) with moderate persistence (0.5). Average feed intake was similar across treatments, with no significant differences (P > 0.05).

Limitations on study: High-energy diet effects were evaluated in purebred animals; however, it would be pertinent to consider a study that includes both direct and reciprocal crosses.

Conclusions: It is recommended to use diets containing at least 17% crude protein and 2700 kcal DE·kg⁻¹ to support good milk production in New Zealand White and California rabbit does.