Abstract
Simple SummaryAt the beginning of the productive life of rabbit does, there must be a balance between ensuring at least a minimal degree of bodily development to guarantee a successful reproductive life, and the minimization of the unproductive rearing period, but nowadays there is no clear recommendation about the optimal moment for the first artificial insemination (AI). A better body condition at the first AI (higher body protein, fat and energy), that indicates a higher degree of maturity of the rabbit doe, did not influence fertility at the first AI (that is usually very high), but improved it at the second AI (that is usually lower than the first one). The percentage of kits born alive at the first and at the second AI also were positively influenced by the body protein content at the first AI. We can conclude that the degree of maturity at the first AI is a key point to optimize the does reproductive success, with body fat and body protein content being relevant factors.The relationship among live weight, chemical body composition and energy content (at artificial insemination (AI) and three days before parturition), estimated by bioelectrical impedance with fertility rates and the percentage of kits born alive, was studied during the first three AI. The first AI was conducted at 16 weeks of age in 137 rabbit does that weighted 3.91 ± 0.46 kg. Their body chemical composition was 17.4 ± 0.50%, 16.1 ± 2.6%, 1067 ± 219 kJ/100 g body weight, for protein, fat and energy, respectively. An increase in body protein, fat and energy content at the first AI did not affect fertility at the first AI but improved it at the second AI (p ≤ 0.030). Moreover, an increase in body fat and energy content at the second AI improved fertility at the second AI (p ≤ 0.001). Fertility at the third AI was positively influenced by body protein at the third AI and the increase in body protein and fat between the second parturition and the third AI (p ≤ 0.030). The percentage of kits born alive at the first and at the second AI improved with the increase in body protein at the first AI (p ≤ 0.040). In conclusion, a minimal body protein and fat content is required at the first AI to optimize the reproductive performance in young does.
Highlights
Introduction distributed under the terms andIn the last four decades, rabbit production underwent a noticeable change from a traditional and familiar organization to industrial and intensive systems
Data of the estimated body chemical composition, the fertility and percentage of kits born alive recorded in two different farms in 2010 were used in order to obtain a wide variation in chemical body composition
The initial live weight and chemical composition of rabbit does had a wide range of variation, which was more important for the fat than for the protein content (16 vs. 3%, respectively, for coefficient of variation (Table 2))
Summary
Introduction distributed under the terms andIn the last four decades, rabbit production underwent a noticeable change from a traditional and familiar organization to industrial and intensive systems. Genetic selection programs and new breeding management systems were established, improving the production of the new hybrid lines used. This has led to an increase in conditions of the Creative Commons. There is an optimal threshold for birth weight (>57 g) to optimize the initial reproductive performance, which is associated with an increase in the live weight and fat reserves at the first AI [12,13,14] The latter are the traits used to define the maturity of rabbit does at the first AI, and both are related to the nutritional rearing strategy and the time of AI [13,15]. The final aim is to extend the lifespan of rabbit does, which is limited by the relatively high early mortality and culling rate in intensive production systems [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
