Modern feeding strategies for breeding boars.

Feeding of breeding boars in artificial insemination (AI) centers is critical to maintaining and improving breeding quality and performance in agriculture. Modern feeding strategies for AI boars are aiming towards maximizing their lifetime semen dose output. Given the high growth potential of modern swine genetics, AI boars should be controlled in their daily gain to reduce stress factors for the locomotion system, final body weights, and improve their survivability but also the ease of handling boars. The feeding program should be designed in such a way that young boars (up to 7 months of age) are limited to a daily gain of 400-600 g. Mature boars should be fed towards a body condition score of '2'. Aside from energy intake, protein sources should provide 0.62% SID lysine. As far as minerals and vitamins, special attention should be given to Calcium and Phosphorus as they play a crucial role in bone mineralization. A standardized total tract digestible Calcium-Phosphorus ratio between 1.75:1 and 1.82:1 seems to be most favorable. While certain nutritional requirements are needed to enable the production of ejaculates eligible for AI, considerations should be given to the mitigation of risk factors like mycotoxins, herbicides, and pesticides. Most feed additives and supplements lack consistency in their effect across studies evaluated in this review.