Optimización genética y nutricional para la producción de cerdo ibérico cruzado tradicional

Abstract

Animal production these days faces great challenges due to high production costs and an increasingly demanding market. The market demands higher quality products, obtained under farming conditions that guarantee animal welfare and environmental conservation. The work carried out in this Doctoral Thesis is focused on investigate and development, in field conditions, genetic selection and nutritional adjustment mathematical models. Based on the scientific advances of the last decades for the economic optimisation of livestock production, and adapted to the traditional production of Iberian pigs. A meat production of high gastronomic value, carried out in a sustainable way in an environment of high ecological value such as the spanish dehesa. Regarding with genetic selection, the productive performances of the Iberian pig are far from those of commercial breeds. The genetic selection model developed in experiment 1 was used to adapt genetically the Iberian and duroc TemplarioTM populations to the optimal production objectives of a traditional iberian pig (50% duroc) raised outdoor. By implementing protocols for collecting data on traits of interest, designing a selection index, controlling inbreeding and evaluating the phenotypic improvement of traits: intramuscular fat, lean, leg cane perimeter, reproductives, and external homogeneity. Durong the study, a trend of improvement in intramuscular fat expression was observed, thanks to the selection of the best breeders by their selection index. As for the sow nutritional models: • In experiment 2.1, the growth and feeding pattern of the Iberian gilt were studied, which was used: a) to design an economically optimal feeding programme for its correct reproductive and functional development; and b) as a reference for the adjustment of the patterns in gestation and lactation cycle by cycle. • In experiment 2.2, the patterns of physiological changes and feeding of sows in gestation and lactation were studied on a cycle-by-cycle basis to: a) optimise lactation weight losses; b) optimise weaned litter weight; and c) an economically optimal feeding programme. It was observed that the sow is most efficient between cycles 3 and 5, producing the cheapest kilogram of weaned piglet in her entire productive life, at an average of 1,6 euros per cycle (gestation + lactation). It should also be noted that the optimal average feed conversion rate, translated in kilograms of litter produced by the sow per cycle (gestation + lactation), of the 7 cycles of the study, was 8,85 kg, with a cost of 1,80 €. Finally, experiment 3 studied the growth and feeding patterns, and the effect of sex, terminal boar, and content of antioxidant additives in the finishing feed, on the performance, carcass and meat quality parameters, of the progeny born in genetic control developed in this thesis, of two consecutive generations of TemplarioTM duroc boars, crossed with the iberian TemplarioTM sow of the foundational population, reared in outdoor conditions. The growth and feeding pattern obtained provided the knowledge for the design of an economically optimal feeding program to produce the cheapest kilogramme of meat. Obtaining a feeding cost of 169.08 €/animal. Significant differences (p<0.05) were found for effect of the genetic improvement of the terminal boar and sex on the % intramuscular fat, fat cover and loin depth. Without significantly affecting (p<0.05) the performance or carcass quality. And also, it was demonstrated that including vitamin E in the finishing feed combined in sinergy with other natural antioxidants (INGASO QTMEAT®) showed a significative positive effect (p<0,05) on carcass lipid oxidation, with special interest in the protection of omega 3 fatty acids, with beneficial properties for human health, with aim of producing meat as functional food.