QLIF project 1: Interactive effects of pig genotype and amino acid balance in the diet

A feeding trial is carried out to test the hypothesis that pigs with different genetic potential for lean growth react differently on an unbalanced supply with amino acids in the grower and the subsequent finisher phase, and thereby provide different sensorial quality of pork. 

The effect of genotype, feeding regime, and their interactions were assessed with regard to parameters of performance, carcass and pork quality. The reduced supply with essential amino acids in the experimental treatments represent the limited availability of these nutrients in organic pig production.

The experiment was previously designed as follows:

• Control treatment: using a hybrid genotype and the diet closely related to the requirements of the pigs as  an internal standard and control treatment.
• Treatment A: a selected line for high lean growth fed with a diet unbalanced in AA in the grower and finisher phase which has been validated to increase intramuscular fat content and sensorial quality.
• Treatment B:  an indigenous breed fed with a diet unbalanced in AA in the grower and finisher phase.
• Treatment C: a selected line for high lean growth fed with a AA-balanced diet in the grower and AA- unbalanced diet in finisher phase.
• Treatment D: an indigenous breed fed with an AA-unbalanced diet in the grower and AA-unbalanced diet in the grower and the AA-unbalanced diet in the finisher phase.

The selected genotypes were: (i) Pietrain x Westhybrid (Pi x Westhy), (ii) a cross bred with Duroc (Du x F1), (iii) German Saddle back x Pietrain (SH x Pi) and (iiii) pure German Saddle back breed (SH). The first two breeds had 22 animals per feeding regime (11 male and 11 female). The genotypes iii and iiii included only males (11 each group). The feedstuffs were organically produced and formulated to three feeding regimes: the first (I) attending the recommendations of the German Society of Nutritional Physiology (GfE, 1987); the second (II) with a reduced supply of essential amino acids in the finisher phase and the third (III) with a reduced supply of essential amino acids in both the grower and the finisher phase. The animals were housed individually in pens and slaughtered at a live-weight of 120 kg.

1. Performance criteria: composition of the diets, feed intake, daily gain, feed conversion ratio, carcass characteristics: lean cut yield, subcutaneous fat, M. longissimus (area, color, score, firmness score) (n = 198).
2. Quality criteria: pH1, pH24, conductivity, reflection, IMF content (% in M.l.d.), fatty acids, shear force, drip loss (%).
3. Histological criteria: total number of muscle fibers.
4. Sensorial quality (hedonic test by CTSCCV): tenderness, juiciness, flavor, overall estimation.

Dr. Yunior Aragon

• organic
• pork
• genotype feeding interaction

03/04- 09/05

 EU Commission (Project CT - 2003 506358)

• Haus Düsse Agricultural Center, ;NRW in Sassendorf
• CTSCCV, Maison Alfort, France