Comparison of total tract digestibility and nitrogen balance between Cinta Senese and Large White pigs fed on different levels of dietary crude protein

Abstract

a b s t r a c tThe work aimed to study the digestive capacity and nitrogen balance of Cinta Senese pig fed diets with different crude protein (CP) content. Twelve castrated male pigs (6 Cinta Senese and 6 Large White), of the same body weight (on average 62.7 kg), were submitted to 8 subsequent trials of total tract digestibility and nitrogen balance. The pigs were kept in metabolism cages allowing collection of faeces samples and total urine. The diets, of exclusive vegetal origin, were formulated to contain four protein levels 70, 100, 130 and 160 g/kg as fed (named CP7, CP10, CP13 and CP16, respectively) assured mainly by soybean meal. Total tract nutrient apparent digestibility did not differ (P>0.05) between breeds. Apparent digestibility of CP increased (P<0.01) with increasing dietary CP (from 0.756 to 0.874 for Cinta Senese and from 0.742 to 0.868 for Large White), as consequence of faecal endogenous nitrogen which underestimates the digestibility of protein in inverse proportion with its amount in the diet. Nitrogen balance showed that breed differences (P<0.01) emerged for the urinary N and the total excreted N, with higher emission in Cinta Senese than in Large White breed. The difference was not significant at CP7 diet (excreted N: 19.4 vs. 17.1 g/d for Cinta Senese and Large White) but became progressively more important (P<0.01) in the diets with higher CP content (excreted N at CP16 diet: 39 vs. 35.4 g/d for Cinta Senese and Large White). Consequently, Large White retained more nitrogen than Cinta Senese (about +2.6; +3.0; +3.4; +3.8 g/d with CP7; CP10; CP13; CP16 diet, respectively; P<0.01). So, the efficiency of N utilization (retained N/absorbed N), favoured the Large White in all the tested diets (P<0.01). These results suggest to limit the CP content in diets for Cinta Senese breed, to reduce nitrogen pollution in the environment.

Effects of reducing dietary protein on the expression of nutrition sensing genes (amino acid transporters) in weaned piglets

“…Therefore, the CP level in the diet of weaned pigs has been suggested to be one of the main factors that affect their growth performance (Gallo et al, 2014), feed efficiency, and gastrointestinal health (Yin and Tan, 2010;Acciaioli et al, 2011). An increase in the entry of nutrients (e.g.…”

Chronic feeding with protein-restricted diets affect ileal amino acid digestibility and the expression of nutrient-sensing, hormone secretion, gastrointestinal digestive enzyme, and nutrient transporter genes in young weaned pigs

“…A reduction in dietary crude protein (CP) levels can reduce diarrhea and nitrogen (N) excretion and repair digestive and immune function by enhancing the gene expression levels of digestive enzymes and amino acid (AA) transporters in young pigs [4,6]. For weaned pigs, it has been suggested that the CP levels in their diets can be reduced by 2-3 points without affecting average daily gain (ADG) [4,6], feed efficiency, or gastrointestinal health when the diets are supplemented with AAs [7,8]. However, reductions exceeding 3 points have produced no effects on ADG, feed efficiency and the mRNA levels of digestive enzymes (including trypsinogen, chymotrypsin B, and dipeptidase-II and III) and AA transporters [2,4,[9][10][11][12][13], although these trends have not been observed in all studies [14][15][16].…”

Effect of varying supply of amino acids on nitrogen retention and growth performance of boars of different sire lines

“…These findings were in good accordance with the present study and may be used as explanation for the current results. Acciaioli et al (2011) reported a significant increase (P<0.01) in crude protein digestibility of pigs of the same age, but different breeds, parallel to the increase of the lysine level in the diet. These findings were in accordance with the results of the present N balance studies.…”

“…In contrast, Kass et al (1980) found a negative effect of increasing BW on digestive capacity. Freire et al (2000) and Acciaioli et al (2011) concluded that pigs are able to improve their digestive ability with increasing age. Longland et al (1994) stated that the immature gut micoflora in young pigs is responsible for the decreased apparent digestibility of some nutrients.…”