Effect of feeding level and dietary protein content on the growth, body composition and rate of protein deposition in pigs growing from 45 to 90 kg

Abstract

1. Eight diets of similar energy content, ranging in crude protein concentration from 95 to 256 g/kg, were given at either 2-5 or 3-2 times the energy level for maintenance to entire male pigs growing from 45 to 90 kg live weight.2. Growth rate improved with increase in feeding level and with increasing dietary crude protein up to 164 g/kg (P < 0-05). The food conversion ratio improved with each increase in dietary CP up to 186 and 164 g/kg on the lower and higher feeding treatments, respectively (P < 0-05). It was also improved with increase in level of feeding of the lower-protein diets but deteriorated with increase in level of intake of the higher-protein diets (P < 005).3. Rate of protein deposition improved with increasing dietary crude protein up to 186 and 164 g/kg on the lower and higher feeding treatments, respectively (P < 005). The results showed that, for pigs given diets deficient in crude protein, rate of protein deposition was linearly related to protein intake (P < 0-001) but independent of energy intake. For pigs given a diet adequate in crude protein, rate of protein deposition was related to energy intake and independent of crude protein intake.4. Body fat content at 90 kg decreased with increasing dietary crude protein up to 210 and 164 g/kg on the lower and higher feeding treatments, respectively (P < 0-05), and was increased by raising the level of intake of the higher-crude protein diets (P < 0-05). However, the influence of feeding level on body fat diminished as dietary crude protein was reduced.

Effects of sex and dietary lysine on performances and serum and meat traits in finisher pigs

“…That effect might also be modulated by AAs imbalance and the energy source (Tous et al, 2014). In a recent work, a total Lys restriction from 11 to 5.2 g/kg during the grower phase produced an incomplete compensatory growth in the subsequent phase and increased carcass fat depth (Suárez-Belloch et al, 2015) in agreement with previous results from other researchers (Campbell et al, 1988;Fabian et al, 2002). The effects of Lys restriction during the finisher period are more controversial.…”

“…To this respect, greater lean yield and wider loin eye area have been observed in pigs fed diets with higher Lys concentration than in those fed less Lys (Loughmiller et al, 1998;Witte et al, 2000;Bidner et al, 2004). Also, it is well documented that inadequate dietary Lys limits protein synthesis and increases the energy available for fat deposition (Campbell et al, 1988;Friesen et al, 1994). Taking into account this consideration, fatter carcasses would be expected as a response to Lys restriction but the concomitant decrease in feed intake prevented the surplus of energy for fat deposition.…”

“…It was expected because the influence of feeding Lys on carcass fat composition depends more on sex, BW or environment than on diet (Campbell et al, 1988;Friesen et al, 1994;Jin et al, 2010). …”

Salt intake and reproductive function in sheep

“…Sheep fed saltbush and barley supplement have also a higher proportion of lean meat compared to controls (Pearce et al, 2008). Lean muscle deposition is driven by a higher protein-to-energy ratio available in the diet (Searle et al, 1982;Campbell et al, 1984;Campbell, 1988), so, as described above, the increased rate of passage and protein available in response to salt intake could explain the associated increase in lean meat (Hemsley et al, 1975). It has to be noted that the pH or the color of meat or any eating quality attributes were not modified by feeding saltbush and barley supplement (Pearce et al, 2008).…”

Effect of advancing the supply of finisher diet on growth performances and carcass and pork quality of heavy barrows and gilts

“…Taking into account that the aim of the trial was increasing fatness, a slight impairment of FCR could have been carried out. In fact, in the literature, worse feed efficiency has been reported as a result of dietary protein or Lys restriction in both the grower (D'Souza et al, 2003) and the finisher phase (Campbell et al, 1984;Suárez-Belloch et al, 2015b). The result of the current work is positive, under a productive point of view, but it would indicate that the nutrient restriction generated advancing the finisher diet by 21 days was very limited.…”