The effect of body weight and energy intake on the composition of deposited tissue in pigs

Abstract

Many pig growth models assume that there is no effect of energy intake and of body weight on the ratio of lipid to protein deposition rate in pigs below their maximal protein deposition rate. An experiment was performed to check whether an effect of body weight and of amount of energy intake on this partitioning of energy is indeed absent when protein deposition is limited by energy intake. Two constant amounts of energy were given above maintenance requirement (12·6 and 16·3 MJ digestible energy (DE) per day for production, treatment L and H, respectively). A total of 52 entire male pigs were slaughtered at 25,45, 65, 85 or 105 kg live weight. Results showed that, for both levels of intake, the ratio of lipid to protein deposition rate increased with increasing body weight. At the L energy intake, the ratio of lipid to protein deposition rate increased from 0·74 at 25 kg to 0·99 at 105 kg body weight. In animals receiving the H treatment, the ratio of lipid to protein deposition rate increased from 0·82 to 1·35 in that weight range. This change in nutrient partition was also reflected in daily gain. Daily gain declined with increasing live weight, a decrease of 150 g/day over the weight range 25 to 105 kg. The 3·7 MJ DE difference in energy intake between treatment H and L resulted in an average overall difference of 105 g daily gain. A control group fed ad libitum showed that protein deposition capacity was above 200 g/day, thus the pigs at the L and H treatment were below their protein deposition capacity. It was concluded that both live weight and energy intake influence the ratio of lipid to protein deposition rate. The mechanism of partitioning between lipid and protein deposition below maximal protein deposition capacity needs further specification in order to improve the predictions of growth models which use the linear-plateau concept.

Metabolizable energy requirement for starting barrow pigs (15 to 30 kg) fed on the ideal protein concept based diets

“…In our experiment, an increase in fat content and fat deposition rate, along with the highest ME levels, was observed; which indicated that above 3,264 kcal ME, there was a surplus of energy higher than requirements for protein deposition; also, the excess resulted in fat storage. The same result was found by Greef et al (1994) who observed that above maximum capacity of protein deposition, the high daily energy intake caused increase in the carcass's lipid:protein ratio. Being the pigs from the dam line hybrids, their maximum capacity of protein deposition was achieved at 3,264 kcal of ME/kg or less.…”

Effect of age at slaughter on carcass traits and meat quality of Italian heavy pigs1

“…An age effect was detected for growth and carcass parameters (P < 0.01); the decrease in growth rate of pigs older than 8 mo is in agreement with the wellknown effect of the increase in age and slaughter weight on pig performance (De Greef et al, 1994;Whittemore 1994;Candek-Potokar et al, 1998). Previous research studies performed on heavy pigs (Bittante et al, 1990;Franci et al, 1994a) did not show consistent differences in growth rate between pigs slaughtered at different ages and weights, but the dietary regimens were not reported and the compared slaughtering weights were lower than in the present trial (110 to 145 and 131 to 159 kg, respectively, vs. 143 to 182).…”

Performance and body composition of finishing gilts (45 to 85 kilograms) as affected by energy intake and nutrition in earlier life: II. Protein and lipid accretion in body components.

“…The ratio between lipid and protein deposition (LD: PD) increased curvilinearly from approximately .5 at the lowest intake level to 2.2 at the higher intake levels. This increase in LD:PD with increasing energy intake has been reported earlier for young and older pigs (Campbell et al, 1983b;De Greef et al, 1994;Bikker et al, 1995). Nevertheless, it is often assumed that below PD max the LD:PD is constant and independent of energy intake.…”