Plasma Urea Nitrogen Concentration and Growth Performance of Finishing Pigs Fed Sorghum-Soybean Meal, Low-Protein Diets

Abstract The objective of this study was to evaluate the effects of supplementing low-protein diets with sodium dichloroacetate (DCA) and glucose on growth performance, carcass traits, and meat quality of growing-finishing pigs. A total of 80 crossbred (Duroc × Landrace × Large White) growing barrows (27 ± 0.4 kg body weight) were allocated randomly to one of the five treatments during three successive 4-week periods. There were five diets in each phase. Diet 1 was the control diet with normal protein levels (CON) where protein levels in the three phases were 18%, 16.5%, and 15.5%, respectively. The dietary protein levels of Diets 2, 3, 4, and 5 (the low-protein diets, LP) were decreased by 4.5% compared to Diet 1. Additionally, Diets 3 and 4 were supplemented with an extra 120 mg/kg DCA (LP + DCA) or 1.8% glucose (LP + GLUC), respectively. Diet 5 was further supplemented with an extra 120 mg/kg DCA and 1.8% glucose (LP + DCA + GLUC). The LP + DCA diet increased the average daily weight gain of pigs compared to the CON and LP diet in phase 3 and the overall experimental period (P < 0.001). The LP diet reduced the gain:feed ratios of the pigs compared to the CON, LP + DCA, and LP + DCA + GLUC diets in phase 1 and the overall experimental period (P < 0.001). Furthermore, gain:feed ratios in LP + DCA and LP + DCA + GLUC groups did not differ from that of the CON group (P > 0.10). Pigs fed the LP + DCA diet had higher pH values of meat at 24 h post-mortem than the CON group (P < 0.05). The LP + DCA + GLUC diet increased the total protein content in the longissimus dorsi (LD) muscle of pigs, compared to the other dietary treatments (P < 0.05), and increased the Arg and Leu contents in the LD muscle compared to the LP + DCA diet (P < 0.05). Moreover, the LP + DCA diet induced a higher C18:1n9t percentage in the LD muscle of pigs compared to other groups (P < 0.05). In conclusion, an LP diet reduced the feed efficiency in pigs and barely affected meat quality, whereas 120 mg/kg DCA supplementation in an LP diet improved the growth performance of growing-finishing pigs, showed modest effects on carcass traits, and improved the muscle protein content with the addition of glucose.

Download Full-text

Nitrogen balance of starting barrow pigs fed on increasing lysine levels

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132004000100012 ◽

2004 ◽

Vol 47 (1) ◽

pp. 85-91 ◽

Cited By ~ 6

Author(s):

Ivan Moreira ◽

Alessandro Luis Fraga ◽

Diovani Paiano ◽

Gisele Cristina de Oliveira ◽

Cláudio Scapinello ◽

...

Keyword(s):

Nitrogen Balance ◽

Nitrogen Retention ◽

Nitrogen Excretion ◽

Protein Utilization ◽

Urea Nitrogen ◽

Plasma Urea ◽

Low Protein ◽

Feed Protein ◽

Protein Diets ◽

Net Protein

The effects of increasing lysine levels on nitrogen balance of pigs fed on low protein diets were evaluated. Four treatments (diets) containing lysine levels (0.8, 1.0 1.2 and 1.4%) were applied to 12 starting (20.0 ± 1.8 kg) barrow pigs. Methionine, threonine and tryptophan were kept constant to the lysine ratio in all diets. Feces and urine were collected during a 5-day period. Nitrogen output in urine (NOU), total nitrogen output (TNO), nitrogen retention (NR), net protein utilization (NPU), biological value or feed protein (BVFP), urine urea nitrogen (UUN), and plasma urea nitrogen (PUN) were determined. PUN showed high negative correlations with BVFP (-0.84), NPU (-0.76), and NR (-0.78) and a positive correlation (0.79) to NOU. Lowest nitrogen excretion and the best use of diet protein were obtained with 1.1% total lysine level. PUN is efficient to indicate amino acid for pigs.

Download Full-text

The effects of continuous intravenous and intraruminal infusions of urea on nitrogen metabolism in sheep

Australian Journal of Agricultural Research ◽

10.1071/ar9710429 ◽

1971 ◽

Vol 22 (3) ◽

pp. 429 ◽

Cited By ~ 9

Author(s):

KH McIntyre

Keyword(s):

Nitrogen Metabolism ◽

Nitrogen Balance ◽

Nitrogen Concentration ◽

Route Of Administration ◽

The Body ◽

Urea Nitrogen ◽

Plasma Urea ◽

Urea Excretion ◽

Low Protein ◽

Nitrogen Concentrations

Urea was infused into sheep both intravenously and intraruminally, and at several increasing rates. The infusions were continuous for at least 6 days for each quantity of urea infused. Three predominantly roughage rations were used. Two of these had the same roughage constituents; both had relatively low protein contents, but one contained starch. The amount of urea nitrogen retained in the body from the urea infused was greatest on the ration containing starch, when the nitrogen balance improved by as much as 4.3 g/day. The concentration of ammonia in the rumen increased linearly with the amount of urea infused by either route of administration, but was much higher in the sheep infused intraruminally. Plasma urea nitrogen concentrations increased linearly with each quantity of urea infused until they reached about 30 mg/100 ml. They increased above this concentration only in the sheep fed on the low protein roughage ration without starch. The results suggest that a renal mechanism for urea excretion may control the plasma urea nitrogen concentration at about 30 mg/100 ml under certain conditions.

Download Full-text