Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by Q. Jiang
Total Records ( 4 ) for Q. Jiang
  Q. Jiang , P.W. Waldroup and C.A. Fritts
  Reduction of the dietary crude protein (CP) by amino acid supplementation is effective to a point but performance eventually declines. This study was conducted to determine if supplementation with certain amino acids that serve as precursors to metabolites involved in the urea cycle or the formation of essential amino acids might improve the performance at low protein levels. Diets were formulated to meet 100% or 110% of NRC recommendations for essential amino acids with Lys at 110% or 120% of recommendations. The CP levels were 16, 18, 20, 22 or 24%. The CP and ME equivalency values of amino acids were considered in the formulation. A minimum dietary electrolyte balance [(Na+K)-Cl)] of 200 meq/kg was maintained. Amino acids added to the low CP diets included: 1) Gly; 2) Gly + Arg; 3) Gly + Pro; 4) Arg + Pro; 5) Gly + Arg + Pro; 6) Gly + Arg + Pro + Glu. The Gly, Arg, and Pro were added at 0.2% while Glu was added at 0.4%. Each dietary treatment was fed to six pens of five male chicks from 1 to 21 d. Feeding diets with less than 22% CP resulted in loss in the body weight (BW) and impaired the feed conversion ratio (FCR) regardless of the amino acid status. Supplementation of low CP diets with Gly significantly improved the performance of broilers but did not reach that obtained on diets with 22 or 24% CP. None of the other amino acid supplements consistently influenced the performance of chicks in the absence of Gly. These data suggest that Gly may be a limiting factor in diets low in CP. It is likely that some of the requirements for lesser researched essential amino acids may be insufficient to support performance at lower levels of crude protein.
  P.W. Waldroup , Q. Jiang and C.A. Fritts
  A study was conducted to evaluate effects of dietary crude protein (CP) level and Gly and Thr supplementation on performance of male broiler chicks during the period of 0 to 21 days. Diets were formulated based on NRC (1994) recommendations (Lysine at 110% of suggested level). All diets were formulated to contain 3,200 ME kcal/kg. A minimum dietary electrolyte balance of 250 meq/kg was stipulated with a minimum of 0.25% sodium and 0.20% chloride. Five primary diets were formulated to contain 16%, 18%, 20%, 22%, and 24% CP. The diets were then supplemented with additional 0, 0.2%, 0.4% Gly or 0, 0.2%, 0.4% Thr in all possible combinations resulting in a 5x3x3 factorial arrangement. Each of the 45 treatments was fed to six replicate pens of five male commercial broilers. The test diets and tap water were provided for the ad libitum consumption from 1 to 21 d of age. At 21 d of age body weight and feed consumption were determined. Reducing dietary protein below 22% significantly reduced 21 d BW and depressed feed conversion. Addition of 0.2 or 0.4% Gly significantly improved BW and numerically improved feed conversion at lower levels of protein but at protein levels of 20% or more the basal diets appeared to provide sufficient Gly. These data suggest that requirements for Gly suggested by NRC (1994) are inadequate in diets with low CP. Thr supplementation was ineffective in improving performance at low CP levels suggesting that the present recommendations of NRC (1994) are adequate. Mortality did not vary significantly among chicks receiving all experimental diets.
  P.W. Waldroup , Q. Jiang and C.A. Fritts
  Reduction of dietary crude protein (CP) with amino acid supplementation has been effective in reducing the cost of poultry feed. However, the performance of broilers declines when CP levels reaches a point and can not be totally restored with amino acid supplementation. This study was conducted to determine if differences in feed intake were responsible for the reduced performance at low protein levels. Diets were formulated to meet 100% of NRC (1994) recommendations for indispensable amino acids (Lys at 110%) with CP levels of 16%, 18%, 20%, 22% or 24% with the CP and metabolic energy (ME) equivalency values of amino acids considered in the diet formulation. A minimum dietary electrolyte balance of 200 meq/kg was maintained. There were two feeding regimes including ad libitum feeding and control feeding with a total of ten treatments. All birds were provided a complete 24% CP diet ad libitum from one to 7 d. At 7 d chicks were weighed and placed on test diets containing the various levels of CP. One group remained on ad libitum feeding while the other group was control fed. Feeding diets with less than 20% CP resulted in the loss of BW and impaired feed conversion ratio (FCR) regardless of feeding regimes. There was no significant difference in feed intake and mortality among different dietary treatments in both feeding regimes. Reduction in feed intake does not appear to be the cause of reduced performance on diets low in CP.
  P.W. Waldroup , Q. Jiang and C.A. Fritts
  A study was conducted to evaluate the effects of adding all essential amino acids (EAA) equal to that of higher CP diets or a mixture of nonessential amino acids (NEAA) to low CP diets on the live performance of broilers during the period of 0 to 21 d. A series of experimental diets comprised primarily of corn and soybean meal were formulated to contain 3,200 ME kcal/kg. Five primary diets were formulated to contain 16, 18, 20, 22, and 24% CP. Requirement levels for EAA (110% of NRC, 1994) were accomplished when necessary by adding crystalline amino acids. In each of these dietary series, diets with 16, 18, and 20% CP were supplemented with additional EAA (Trp, Ile, His, Val, Leu, Arg, Gly and Phe) to bring the content of all these EAA to a level equal to that of the 22% CP diet. Additional diets in each series with 16, 18, and 20% CP were supplemented with a mixture of NEAA (equal parts of Ala, Glu, and Glu-NH2) to provide levels of nitrogen equivalent to that provided by the EAA supplementation in the previous diets. Each of the treatments was fed to 12 replicate pens of 5 male chicks of a commercial broiler strain. The reduction of CP level in the starter diets had a significant influence on the live performance. Decreasing CP levels lower than 22% significantly decreased BW gain and increased the feed conversion ratio (FCR). Adding the EAA or NEAA mixtures to the low CP diets significantly improved the performance but did not completely overcome the adverse effects of the low CP diets.
 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility