Progress 04/01/99 to 09/30/04
Outputs
Three separate feeding experiments were completed to determine the digestible amino acid needs of broiler breeder hens. The objective of the research was to determine the requirement and efficiency of utilization of each amino acid for maintenance, egg production, and fertility for broiler breeder hens.The daily maintenance requirements for broiler breeders were determined by measuring the daily amino acid intake needed to produce no protein gain. The maintenance requirements were calculated as mg/d, mg/kgBCP/d and mg/ kgBW.75/d to provide requirements that would be suitable for different BW and body compositions. The maintenance requirements were: methionine, 102 mg/d, 200mg/kgBCP/d, and 55.3 mg/ kgBW.75/d; cystine, 31mg/d, 75 mg/ kgBCP/d, and 17 mg/ kgBW.75/d; phenylalanine, 230 mg/d, 414 mg/ kgBCP/d, and 112 mg/ kgBW.75/d; tyrosine, 66mg/d, 176 mg/ kgBCP/d, and 37 mg/ kgBW.75/d; lysine, 175 mg/d, 333 mg/ kgBCP/d, and 94.2 mg/ kgBW.75/d; arginine, 314 mg/d, 601 mg/
kgBCP/d, and 173 mg/ kgBW.75/d; threonine, 242 mg/d, 448 mg/ kgBCP/d, and 131mg/ kgBW.75/d; tryptophan, 21 mg/d, 36 mg/ kgBCP/d, and 11 mg/ kgBW.75/d; leucine, 205 mg/d, 400.5 mg/ kgBCP/d, and 117 mg/ kgBW.75/d; isoleucine, 159 mg/d, 319 mg/ kgBCP/d, and 92 mg/ kgBW.75/d; valine, 199 mg/d, 337 mg/ kgBCP/d, and 106.2 mg/ kgBW.75/d; and histidine, 74 mg/d, 140 mg/ kgBCP/d, and 43.6 mg/ kgBW.75/d. The amino acid production requirements for breeders (egg mass/d + body weight change/d) and the amino acid feed conversion requirements (g Feed/ g EM +g BW change) determined as 95% of maximum response of SAS polynomial regressions for each amino acid were: methionine, 409 mg/d and 436 mg/d; isoleucine, 826 mg/d and 846 mg/d; phenylalanine, 689 mg/d and 700 mg/d; lysine, 909 mg/d and 926 mg/d; and arginine, 1101 mg/d and 922 mg/d. The protein requirement (essential and nonessential amino acids) determined for production and feed conversion were 20.9g/d and 19.4 g/d. The total protein (essential
and nonessential amino acid) requirement for maintenance was determined to be 5.53 g/d which is approximately 26.5% of the total crude protein requirement for production. Previous research by our lab has shown that the percentage of amino acid requirements needed for maintenance of a 2 kg growing broiler is approximately 22% so the maintenance requirements for breeders is similar. The percentage of essential amino acids compared to total amino acids needed for maintenance is 33%. The digestible amino acid requirements for breeder production are similar to the daily requirements reported by NRC (1994) with the exception that digestible lysine is slightly higher. The requirements reported by NRC (1994) are total amino acid requirements which would make the digestible amino acid requirements reported herein approximately 10% higher if based on total amino acids. The University of Arkansas research shows that breeders fed 16% protein diets had an average of 82% fertile hatching eggs
compared to 90.5% fertile hatching eggs with a 13% protein diet.
Impacts
A 13% crude protein level in breeder I and breeder II diets would decrease the feed costs approximately 4 dollars per ton and 25 cents per breeder during the production period. The feed costs per dozen hatching eggs could be lowered by approximately 2 cents per dozen and the number of fertile hatching eggs increased eight percent from an average of 145 per breeder to 159 hatching eggs. The increased number of hatched chicks per breeder could increase by 10 increasing revenue by $3.00 per breeder. The additional hatched chicks or hatching eggs are worth significantly more than just the increased monetary value of chicks. The continuing growth of the poultry industry in Arkansas and the U.S. will require that Breeders increase the supply of quality chicks for grow-out to support the world-wide increasing demand for poultry meat. Integrators could be more selective in hatching eggs that are utilized for incubation and improve both chick quality and hatching percentage.
Publications
- Manangi, M. and C. Coon, 2004. The effect of phytase on performance of broilers fed high and low phytate phosphorus diets. Poultry Sci. 83: Supplement 1, p150.
- Lu, J., J. P. McMurtry, and C.N. Coon, 2004. Developmental changes of plasma insulin, glucagons, IGF-I, IGF-II, thyroid hormones, and glucose concentration in chick embryo. Poultry Sci. 83: Supplement 1, p192
- Lu, J. and C. N. Coon, 2004. Developmental changes of hepatic enzymes activities involved in methionine metabolism for chick embryo. Poultry Sci. 83: Supplement 1, p192-193.
- Sun, J.M., M. DeBeer, N. K. Sakomura, and C. Coon, 2004. Methionine, cystine, phenylalanine, tyrosine, and non-essential AA maintenance requirements for broiler breeders. Poultry Sci. 83: Supplement 1, p314-315.
- Sun, J.M., M. DeBeer, K. Bramwell, and C. Coon, 2004. Amino acid requirements for broiler breeders at peak production. Poultry Sci. 83: Supplement 1, p317.
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Progress 01/01/03 to 12/31/03
Outputs
The daily energy requirement for broiler breeders is important because breeders are fed restricted amounts of feed. The breeders need to be fed adequate metabolizable energy for egg production and small increases in weight gain but keep them from gaining excessive weight because overweight and obese breeders are less capable of producing fertilized hatching eggs. The ability to control body weight gain for the modern high yield type breeder is much harder than in the past because of their extreme efficiency in using nutrients for breast meat gain. The largest part of daily energy required for breeders is primarily used for maintenance, which is dependent upon temperature and body weight. Metabolizable energy studies were conducted with breeders in environmental temperatures of 15.5, 23, and 30C which showed the daily maintenance requirements were 104.3, 98, and 99.4 kcal ME/kg BW0.75 , respectively. The research shows the energy requirement goes up in cooler
temperatures to maintain body temperature and also goes up slightly in hot temperatures to help the breeder dissipate the body heat. The estimated efficiency for energy required for egg synthesis was 73% for all temperatures. The body weight gains were partitioned into fat and protein gain with efficiencies for fat and protein retention determined to be 0.77 and 0.37, respectively. The information for efficiency of energy utilized for egg synthesis, efficiency for producing both protein and fat BW gain, and the maintenance energy requirements at different temperatures was utilized in developing an equation for predicting the ME required for breeders in production. The prediction equation was prepared to support the daily metabolizable energy needs for all modern high yield strains with different BW, producing different weights and numbers of hatching eggs and housed in different environmental temperatures. The prediction equation is the following: ME=BW0.75 [111.02 - 0.49 T + 0.049
(T-22.07)2 ] + BWD (1/0.77 x ERf + 1/0.37 x ERp) + ECE/0.73 x EM. ME is metabolizable energy, BW0.75 is metabolic body weight, T is temperature in C, BWD is body weight change (g/d), ERf is energy retained in body weight gain as fat (kcal), ERp is energy retained in body weight gain as protein (kcal), ECE is energy content of eggs (kcal/g), and EM is egg mass (g). The equation predicts a breeder at 31 wks at peak egg production weighing 3.33kg with a BW change of 2.14 g/d producing an average of 46.86g/d of hatching eggs would need 366 kcal ME day. Since the partitioning studies were conducted with individual hens in cages, an additional 48.4 kcal or 20% of maintenance ME for physical activity was added for breeders housed on the floor in commercial conditions. Primary Breeders for different strains of breeders recommend between 435-460 kcal per day for their breeders at peak egg production. The ME partitioning research indicates breeders at peak production only need 416 kcal per day
and are being fed from 21 to 46 kcal per day too much energy.
Impacts
The 21 to 46 kcal of excess energy being fed to broiler breeders throughout a 40 wk production period is an annual loss of 24.8 to 54.4 cents per breeder based on the current costs of an energy source such as poultry fat. The overall savings in dietary energy costs for the 75 million breeders in the US in production for a 40 wk period would be between 18.6 and 40.87 million US dollars. Besides the savings in feed costs, an additional economic impact would be the high probability of producing less hatched chicks per breeder because of known fertility and hatchability problems associated with overweight breeders.
Publications
- Richards, M.P., S.M. Poch, C.N. Coon, R.W. Rosebrough, C.M. Ashwell and J. McMurtry, 2003. Feed Restriction significantly alters lipogenic gene expression in broiler breeder chickens. J. Nutrition 133:707-715.
- Silva, R., N.K. Sakomura, H.P. Couto, C. Coon and C.R. Pacheco, 2003. Modelling metabolizable energy utilization in broiler breeder pullets. Poultry Sci. 82:419-427.
- Sakomura, N. K. and C. Coon, 2003. Amino acid requirements for maintenance of broiler breeder pullets. Pages 280-281 in World's Poultry Science, 14th European Symposium on Poultry Nutrition. Lillehammer, Norway.
- Manangi, M. and C. Coon, 2003. Effect of phytase on phytate phosphorus retention in broilers fed diets containing different levels of Ca and P. Poultry Sci. 82: Supplement 1, p74.
- Manangi, M. and C. Coon, 2003. Influence of graded levels of dietary phytase on phytate phosphorus retention in broilers. Poultry Sci. 82: Supplement 1, p74.
- Manangi, M., J. Lu, and C. Coon, 2003. Evaluation of soybean meal samples from different sources in the U.S. using phytase enzyme. Poultry Sci. 82: Supplement 1, p75.
- McMurtry, J.P., D.M. Brocht, C. Ashwell, P. Allen, R. Leach, and C. Coon, 2003. The development of a homologous radioimmunoassay for chicken leptin. Poultry Sci. 82: Supplement 1, p84.
- Sun, J.M. and C. Coon, 2003. Broiler ideal amino acid profile as determined with uric acid excretion, amino acid accretion, and nitrogen retention.. Poultry Sci. 82: Supplement 1, p73.
- Sakomura, N.K., M. Reyes, J.B.K. Fernandes, and C. Coon, 2003. Amino acid maintenance requirements for broiler breeder hens. Poultry Sci. 82: Supplement 1, p72.
- Sakomura, N. K., M. Manangi, J.B.K. Fernandes, and C. Coon, 2003. Lysine requirements for maintenance and for tissue protein accretion in broiler breeders. Poultry Sci. 82: Supplement 1, p75.
- Reyes, M, and C. Coon, 2003. Broiler breeder hen metabolizable energy requirements for maintenance and efficiency of utilization for producing egg calories. Poultry Sci. 82: Supplement 1, p72.
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Progress 01/01/02 to 12/31/02
Outputs
The nutrient requirements for broiler breeders need to be factorially partitioned into maintenance, egg production, and weight gain in order to provide meaningful current and future requirements for breeders that can be used for different environments, genetic strains, egg production levels, egg size and body composition. The maintenance requirements for 10 essential amino acids were determined in 560 sexually immature 23 wk old breeders by estimating the regression of daily protein accretion vs. daily amino acid intake at the end of a three week feeding period. The amount of each amino acid needed to maintain nitrogen equilibrium was calculated as the x-intercept of the regression. The daily maintenance requirements (mg/kg metabolic BW) for lysine, methionine, arginine, threonine, tryptophan, phenylalanine, leucine, isoleucine, valine, and histidine were determined to be:94.2, 56.5, 173.1, 130.6, 10.7, 163.9, 117.1, 92.4, 106.2, and 43.6. The maintenance requirements
for metabolizeable energy (ME) and the efficiency of utilization of ME for converting to egg calories was determined with 53 wk old breeders. Individual breeder hens were taken out of production with an estrogen receptor blocker for maintenance studies and then after egg production was resumed the efficiency of dietary calories for producing egg calories above the maintenance requirement was determined. The daily maintenance requirement was determined to be 99 kcal ME/kg metabolic BW when the breeders were housed at 21C. The efficiency of converting dietary ME calories to egg calories was determined to be 65%. The University of Arkansas cooperating with a USDA Beltsville laboratory reported significant metabolic and endocrine changes that occur in breeders fed either ad lib or fed restricted levels of feed. Presently, breeders must be control fed during the rearing period and during the production period to keep breeders from becoming too fat thus decreasing egg production and
fertility. Expression of sterol regulatory element binding protein 1, ATP-citrate lyase, fatty acid synthase, malic enzyme, acetyl-CoA carboxylase, and stearoyl-CoA desaturase 1 genes in ad lib birds declined from their highest levels just prior to photostimulation to reduced levels as the birds came into and maintained egg production. In contrast, the restricted birds displayed a dramatic increase in the expression of these genes following photostimulation at first egg with a subsequent decline in expression levels as they reached peak egg production. Expression of fatty acid binding protein, very low density apolipoprotein II and apolipoprotein B genes increased in both ad lib and restriction fed breeders following photostimulation, whereas apolipoprotein AI gene expression declined in both groups. These changes are consistent with increased hepatic lipid transfer capacity toward yolk during egg production. The ad lib and restricted feeding regimes produced significantly different
effects on hepatic gene expression related to lipid metabolism in broiler breeders.
Impacts
The determination of broiler breeder requirements for amino acids and metabolizeable energy using factorial methods will provide information the poultry industry can utilize for their specific genetic breeder strains, production potential, and environment. By analyzing breeder pullet and hen expression of specific hepatic genes involved in lipogenesis and lipid transport as well as other metabolic pathways, it may be possible to develop a better feeding system with optimum dietary nutrient requirements for growth, body composition and performance of broiler breeders.
Publications
- Seo, S. and C. Coon, 2002. Measurement of protein synthesis rate in broiler breeder pullets and hens using 13C, 15N - Leucine bolus injection by HPLC/MS. Poultry Sci. 81:Supplement 1, p 92.
- Sun, J.M. and C. Coon, 2002. The effect of body weight, dietary energy density, and feed withdrawal rate on performance of broiler breeders. Poultry Sci. 81:Supplement 1, p 101.
- Coon, C. and K. Leske, 2002. The availability of calcium and phosphorus in feedstuffs. Pages 151-179 in :Poultry Feedstuffs, Supply, Composition and Nutritive Value, (Eds.) J. McNab and K.N. Boorman, CAB International, UK.
- Leske, K. and C. Coon, 2002. The development of feedstuff retainable phosphorus values for broilers. Poultry Sci. 81:1681-1693.
- Richards, M.P., S.M. Poch, C.N. Coon, R.W. Rosebrough, C.M. Ashwell and J. McMurtry, 2002. Feed restriction significantly alters lipogenic gene expression in broiler breeder chickens. J. Nutrition 133: (In Press)
- Seo, S. and C. Coon, 2002. The determination of retainable phosphorus, relative biological availability, and relative biological value of phosphorus sources. Poultry Sci. 81:Supplement 1, p 74.
- Sun, J.M. and C. Coon, 2002. Broiler ideal amino acid profile as determined with broken line, exponential, and polynomial models. Poultry Sci. 81:Supplement 1, p 74.
- Sakomura, N.K. and C. Coon, 2002. Amino acid requirements for maintenance for broiler breeder pullets. Poultry Sci. 81:Supplement 1, p 91.
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Progress 01/01/01 to 12/31/01
Outputs
A large range of body weights, body compositions and state of maturity of broiler breeders in a flock make it difficult to maximize performance. Egg production for sexually mature breeders requires significantly more dietary energy and protein than nutrients needed for controlling body weight of non-sexually mature breeder pullets. Research at the University of Arkansas recently determined that lighter weight pullets gained significantly more weight compared to the heavier pullets prior to flock peak production and throughout the laying cycle. However, the percent mortality, hatching egg production, feed conversion, and egg weight from the initially lighter breeder pullets through a complete 40 week production period was equal or numerically better than earlier maturing standard body weight pullets. A more aggressive reduction in daily feed intake, after peak production, did not affect egg production or egg weight and numerically improved feed conversions for each of
the body weight groups of breeder hens. The aggressive reduction in feed intake allowed the base line feed intake to be reached at 45 weeks of age compared to 50 weeks with a more standard withdrawal rate. The breeder hens that had feed reduced at the faster rate required 5 g less feed per hatching egg and approximately 7 g less feed per hatching chick. All breeder pullets in the Arkansas research study, including all body weight groups, produced approximately 8 additional hatching eggs per breeder and 5 additional hatched chicks per breeder compared to the Breeder Standard for the breeder hen. In order to successfully produce sexual maturity and cause breeder pullets to come into persistent production with photostimulation, breeder pullets need to reach a physiological threshold and have adequate fleshing with optimum levels of protein mass and fat tissue available. The University of Arkansas and a USDA Beltsville laboratory are presently cooperating on research to determine the
relationship of dietary nutrient intake, body composition, lipogenic enzymes, and metabolic hormones for broiler breeders both before and after photostimulation, first egg, and peak production. The research indicates there is a significant relationship of breeder body fat with plasma insulin/glucagon ratio, insulin-like growth factors I and II. Egg producers may be able to monitor the physiological status of a flock by metabolic hormone levels. Improved methods of determining phosphorus requirements of a broiler breeder flock are needed to reduce feeding costs and decrease phosphorus in poultry waste. Research at the University of Arkansas has shown that retention of feed grade phosphate is 80-90 % when fed at approximately one-half dietary requirement but retention drops to 50-60 % when feeding phosphorus levels suggested by NRC (1994). The feeding of higher levels of phosphorus may cause positive responses for performance but there will be known phosphorus losses in the excreta.
Economic decisions can be made about the optimum level to feed for maximum performance if integrators know the overall losses of phosphorus and possible penalties for those losses.
Impacts
Optimum feeding conditions and a more aggressive feed withdrawal program following peak production for breeder hens could save feed costs and provide five additional hatched chicks per breeder. The additional hatched chicks or hatching eggs would substantially increase the gross income per breeder and also allow hatcheries to be more selective in hatching eggs utilized for incubation and improve both chick quality and hatching percentage.
Publications
- Coon, C. and K. Leske, 2001. The availability of calcium and phosphorus in feedstuffs In: Poultry Feedstuffs, Supply, Composition and Nutritive Value, Ed. J. McNab, CAB International, UK. (In Press)
- Coon, C.,2001. Chapter 14, Digestion and metabolism. Pages 199-214 In: Commercial Chicken Meat and Egg Production, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X
- Coon, C.,2001. Chapter 15, Major feed ingredients:feed management and analysis. Pages 215-242. In: Commercial Chicken Meat and Egg Production, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X
- Coon, C.,2001. Chapter 16, Broiler nutrition. Pages 243-266 In: Commercial Chicken Meat and Egg Production, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X
- Coon, C.,2001. Chapter 17, Feeding egg-type replacement pullets. Pages 267-286 In: Commercial Chicken Meat and Egg Production, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X
- Coon, C.,2001. Chapter 18, Feeding commercial egg-type layers. Pages 287-328 In: Commercial Chicken Meat and Egg Production, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X
- Coon, C.,2001. Chapter 19, Feeding broiler breeders. Pages 329-370 In: Commercial Chicken Meat and Egg Production, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X
- Seong, S. and C. Coon, 2001. High performance liquid chromatographic determination of homocysteine and cystathionine in tissues by derivatization with 6-aminoquinollyl-N-hydroxylsuccinimidyl carbamate. American Chemical Society, 222nd ACS National Meeting, Abstracts of papers, Part 1, 0-8412-3803-0, ab. no. 75.
- Coon, C.,2001. Chapter 20, Vitamins, minerals and trace ingredients. Pages 371-394 In: Commercial Chicken Meat and Egg Production, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X
- Leske, K. and C. Coon, 2001.The development of feedstuff retainable phosphorus values for broilers. Poultry Sci.80: (In press)
- Richards, M.P., S.M. Poch, C.N. Coon, Y. Kirby, R.W. Rosebrough, C. M. Ashwell, and J.P. McMurtry, 2001. Expression of selected hepatic genes related to lipid metabolism in broiler breeders. Poultry Science 80:Supplement 1,p393
- Seong, S. and C. Coon, 2001. High performance liquid chromatographic determination of phytic acid in biological samples. American Chemical Society, 222nd ACS National Meeting, Abstracts of papers, Part 1, 0-8412-3803-0, ab. no. 91.
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Progress 01/01/00 to 12/31/00
Outputs
The ability to control fat deposition of breeders during the rearing and production period in order to maximize the production of hatchable chicks is a difficult problem. Breeders are thought to need an unknown amount of fat and protein in their body composition along with a chronological age requirement in order for photostimulation to successfully produce sexual maturity. Breeders need to be control fed from two weeks of age through the production period to minimize the breeders propensity to gain fat and become obese. Leptin in mammals has been found to be a key appetite controlling factor shown to reflect the body composition and also necessary for the development of sexual maturity. Research is being conducted to determine the significance of body composition, lipogenic enzyme expression, and leptin levels to better understand the complexity and importance of fat deposition in breeders. With the collaborative effort of USDA Beltsville, two leptin projects have
been conducted with the University of Arkansas. In the first leptin study, breeder hens were fed free choice to determine the relationship of leptin expression in liver and fat tissue compared to appetite. Breeders with the largest ad libitum feed intake per metabolic weight had 90% lower leptin expression levels in subcutaneous fat and in the liver compared to breeders with a less intake/ metabolic weight. In a second leptin study, restriction fed and ad libitum fed breeders were evaluated for gene expresson for lipogenic enzymes, metabolic hormones and leptin receptor gene expression prior to photostimulation, two and one-half weeks post lighting, at first egg, and 36 and one-half weeks. The gene expression for fatty acid synthetase, malic enzyme, acetyl-CoA carboxylase, fatty acid binding protein, and metallothionein, were significantly lower for restriction fed breeders compared to ad libitum fed breeders for the prestimulation and plateau laying period however the gene expression
of lipogenic enzymes in most cases were significantly higher for restriction fed breeder hens at first egg. The restriction fed breeders had 5.8 fold more glucagon and 2.3 fold less insulin compared to ad libitum fed breeder pullets prior to photostimulation. The goal of the research is to provide a scientific method of determining when a flock has reached a mature body weight and the physiological threshold needed to successfully produce sexual maturity. Research at the University of Arkansas and the University of Minnesota has shown that phosphorus requirements of poultry need to be evaluated in a different way in order to decrease overfeeding phosphorus and to lower feed cost. A phosphorus retention assay has been developed that shows reagent grade dicalcium phosphate monohydrate is retained at a 82.8% when fed at levels below the suggested NRC requirement but retained at a 60.3% rate at the NRC 0.45% non-phytate phosphorus requirement. Understanding the biological model producing
different phosphorus retention with changing phosphorus intake will allow nutritionist to formulate for minimum phosphorus excretion and optimum economical performance.
Impacts
The poultry industry of Arkansas and the nation would gain if a system existed to determine when breeder pullets are physiologically ready for sexual maturity. The ability to sexually stimulate pullets at the correct time to coordinate with body reserves would produce higher peaks in production and also keep persistency of lay higher without overfeeding. Flocks may also be monitored throughout the laying/breeding cycle to coordinate lipogenic enzyme expression with leptin levels and body composition, providing a much more scientific way to control feed intake to keep breeders from becoming fat during the period of 31-65 weeks of age. Conservatively, if each breeder flock could produce an average of three additional hatching eggs per breeder, the increased income in Arkansas alone would be tremendous. The entire poultry industry will gain from having a system by which nutritionists can determine how much feedstuff phosphorus will be retained and how much will be lost
in the excreta. The feeding of specific levels of phosphorus may cause positive responses for performance, but there will be known phosphorus losses in the excreta. Economic decisions could be made about the optimum level to feed for maximum performance if integrators know the overall losses of phosphorus and possible penalties for those losses.
Publications
- Coon, C. and K. Leske, 2000. The availability of calcium and phosphorus in feedstuffs In: Poultry Feedstuffs, Supply, Composition and Nutritive Value, Ed. J. McNab, Nottingham University Press, Loughborough, Leicestershire, UK. (In Press)
- Coon, C.,2000. Chapter 14, Nutrient classification:digestion and metabolism. In: Commercial Chicken Meat and Egg Production Manual, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X(In Press)
- Coon, C.,2000. Chapter 15, Major feed ingredients:feed management and analysis. . In: Commercial Chicken Meat and Egg Production Manual, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X(In Press)
- Coon, C.,2000. Chapter 17, Feeding egg-type replacement pullets. In: Commercial Chicken Meat and Egg Production Manual, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X(In Press)
- Coon, C.,2000. Chapter 18, Feeding commercial egg-type layers. . In: Commercial Chicken Meat and Egg Production Manual, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X(In Press)
- Coon, C.,2000. Chapter 19, Feeding broiler breeders. . In: Commercial Chicken Meat and Egg Production Manual, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X(In Press)
- Coon, C.,2000. Chapter 20, Vitamins, minerals and trace ingredients. In: Commercial Chicken Meat and Egg Production Manual, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X(In Press)
- Coon, C., 2000. Enhanced soybean meal in poultry feeds:economic implications. Proceedings MN Nutr. Conf. p52-63. Bloomington, MN
- Coon, C. 2000. Amino acid requirement of broiler breeders. Proceedings Arkansas Nutr. Conf. p1-21. Fayetteville, AR
- Coon, C.,2000. Chapter 16, Broiler nutrition. . In: Commercial Chicken Meat and Egg Production Manual, 5th Edition, Eds D. Bell and B. Weaver, Kluwer Academic Publishers, Norwell, Massachusetts. ISBN:0-7923-7200-X(In Press)
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Progress 01/01/99 to 12/31/99
Outputs
A collaboriative experiment with USDA Beltsville was conducted to determine leptin levels in breeder pullets just prior to lay. Leptin is a hormone that regulates obesity in animals by regulating food intake based on body mass and fat composition and is also necessary for sexual maturity. Leptin hormone values were determined by measuring leptin mRNA in fat and liver tissue of breeder pullets fed free choice prior to egg production. The leptin levels in breeder pullets that eat as much as two times more feed per unit body weight were 90% less than breeder pullets consuming less feed. The goal of the ongoing research is to provide a scientific method of determining when a flock has reached a mature body weight and physiological threshold that is needed to successfully produce sexual maturity. A 5 day chick retention assay was developed to determine the amount of non-phytate phosphorus and phytate phosphorus that are retained from individual feedstuffs. The non-phytate
and phytate phosphorus retention from feedstuff depends upon levels of phosphorus in the diet. The assay indicates phosphorus excretion is greatly increased when phosphorus intake exceeds the amount necessary for reaching a physiological steady state level. The research indicates non-phytate phosphorus from cereal and legume sources may be 66% retained whereas only 25-30% of the phytate phosphorus from these feedstuffs was retained. Commercial phytase added to the feed increased the total phytate phosphorus retention to 50-60%. The amount of dietary phosphorus needed for the physiological inflection point for phosphorus retention needs to be considered in determining phosphorus requirements for poultry in order to decrease over feeding phosphorus and lower feed cost. The phosphorus retention assay will help nutritionist access the true need for dietary phosphorus and to determine the most economical levels to feed. Research was conducted to determine the effect of removing
oligosaccharides from soybean meal by extracting the meal with 80% ethanol. The oligosaccharides in soybean meal have been shown to increase the passage rate of digesta in poultry and are of no nutritional value. The metabolizable energy of soybean meal was improved 350 kcal ME/kg and digestible amino acids increased by 4 percentage points after the oligosaccharides were removed. A system was developed to measure the potential production of hydrogen gas in chicks fed soybean meal and soybean meal with oligosaccharides removed. The chicks fed regular soybean meal produced 3.2 times more hydrogen gas and produced the gas 10 hours earlier compared to the chicks fed ethanol extracted soybean meal. The research shows that the regular soybean goes through the digestive tract much quicker thus lowering the time needed for optimum nutrient absorption. The improvement in the nutritional value of soybean meal would lower the cost of feed by lowering the amount of protein, amino acids, and
energy presently being added to the diet to compensate for lower nutrients in soybean meal.
Impacts
The poultry industry would gain if a system could be used to determine when breeder pullets are physiologically ready for sexual maturity. The ability to sexually stimulate pullets at the correct time to coordinate with body reserves would produce higher peaks in production and also keep persistency of lay higher without overfeeding. The overall feed cost of producing hatching eggs with breeders can be reduced if the nutritional value of soybean meal can be improved and a the overfeeding of phosphours can be reduced.
Publications
- Coon, C. and K. Leske, 1999. The availability of calcium and phosphorus in feedstuffs. In: Poultry Feedstuffs, Supply, Composition and Nutritive Value, Ed. I. McNab, Nottingham University Press, Loughborough, Leicestershire, UK. (In Press)
- Leske, K. and C. Coon, 1999. Nutrient content and protein and energy digestibilities of ethanol-extracted, low a-galactose soybean meal as compared to intact soybean meal. Poultry Sci. 78:1177-1183.
- Leske, K. and C. Coon, 1999. A bioassay to determine the effect of phytase on phytate phosphorus hydrolysis and total phosphorus retention of feed ingredients as determined with broilers and laying hens. Poultry Sci. 78:1151-1157.
- Leske, K. and C. Coon, 1999. Hydrogen gas production of broiler chicks in response to soybean meal and a-galactoside free, ethanol-extracted soybean meal. Poultry Sci. 78:1313-1316.
- Cheng, T. K., M. L. Hamre, and C. N. Coon, 1999. Effect of constant and cyclic environmental temperatures, dietary protein, and amino acid levels on broiler performance. J. Applied Poultry Res. 8. No.4: 426-439.
- Ashwell, C. M., J. P. McMurtry, and C. Coon, 1999. Leptin expression in broiler breeder hens. Poultry Sci. 78:Supplement 1, 395 abst.
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