Metabolizable Energy of Sunflower Kernels in Goffin’s Cockatoo

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The comparative whole carcass amino acid composition of the chicken to a small parrot, the bugerigar shows a similarity which may allow the use of broiler requirements as estimates of parrot amino acid requirements.

A Review of the Amino Acid and Fatty Acid Composition of Oil Seeds Eaten by Parrots

Summary

The proximate analysis of the seed kernels of sunflower, safflower and peanut, common food for captive parrots, indicated that they contain very high fat and moderate protein levels with comparably high gross energies. The metabolizable energy value of sunflower seed kernel in caged Goffin’s Cockatoos was 6,207 ± 282 kcal/kg when determined in an ad libitum total collection trial and 6,094 ± 86 kcal/kg when determined by force feeding with total collection. The mean daily existence metabolism for the Goffin’s under caged maintenance conditions was 48 kcal/day/bird or 186 kcal/day/kg. This is about 2.2 times the basal metabolic rate predicted for these birds.

When comparing the essential amino acid profile for growth requirements in poultry to the levels found in oilseed kernel protein it appears that lysine and methionine are limiting in all three seeds examined plus threonine is also limiting in safflower and peanut protein. The comparative whole carcass amino acid composition of the chicken to a small parrot, the bugerigar shows a similarity which may allow the use of broiler requirements as estimates of parrot amino acid requirements.

goffin cockatoo
Goffin’s Cockatoo (Cacatua goffini)

INTRODUCTION

A recent nationwide survey of pet owners determined that 71 to 77% of bird owners purchased boxed or bagged seed with only 10% purchasing pellets.1 Yet few scientific studies have been performed on the nutritional value of these seeds. The guaranteed analysis on a seed package does not provide much information as to the nutritional value of the mix as it includes the high fiber hulls which parrots do not eat.

Additionally most birds will select their favorite seeds out of a mix before eating the other ingredients, if they eat them at all. Thus each mixture of seeds may provide different nutrient levels depending on the final ratio of seeds and other ingredients eaten by the bird. The oilseeds sunflower and safflower represent the major portion of most parrots’ diets fed seed mixes as they are common ingredients and preferred by the birds over other seeds. Several varieties of sunflower are commercially grown. Oil-type seeds are grown to yield edible oil and high fiber protein meal. Whole confectionery seeds have loose kernels within the hull and are lower in oil because they have a higher fraction of hull.2 Both forms are included in seed mixes with the confectionery seed being more common.

The dietary energy which the bird can utilize is referred to as metabolizable energy (ME).3 Caloric need is the main factor controlling feed intake. Therefore knowing the daily energy requirements, and the ME value of a diet is helpful when formulating for a proper balance of vitamins, minerals and protein as the levels of these nutrients are based on the feed intake.

Gross energy (GE) represents the release of heat when a substance is completely oxidized and does not provide direct prediction of utilization of energy by a given animal.4 Apparent digestible energy (DE) is the GE of the feed consumed minus fecal energy.4 Fecal and urinary waste mix in the cloaca of birds before being voided thus DE is difficult to study in birds. The apparent metabolizable energy (AME), the most widely used measure of food energy available to birds, can be determined by subtracting by the energy of the excreta (fecal + urinary) from the GE of the feed eaten and dividing by the weight of the feed eaten.3 True ME (TME) determination requires the separation of the GE of the excreta of food origin from that of nonfood origin and correcting for this.5 TMEn is TME corrected for protein tissue growth or loss by adding to the excreta energy the energy equivalent of the nitrogen retained or subtracting from it the energy equivilant of the nitrogen lost. However this is relatively small for birds under maintenance conditions.5

The common method to determine ME is by assays in which the test feed is substituted for part of a reference diet or for some ingredient of known ME value.4 An inert, unabsorbed marker such as chromic oxide can simplify the assay by making total quantitative collections of excreta unnecessary. As in digestion studies, the relative concentration of the marker in feed and excreta is used to calculate the amount of excreta derived from a unit of feed consumed.5

The accurate addition and uniform consumption of an index material on a whole seed is not possible thus total feed intake and excreta output must be determined in order to calculate ME. In an ad libitum trial actual feed intake measurement and uncontaminated excreta collection is complicated by feed spillage. Goffin’s Cockatoos are very active birds and beak out their feed from feeders. If wasted feed is mixed with the excreta it will increase experimental error because feed intake and excreta weight are both overestimated.

An alternative experiment which would eliminate these possible errors involves force feeding (FF) the birds a precisely measured amount of liquified feed. No other food would be available to the birds and pure excreta is collected. Parrots exhibit diurnal behaviour and have crops which can store enough food, to be slowly released, until the next feeding. With FF the bird no longer has control over the quantity of food ingested and the level given may not be that promoting energy equilibrium. An increase or decrease in the quantity of food FF may alter digestibility. This will be minimized by FF a quantity of seed kernel approximately equal to the amount ingested by the bird during the ad lib. trial.

Existence metabolism is defined as the energy expenditure of caged birds that maintained a constant body mass over a period of days when they are not undergoing reproduction, molting, migratory unrest, growth, or fat deposition.6 It measures the basal metabolic rate, plus energy for thermoregulation, for specific dynamic action, and for the limited amount of activity permitted by the confines of the cage.6 Existence metabolism for the caged Goffin’s Cockatoos in this study can be calculated from the net amount of food eaten during the ad libitum trial and the determined ME of that feed.

EXPERIMENTAL PROCEDURES

The ME of sunflower seed kernel in adult Goffin’s Cockatoo under maintenance conditions was determined by two different experimental methods, ad libitum and force feeding.

The ad lib. feeding trial lasted five days. To minimize error in this trial feeders were designed to minimize scattering of the feed, wasted feed was collected from under the bird and already hulled seed (kernels only) was fed. To reach the kernels, birds had to stick their heads into the small opening of a gravity feeder and could not easily toss the kernels out. Twice daily, wasted kernel was carefully brushed away from excreta and into a container marked for each bird and filled during the length of the trial. Feed intake over the five days was calculated from feeder weight loss and corrected for spillage of kernels. Daily energy expenditure for each bird can be calculated from the net feed intake and its ME.

The force feeding trial was performed with a syringe and steel feeding tube that was passed down the esophagus directly into the crop. To precisely measure the amount of liquified kernel fed, a syringe loaded with food was tared on a balance before feeding and then weighed after. The kernels were ground up in a coffee grinder and mixed with water to produce 37.5% solids. The birds were tube fed two times a day over three and a half days for a total of seven feedings.

The birds were starved for 36 hours before and after each trial in order to collect only and all excreta produced from feed ingested during the trial. Collection began just before the first feeding and ended 24 hours after the last. The collected excreta were homogenized, dried, finely ground and weighed on a dry matter basis. The birds were individually housed in cages 50cm x 50 cm x 66cm in a climate controlled room maintained at 18°C and 50% relative humidity. The birds were kept under 12 hours light: 12 hours dark lighting regime.

The two trials were run at different times on the same thirty birds. The ME’s resulting from the two methods will be compared and possible areas of error identified. To eliminate bird to bird variation, only paired data from the same bird was used. A paired t test was used to compare ME means of the two groups and the F’ statistic to compare the variances of the two treatments. Although the trials are confounded with time, it is assumed that this has no effect on ME with the adult birds used.

The assay to determine the GE of the feed and excreta is the bomb calorimeter technique. It consists of igniting a weighed sample in an oxygen atmosphere and measuring the amount of heat transmitted to a measured quantity of water. The GE’s are used in the calculation of ME in each bird. The GE of excreta from each bird was determined in duplicate for mean excreta GE. Feed GE was based on the mean of four bombings of sunflower, and for comparison, safflower and peanut kernels.

Many ingredients used in the agriculture feed industry cannot be fed in the pure form as the test animal would stop eating. Parrots will eat sunflower exclusively for many years. This simplifies calculations and increases the precision of the estimate as interactions with other ingredients in a basal test diet will not have to be considered.

Proximate analysis and the GE of three common oilseeds fed to parrots, sunflower, safflower and peanut were determined. A literature review of the amino acid and fatty acid composition of the three oilseeds was done and compared to the estimated requirements (based on broiler requirements) and whole budgie and chicken carcass composition.

RESULTS

The proximate analysis of confectionery sunflower kernel listed in Table 1 indicates its high fat and moderate protein composition. Another oilseed and a legume commonly fed to parrots, safflower and peanut, have a similar composition (Table 1). The GE’s for the three kernels are high as would be expected from their proximate analysis (Table 1).

The metabolizable energy value of sunflower seed kernel in caged Goffin’s Cockatoos was 6.207 ± 0.282 kcal/g when determined in an ad libitum total collection trial and 6.094 ± 0.086 kcal/g when determined by force feeding with total collection (Appendix 1 and 2).

Table 1- 
Proximate analysis of seed kernels or nut meat expressed as per cent (a) and their gross energy value.

Kerne or Nut MeatMoistureCrude
Protein
Crude
Fat
Crude 
Fiber
AshN.F.E (d)GE(e)
kcal/kg
Sunflower(b)4.922.453.83.63.012.37,097
Safflower(c)3.023.659.32.63.28.37,429
Raw Peanut3.629.453.02.42.39.36,829
  1. Mean values of two samples send to separate labs.
  2. Hulled confectionery sunflower as used in the ME trial.
  3. Hulled by hand from seeds found in Topper Bird Ranch Diet, Lexington, N.C.
  4. N.F.E. or nitrogen-free extract, is the difference between 100% and the sum of the percentages of moisture, protein, fat, fiber, and ash. It is considered to represent the carbohydrate other than fiber.
  5. Mean values based on four bomb calorimeteries for each feed.

These mean values for each trial were not significantly different; however, there was significantly greater variation within the ad-lib. trial than when the birds were force fed (Table 2).

Table 2-
Comparison of ME value of sunflower determined by ad libitum and force fed methods

TrialMean ME 
kcal/kg
Std.Dev.Std.errMin. 
kcal/kg
Max. 
kcal/kg
Ad libitum6207 (a)282 (b)655,4986,624
Force fed609486205,8996,208
  1. t statistic is insignificant and the means are thus equal; T = 1.53, d.f.= 36, prob > [t] = 0.1337.
  2. The F’ statistic is highly significant and the variances are thus different; F’= 10.76, d.f.= 18,18 , prob > F’=0.0001.

The mean daily existence metabolism for the Goffin’s under maintenance conditions was 48 Kcal/day/bird or 186 Kcal/day/kg (Appendix 1).

Wasted kernel during the ad lib. trial ranged from 14 g to 201 g with a mean of 58 g per bird.

DISCUSSION

REVIEW OF OILSEED AMINO ACID AND FATTY ACID COMPOSITION

Amino acid requirements are often listed in percentages of the diet however, this way of expressing them makes it difficult to compare the amino acid profiles of diets with different energy and protein levels. Expressing amino acid levels as percentages of the protein rather than the whole diet or feed makes comparisons more meaningful.

The amino acid compositions of the oilseed proteins (Table 3) is based on kernel protein rather than oilseed meal protein which is more commonly found in the literature.7,8,9 Meals are the residue of the seed after extraction of the oil and their amino acid profiles may differ due to the inclusion of hull protein.

Although serine, cystine and tyrosine are not essential amino acids, they are included with the essential amino acids because they can spare a portion of the requirement for glycine, methionine and phenylalanine, respectively.

Table 3- 
Estimated Essential Amino Acid Requirements of Parrots and Composition of three common seed kernel/nut meats (g amino acid/16 g nitrogen).

Essential Amino Acid(a)Estimated
Require(b)
Sunflower
Kernel(c)
Safflower
Kernel(d)
Peanut
Meat(e)
Budgie
Carcass(f
Chicken
Carcass(g)
Arginine6.010.09.411.25.96.8
Glycine
+
Serine
5.09.39.310.410.8
Histidine1.52.82.62.42.24.1
Isoleucine3.54.53.73.3 h 94%3.93.9
Leucine5.97.06.06.66.26.5
Lysine5.03.9 h 78%3.2 h 64%3.2 h 64%7.19.9
Methionine
+
Cystine
3.63.73.2 h2.5 h4.3
Methionine1.91.8 h 95%1.5 h 79%1.2 h 36%2.21.9
Phenylalanine
+
Tyrosine
5.97.47.28.96.86.7
Phenylalanine3.24.74.35.03.93.6
Threonine3.73.83.2 h 86%3.1 h 84% 4.03.4
Valine3.65.25.34.24.84.4
Number of
Limiting Amino Acids
234
  1. Essential for growing poultry.(4)
  2. Based on NRC requirement (4) for Broilers receiving a diet of 20% protein and 3200 kcal ME/kg.
  3. From Robinson RG.(11) and Sastry, MCS, Murray, DR. (17)
  4. From Vanetten et al.(12) and Food and Agriculture. (13)
  5. From Food and Agriculture Organization(13) and Pancholy et al. (14)
  6. From Massey DM, Sellwood EHB, Waterhouse CE.(15)
  7. From Scott ML.(16)
  8. Limiting amino acids and % of requirement supplied when compared to estimated requirements.

However, under certain conditions the requirement for cystine may not be met by synthesis from methionine, especially if the diet is low in both these amino acids. Feather protein contains a higher amount of cystine than other body proteins.10 Thus, during maximum feather growth in a nestling or molting in an adult, the relative requirement for cystine may increase.

Cystine also serves as the precursor of taurine which in chickens and probably parrots as well, is conjugated with cholic acid during the formation of bile.5 Bile formation is induced by fat which is high in oilseed kernels. Thus, these kernels may induce more conversion of methionine to cystine to taurine for formation of taurocholic acid.

Along with incomplete absorbtion, methionine is probably a limiting amino acid in sunflower kernel and isoleucine in peanut meat, during growth or reproduction although their levels are similar to the estimated requirement.

Another factor which may alter specific amino acid requirements in birds being fed oilseed kernel exclusively is that peroxidizing polyunsaturated fats produce aldehydes which may bind lysine.5 The major portion of fat in sunflower and safflower is in the form of the polyunsaturated fatty acid, linoleic (Table 4) and this factor may further exacerbate the already limiting status of lysine within these proteins.

The comparative whole carcass amino acid composition of the chicken to a small parrot, the budgerigar shows a similarity which may allow the use of broiler requirements as estimates of parrot amino acid requirements for growth. Research at UC Davis found the lysine requirement of Cockatiels to be 0.8% and total protein requirement 20% of the diet on a dry matter basis.21,22 This is very similar to the broiler requirements used here as estimates for parrot growth requirements.

Table 4-
Fatty Acid Composition of Sunflower, Safflower and Peanut Oils.

Fatty AcidsSunflower(a)Safflower(b)Peanut(c)
Saturated
Palmitic (16:0)
5 – 75 – 7 8 – 12
Stearic (18:0)2 – 61 – 3 2 – 5
Arachidic (20:0)tr.-.5trace1 – 2
Behenic (22:0)7 – 1trace2 – 3
Unsaturated
Oleic (18:1)
16 – 35 (d) 9 – 20 (d)42 – 54
Linoelic (18:2){e}57 – 7166 – 8020 – 37
Linolenic (18:3)trace-2trace-3trace
  1. Ranges found in the literature.(18,19)
  2. Ranges found in the literature.(18,19)
  3. Ranges found in the literature.(20)
  4. High Oleic (>80%) with low linoelic (<10%) varieties of sunflower and safflower are now available.
  5. Essential fatty acid for poultry.(4)

Based on these estimated requirements for growth in parrots it appears that all three oilseed proteins of sunflower, safflower and peanut are deficient in lysine and methionine/cystine, safflower is also deficient in threonine, and peanut is also deficient in threonine and isoleucine (Table 3). Thus it appears that safflower has a better amino acid profile than peanut and sunflower has a better profile than both safflower and peanut.

METABOLIZABLE ENERGY

Cockatiels fed only safflower seed had an adversion to it with three out of five losing weight and displaying shivering while those fed only sunflower gained 65% more weight in 60 days than those fed safflower.23

The greater variation in ME during the ad lib. trial was probably due to the large amount of feed wastage the birds did. The birds on average wasted 58.3 g which is much more than the 38.5 g that they ate over the same period. It appears that the natural hulling behaviour of the birds is strong as they were trying to hull the already hulled kernels.

The AME of sunflower kernel is high when compared to that of formulated diets commonly used in the poultry feed industry.4 This should be expected with the high fat composition of the kernel. High ME’s should also be expected for safflower and peanut kernel whose nutrient composition is similar to that of sunflower seed.

The predicted basal metabolic rate (BMR) based on the formula for nonpasserine birds in kcal/day/kg body weight (BMR = 91.0 b.w.0.729)24 for a 0.261 kg bird is 83.8 kcal/day/kg. Comparing this to the existence metabolism of 186 kcal/day/kg calculated from the ad lib. trial data (Table 1) it appears that in these birds existence metabolism is about 2.2 times the predicted BMR. The thermal neutral zone (TNZ) of Green-cheeked Amazons (Amazona viridigenalis) was found to be from 26.5°C to at least 35.0°C.25 Both Green-cheeked Amazons and Goffin’s Cockatoo come from similar tropical environments and probably have similar TNZ. The housing temperature in this study was 18°C, below the lower critical temperature found for the amazon. Therefore the cockatoos in this study probably expended energy to maintain body temperature.

Bird number 15 had an existence metabolism below even the BMR predicted for its weight, 70 vs. 84 kcal/day/kg (Appendix 1). While it was not checked this bird must have lost weight over the period of the trial.

The ME value of sunflower kernel is high (and is expected to be high for safflower and peanut too) and cage bird owners whose birds are obese should be advised to limit the amount of oilseeds that they give to their birds.

The Department of Avian Sciences, University of California Davis, has published several papers on the nutritional value of sunflower seed kernel and its proximate composition compared to safflower seed kernel.23,26,27 However conflicting nutrient analysis is often found in the popular literature usually because it includes the fibrous hulls which Psittacines do not eat.28,29,30 One booklet does not differentiate the requirements for growth and maintenance, lists inaccurate sunflower seed amino acid levels and incorrectly concludes that sunflower seed contains low quality protein.31 Thus confusion, as to which seed is more nutritious, continues with many “experts” saying that safflower is more nutritious based on the falsely assumed lower fat content, or exaggerated unsaturated fatty acid differences.32,33 Birds may in fact be avoiding the safflower because of its bitter taste and cathartic effect and therefore eating a greater variety of food items.34,35

Authors of articles for popular magazines should use figures of nutrient levels derived from laboratory analysis or refereed journals and not quote from agriculture feed tables that may include the fiberous hull in the analysis. The oilseed nutrient values listed here should help those who are involved in advising pet bird owners and aviculturists on seed mixes and prepared pelleted diets.

Acknowledgments

Rolf C. Hagen, Inc. funded the research, provided the birds and their custom made cages and the University of Guelph provided the facilities to perform the bomb calorimeter and house the birds.

References

  1. Anonymous: A nationwide survey of pet owners. Amer. Pet Prod. Man. Assoc., 1988.
  2. Wan PJ et al: Characteristics of sunflower seed and meal. Cereal Chem. 56(4):352-355
  3. Miller MR, Reinecke KJ: Proper expression of metabolizable energy in avian energetics. Condor 86:396-400, 1984.
  4. National Research Council: Nutrient requirements of poultry. 8th ed. Washington DC, National Academy Press, 1984.
  5. Scott ML, Nesheim MC, Young RJ: Nutrition of the chicken. 3rd ed. Ithaca NY, M. L. Scott and Associates, 1982.
  6. Kendeigh SC, Dol’nik VR, Gavrilov: Avian energetics. In Pinowski J, Kendeigh SC (eds): Granivorous Birds in Ecosystems. London, Cambridge Uni. Press, 1977, pp 127-157.
  7. Tkachuk R, Irvine GN: Amino Acid compositions of cerals and oilseed meals. Cereal Chem. 46:206-218, 1969.
  8. Sosulski F, Fleming SE: Chemical, functional, and nutritional properties of sunflower protein products. J. Am. Oil Chem. Soc. 54:100A-104A, 1977.
  9. Sosulski FW, Sarwar G: Amino acid composition of oilseed meals and protein isolates. J. Inst. Can. Technol. Aliment. 6(1):1-5, 1973.
  10. Deschutter A, Leeson S: Feather growth and development. World’s Poultry Sci. 42(3):259-267, 1986.
  11. Robinson RG: Amino acid and elemental composition of sunflower and pumpkin seeds. Agron. Jour. 67:541-544, 1975.
  12. VanEtten CH et al: Amino acid composition of safflower kernels, kernel protein, and hulls and solubility of kernel nitrogen. Agri. Food Chem. 11(2):137-139, 1963.
  13. Food and Agriculture Organization: Amino acid contents of foods and biological data on proteins. FAO Nutr. Stud. No. 24, FAO, Rome, 1970. 1970
  14. Pancholy, SK, Deshpande, AS, Krall, S: Amino acids, oil and protein content of some selected peanut cultivars. Proc. Amer. Peanut Res. Educ. Assoc. 10:30-37, 1978.
  15. Massey DM, Sellwood EHB, Waterhouse, CE: The amino acid composition of budgerigar diet, tissue and carcase. Vet. Rec. 72(15):283-287, 1960.
  16. Scott ML: Nutrition in reproduction – direct effects and predictive functions. In: Breeding Biology of Birds. Washington DC, Nat. Acad. Sci., 1973, pp 46-73.
  17. Sastry, MCS, Murray, DR: The tryptophan content of extractable seed proteins from cultivated legumes, sunflower and Acacia. J. Sci. Food Agric. 37: 535-538, 1986.
  18. Waliszewski K: Fatty acid composition of different oils and their soapstocks. Nutri. Rep. Inter. 35(1):87-91, 1987.
  19. Weiss WA: Oilseed crops. London, Longman, 1983.
  20. Sreenivasan B: Component fatty acids and composition of some oils and fats. J Amer. Oil Chem. Soc. 45:259-265, 1968.
  21. Grau CR, Roudybush TE: Lysine requirement of cockatiel chicks. Amer. Fed. Avi. Watchbird, Dec/Jan:12-14, 1986
  22. Roudybush TE, Grau CR: Food and water interrelations and the protein requirement for growth of an altricial bird, the Cockatiel. J. Nutr. 116:552-559, 1986.
  23. McDaniel LD, Roudybush T: Cockatiel experiments. 31st West. Poul. Dis. Conf. pp 157-158, 1982.
  24. Aschoff J, Pohl H: Rhythmic variations in energy metabolism. Fed. Proc. 29(4):1541-1552, 1970.
  25. Bucher TL: Ventilation and oxygen consumption in Amazona viridigenalis. J Comp. Physiol. B 155:269-276, 1985.
  26. Grau, CR: Sunflower seeds for Psittacines. Exotic Bird Report 1:1-6.
  27. Roudybush, T: Papaverine absent from sunflower seeds. Exotic Bird Report 5:1-2.
  28. Tollefson, CI: Nutrition. In: Diseases of Cage and Aviary Birds, 2nd ed. Ed. ML Petrak, Lea & Febiger, Philadelphia pp 220-249, 1982.
  29. McCluggage, D, Irmiger, RO: Basic avian nutrition. National Cockatiel Society 4(4):32-33, 1987.
  30. Coyle, PG: Understanding the Life of Birds. Summit Pub, pp 304, 1987.
  31. Murphy, J: The Complete Guide to Parrot Nutrition, copyright Author, pp 40, 1984.
  32. Feare, D: Tips from Top Experts (quotes McCluggage, D). Parrot World 5(2):23, 1987.
  33. Clutterbuck, D: Safflower-What’s that (quotes Brown, R). Australian Aviculture 41(8):209, 1987.
  34. Palter, R, Lundin, RE: A bitter principle of safflower; Matairesinol Monoglucoside. Phytochem. 9:2407-2409, 1970.
  35. Palter, R, Lundin, RE, Haddon, WF: A cathartic lignan glycoside isolated from Carthamus tinctorus. Phytochem. 11:2871-2874, 1972.

APPENDIX 1 –
Existence metabolism of caged Goffin’s Cockatoo based on the metbolizable energy of sunflower kernel as determined in an ad libitum trial over five days with a total collection of the excreta.

Sunflower KernelExistence MetabolismBird Wt.Existence Metabolism
ME (e)
cal./g.
cal./day/
bird (f)
g.Kcal/day/kg
6,37857,782275210
6,49265,569275238
6,47843,274257168
6,37846,052289159
6,13445,149304149
6,48559,792242247
6,07940,123248162
6,30551,573239216
5,70148,685286170
6,37057,326241238
6,11442,428267159
5,99630,339266114
6,25753,062294180
5,49818,14526170
6,62480,019246325
6,19144,947228197
5,97838,620270143
6,04525,391233109
6,43668,737244282
6,207261
48,264186
Bird ID
Number
Kernels IngestedTotal ExcretaSunflower KernelExistence MetabolismBird Wt.Existence Metabolism
n=19Net(a) g.Total GE(b) calD.M. basis, g.GE (C) cal/g.Total GE (d) cal.ME (e)
cal./g.
cal./day/bird (f)g. Kcal/day/kg
 145.3 321,4859.8 3,32032,5736,378 57,782275 210
 2 50.5 358,388 9.43,26730,5436,49265,569275238
 333.4237,0335.93,49020,6626,47843,274257168
 4 36.1256,194 7.83,32925,9336,378 46,052289159
636.8261,16210.73,30435,4156,13445,149304149
746.1327,1628.33,41428,2036,48559,792242247
833.0234,19410.13,33133,5806,07940,123248162
940.9290,2599.53,42432,3926,30551,573239216
1042.7303,03318.23,27059,6065,70148,685286170
1145.0319,3569.63,41232,7256,37057,326241238
1234.7246,25910.03,40834,1196,11442,428267159
1325.3179,5498.43,32027,8525,99630,339266114
1442.4300,90410.83,31135,5966,25753,062294180
1516.5117,0977.73,41226,3745,49818,14526170
1660.4 428,6478.33,43128,5506,62480,019246325
1736.3257,6149.33,53632,8816,19144,947228197
1832.3229,22710.63,39636,1285,97838,620270143
1921.0149,0336.43,46122,0786,04525,391233109
2253.4378,96910.73,31035,2866,43668,737244282
means38.5273,4519.53,37632,1316,207261 —
x / day7.754,6901.96,42648,264 186

Bird ID
Number
n=19

1


Kernels Ingested
Net(a) g. 45.3
Total GE(b) cal 321,485


Total Excreta
D.M. basis, g. 9.8
GE (C) cal/g. 3,320
Total GE (d) cal. 32,573


Sunflower Kernel
ME (e) cal./g. 6,378


Existence Metabolism
cal./day/bird (f) 57,782


Bird Wt.
g. 275


Existence Metabolism
Kcal/day/kg 210

Bird ID
Number
n=19

2


Kernels Ingested
Net(a) g. 50.5
Total GE(b) cal 358,388


Total Excreta
D.M. basis, g. 9.4
GE (C) cal/g. 3,267
Total GE (d) cal. 30,543


Sunflower Kernel
ME (e) cal./g. 6,492


Existence Metabolism
cal./day/bird (f) 65,569


Bird Wt.
g. 275


Existence Metabolism
Kcal/day/kg 238

Bird ID
Number
n=19

3


Kernels Ingested
Net(a) g. 33.4
Total GE(b) cal 237,033


Total Excreta
D.M. basis, g. 5.9
GE (C) cal/g. 3,490
Total GE (d) cal. 20,662


Sunflower Kernel
ME (e) cal./g. 6,478


Existence Metabolism
cal./day/bird (f) 43,274


Bird Wt.
g. 257


Existence Metabolism
Kcal/day/kg 168

Bird ID
Number
n=19

4


Kernels Ingested
Net(a) g. 36.1
Total GE(b) cal 256,194


Total Excreta
D.M. basis, g. 7.8
GE (C) cal/g. 3,329
Total GE (d) cal. 25,933


Sunflower Kernel
ME (e) cal./g. 6,378


Existence Metabolism
cal./day/bird (f) 46,052


Bird Wt.
g. 289


Existence Metabolism
Kcal/day/kg 159

Bird ID
Number
n=19

6


Kernels Ingested
Net(a) g. 36.8
Total GE(b) cal 261,162


Total Excreta
D.M. basis, g. 10.7
GE (C) cal/g. 3,304
Total GE (d) cal. 35,415


Sunflower Kernel
ME (e) cal./g. 6,134


Existence Metabolism
cal./day/bird (f) 45,149


Bird Wt.
g. 304


Existence Metabolism
Kcal/day/kg 149

Bird ID
Number
n=19

7


Kernels Ingested
Net(a) g. 46.1
Total GE(b) cal 327,162


Total Excreta
D.M. basis, g. 8.3
GE (C) cal/g. 3,414
Total GE (d) cal. 28,203


Sunflower Kernel
ME (e) cal./g. 6,485


Existence Metabolism
cal./day/bird (f) 59,792


Bird Wt.
g. 242


Existence Metabolism
Kcal/day/kg 247

Bird ID
Number
n=19

8


Kernels Ingested
Net(a) g. 33.0
Total GE(b) cal 234,194


Total Excreta
D.M. basis, g. 10.1
GE (C) cal/g. 3,331
Total GE (d) cal. 33,580


Sunflower Kernel
ME (e) cal./g. 6,079


Existence Metabolism
cal./day/bird (f) 40,123


Bird Wt.
g. 248


Existence Metabolism
Kcal/day/kg 162

Bird ID
Number
n=19

9


Kernels Ingested
Net(a) g. 40.9
Total GE(b) cal 290,259


Total Excreta
D.M. basis, g. 9.5
GE (C) cal/g. 3,424
Total GE (d) cal. 32,392


Sunflower Kernel
ME (e) cal./g. 6,305


Existence Metabolism
cal./day/bird (f) 51,573


Bird Wt.
g. 239


Existence Metabolism
Kcal/day/kg 216

Bird ID
Number
n=19

10


Kernels Ingested
Net(a) g. 42.7
Total GE(b) cal 303,033


Total Excreta
D.M. basis, g. 18.2
GE (C) cal/g. 3,270
Total GE (d) cal. 59,606


Sunflower Kernel
ME (e) cal./g. 5,701


Existence Metabolism
cal./day/bird (f) 48,685


Bird Wt.
g. 286


Existence Metabolism
Kcal/day/kg 170

Bird ID
Number
n=19

11


Kernels Ingested
Net(a) g. 45.0
Total GE(b) cal 319,356


Total Excreta
D.M. basis, g. 9.6
GE (C) cal/g. 3,412
Total GE (d) cal. 32,725


Sunflower Kernel
ME (e) cal./g. 6,370


Existence Metabolism
cal./day/bird (f) 57,326


Bird Wt.
g. 241


Existence Metabolism
Kcal/day/kg 238

Bird ID
Number
n=19

12


Kernels Ingested
Net(a) g. 34.7
Total GE(b) cal 246,259


Total Excreta
D.M. basis, g. 10.0
GE (C) cal/g. 3,408
Total GE (d) cal. 34,119


Sunflower Kernel
ME (e) cal./g. 6,114


Existence Metabolism
cal./day/bird (f) 42,428


Bird Wt.
g. 267


Existence Metabolism
Kcal/day/kg 159

Bird ID
Number
n=19

13


Kernels Ingested
Net(a) g. 25.3
Total GE(b) cal 179,549


Total Excreta
D.M. basis, g. 8.4
GE (C) cal/g. 3,320
Total GE (d) cal. 27,852


Sunflower Kernel
ME (e) cal./g. 5,996


Existence Metabolism
cal./day/bird (f) 30,339


Bird Wt.
g. 266


Existence Metabolism
Kcal/day/kg 114

Bird ID
Number
n=19

14


Kernels Ingested
Net(a) g. 42.4
Total GE(b) cal 300,904


Total Excreta
D.M. basis, g. 10.8
GE (C) cal/g. 3,311
Total GE (d) cal. 35,596


Sunflower Kernel
ME (e) cal./g. 6,257


Existence Metabolism
cal./day/bird (f) 53,062


Bird Wt.
g. 294


Existence Metabolism
Kcal/day/kg 180

Bird ID
Number
n=19

15


Kernels Ingested
Net(a) g. 16.5
Total GE(b) cal 117,097


Total Excreta
D.M. basis, g. 7.7
GE (C) cal/g. 3,412
Total GE (d) cal. 26,374


Sunflower Kernel
ME (e) cal./g. 5,498


Existence Metabolism
cal./day/bird (f) 18,145


Bird Wt.
g. 261


Existence Metabolism
Kcal/day/kg 70

Bird ID
Number
n=19

16


Kernels Ingested
Net(a) g. 60.4
Total GE(b) cal 428,647


Total Excreta
D.M. basis, g. 8.3
GE (C) cal/g. 3,431
Total GE (d) cal. 28,550


Sunflower Kernel
ME (e) cal./g. 6,624


Existence Metabolism
cal./day/bird (f) 80,019


Bird Wt.
g. 246


Existence Metabolism
Kcal/day/kg 325

Bird ID
Number
n=19

17


Kernels Ingested
Net(a) g. 36.3
Total GE(b) cal 257,614


Total Excreta
D.M. basis, g. 9.3
GE (C) cal/g. 3,536
Total GE (d) cal. 32,881


Sunflower Kernel
ME (e) cal./g. 6,191


Existence Metabolism
cal./day/bird (f) 44,947


Bird Wt.
g. 228


Existence Metabolism
Kcal/day/kg 197

Bird ID
Number
n=19

18


Kernels Ingested
Net(a) g. 32.3
Total GE(b) cal 229,227


Total Excreta
D.M. basis, g. 10.6
GE (C) cal/g. 3,396
Total GE (d) cal. 36,128


Sunflower Kernel
ME (e) cal./g. 5,978


Existence Metabolism
cal./day/bird (f) 38,620


Bird Wt.
g. 270


Existence Metabolism
Kcal/day/kg 143

Bird ID
Number
n=19

19


Kernels Ingested
Net(a) g. 21.0
Total GE(b) cal 149,033


Total Excreta
D.M. basis, g. 6.4
GE (C) cal/g. 3,461
Total GE (d) cal. 22,078


Sunflower Kernel
ME (e) cal./g. 6,0452


Existence Metabolism
cal./day/bird (f) 5,391


Bird Wt.
g. 233


Existence Metabolism
Kcal/day/kg 109

Bird ID
Number
n=19

22


Kernels Ingested
Net(a) g. 53.4
Total GE(b) cal 378,969


Total Excreta
D.M. basis, g. 10.7
GE (C) cal/g. 3,310
Total GE (d) cal. 35,286


Sunflower Kernel
ME (e) cal./g. 6,436


Existence Metabolism
cal./day/bird (f) 68,737


Bird Wt.
g. 244


Existence Metabolism
Kcal/day/kg 282

Bird ID
Number
n=19

means


Kernels Ingested
Net(a) g. 38.5
Total GE(b) cal 273,451


Total Excreta
D.M. basis, g. 9.5
GE (C) cal/g. 3,376
Total GE (d) cal. 32,131


Sunflower Kernel
ME (e) cal./g. 6,207


Existence Metabolism
cal./day/bird (f)


Bird Wt.
g. 261


Existence Metabolism
Kcal/day/kg

Bird ID
Number
n=19

x / day


Kernels Ingested
Net(a) g. 7.7
Total GE(b) cal 54,690


Total Excreta
D.M. basis, g. 1.9
GE (C) cal/g.
Total GE (d) cal. 6,426


Sunflower Kernel
ME (e) cal./g.


Existence Metabolism
cal./day/bird (f) 48,264


Bird Wt.
g.


Existence Metabolism
Kcal/day/kg 186

  1. Feeder wt. at start – feeder wt. at finish – wasted kernel.
  2. Weight kernel intake x GE of kernel, 7096.8 cal/g.
  3. Mean of two bomb calorimeteries for each excreta sample.
  4. Total weight of excreta x GE of excreta.
  5. {Total GE ingested – total GE excreted}/ net intake.
  6. Includes the energy of basal metabolic rate, heat increment, cage activity and thermoregulation. Equals net feed intake per day x ME of feed.

APPENDIX 2 –
Metabolizable energy of force-fed sunflower kernel with a total collection of excreta over three and half days.

Bird ID
Number
Kernels IngestedTotal ExcretaSunflower Kernel
n=19Net(a) g.Total GE(b) calD.M. basis, g.GE (C) cal/g.Total GE (d) cal.ME (e)
cal./g.
 1 30.9219 ,2918.63,50230,084 6,123
 229.8 211,4859.13,49131,8366,028
 327.3193,7438.23,47828,4176,056
 426.9190,9047.23,41924,6176,182
629.7210,7758.83,45230,5196,069
731.0220,0018.53,64531,0186,096
825.1178,1307.63,39025,6486,075
930.0212,9048.23,33427,3686,185
1030.4215,7437.83,50727,4226,195
1126.6188,7758.93,57231,8605,899
1228.6202,9688.13,47528,2526,109
1326.4187,3567.03,34123,4566,208
1431.0220,0019.63,37332,2476,057
1525.6181,6787.73,61827,8976,007
1630.2214,3238.03,49527,9946,170
1729.5209,3569.33,71834,5795,925
1825.4180,2597.93,33326,3006,061
1928.0198,7107.33,47625,2036,197
2232.1227,8079.03,43530,8136,137
means28.7 203,379 8.3 3,477 28,712 6,094 

Bird ID
Number

n=19

1


Kernels Ingested
Net(a) g. 30.9

Total GE(b) cal 219,291


Total Excreta
D.M. basis, g. 8.6

GE (C) cal/g. 3,502
Total GE (d) cal. 30,084


Sunflower Kernel
ME (e) cal./g. 6,123

Bird ID
Number

n=19

2


Kernels Ingested
Net(a) g. 29.8

Total GE(b) cal 211,485


Total Excreta
D.M. basis, g. 9.1

GE (C) cal/g. 3,491
Total GE (d) cal. 31,836


Sunflower Kernel
ME (e) cal./g. 6,028

Bird ID
Number

n=19

3


Kernels Ingested
Net(a) g. 27.3

Total GE(b) cal 193,743


Total Excreta
D.M. basis, g. 8.2

GE (C) cal/g. 3,478
Total GE (d) cal. 28,417


Sunflower Kernel
ME (e) cal./g. 6,056

Bird ID
Number

n=19

4


Kernels Ingested
Net(a) g. 26.9

Total GE(b) cal 190,904


Total Excreta
D.M. basis, g. 7.2

GE (C) cal/g. 3,419
Total GE (d) cal. 24,617


Sunflower Kernel
ME (e) cal./g. 6,182

Bird ID
Number

n=19

6


Kernels Ingested
Net(a) g. 29.7

Total GE(b) cal 210,775


Total Excreta
D.M. basis, g. 8.8

GE (C) cal/g. 3,452
Total GE (d) cal. 30,519


Sunflower Kernel
ME (e) cal./g. 6,069

Bird ID
Number

n=19

7


Kernels Ingested
Net(a) g. 31.0

Total GE(b) cal 220,001


Total Excreta
D.M. basis, g. 8.5

GE (C) cal/g. 3,645
Total GE (d) cal. 31,018


Sunflower Kernel
ME (e) cal./g. 6,096

Bird ID
Number

n=19

8


Kernels Ingested
Net(a) g. 25.1

Total GE(b) cal 178,130


Total Excreta
D.M. basis, g. 7.6

GE (C) cal/g. 3,390
Total GE (d) cal. 25,648


Sunflower Kernel
ME (e) cal./g. 6,075

Bird ID
Number

n=19

9


Kernels Ingested
Net(a) g. 30.0

Total GE(b) cal 212,904


Total Excreta
D.M. basis, g. 8.2

GE (C) cal/g. 3,334
Total GE (d) cal. 27,368


Sunflower Kernel
ME (e) cal./g. 6,185

Bird ID
Number

n=19

10


Kernels Ingested
Net(a) g. 30.4

Total GE(b) cal 215,743


Total Excreta
D.M. basis, g. 7.8

GE (C) cal/g. 3,507
Total GE (d) cal. 27,422


Sunflower Kernel
ME (e) cal./g. 6,195

Bird ID
Number

n=19

11


Kernels Ingested
Net(a) g. 26.6

Total GE(b) cal 188,775


Total Excreta
D.M. basis, g. 8.9

GE (C) cal/g. 3,572
Total GE (d) cal. 31,860


Sunflower Kernel
ME (e) cal./g. 5,899

Bird ID
Number

n=19

12


Kernels Ingested
Net(a) g. 28.6

Total GE(b) cal 202,968


Total Excreta
D.M. basis, g. 8.1

GE (C) cal/g. 3,475
Total GE (d) cal. 28,252


Sunflower Kernel
ME (e) cal./g. 6,109

Bird ID
Number

n=19

13


Kernels Ingested
Net(a) g. 26.4

Total GE(b) cal 187,356


Total Excreta
D.M. basis, g. 7.0

GE (C) cal/g. 3,341
Total GE (d) cal. 23,456


Sunflower Kernel
ME (e) cal./g. 6,208

Bird ID
Number

n=19

14


Kernels Ingested
Net(a) g. 31.0

Total GE(b) cal 220,001


Total Excreta
D.M. basis, g. 9.6

GE (C) cal/g. 3,373
Total GE (d) cal. 32,247


Sunflower Kernel
ME (e) cal./g. 6,057

Bird ID
Number

n=19

15


Kernels Ingested
Net(a) g. 25.6

Total GE(b) cal 181,678


Total Excreta
D.M. basis, g. 7.7

GE (C) cal/g. 3,618
Total GE (d) cal. 27,897


Sunflower Kernel
ME (e) cal./g. 6,007

Bird ID
Number

n=19

16


Kernels Ingested
Net(a) g. 30.2

Total GE(b) cal 214,323


Total Excreta
D.M. basis, g. 8.0

GE (C) cal/g. 3,495
Total GE (d) cal. 27,994


Sunflower Kernel
ME (e) cal./g. 6,170

Bird ID
Number

n=19

17


Kernels Ingested
Net(a) g. 29.5

Total GE(b) cal 209,356


Total Excreta
D.M. basis, g. 9.3

GE (C) cal/g. 3,718
Total GE (d) cal. 34,579


Sunflower Kernel
ME (e) cal./g. 5,925

Bird ID
Number

n=19

18


Kernels Ingested
Net(a) g. 25.4

Total GE(b) cal 180,259


Total Excreta
D.M. basis, g. 7.9

GE (C) cal/g. 3,333
Total GE (d) cal. 26,300


Sunflower Kernel
ME (e) cal./g. 6,061

Bird ID
Number

n=19

19


Kernels Ingested
Net(a) g. 28.0

Total GE(b) cal 198,710


Total Excreta
D.M. basis, g. 7.3

GE (C) cal/g. 3,476
Total GE (d) cal. 25,203


Sunflower Kernel
ME (e) cal./g. 6,197

Bird ID
Number

n=19

22


Kernels Ingested
Net(a) g. 32.1

Total GE(b) cal 227,807


Total Excreta
D.M. basis, g. 9.0

GE (C) cal/g. 3,435
Total GE (d) cal. 30,813


Sunflower Kernel
ME (e) cal./g. 6,137

Bird ID
Number

n=19

means


Kernels Ingested
Net(a) g. 28.7

Total GE(b) cal 203,379


Total Excreta
D.M. basis, g. 8.3

GE (C) cal/g. 3,477
Total GE (d) cal. 28,712


Sunflower Kernel
ME (e) cal./g. 6,094

  1.  Intubated twice a day for three and half days.
  2. Weight kernel intake x GE of kernel, 7096.8 cal/g.
  3. Mean of two bomb calorimeteries for each excreta sample.
  4. Total weight of excreta x GE of excreta.
  5. {Total GE ingested – total GE excreted}/ net intake.

By Mark Hagen, M.Ag.
Director of Research

Discover the Research Aviary

Explore the history of HARI, including how Mark Hagen founded the organization and helped it take flight. Delve deeper into the research that takes place at the aviary, and how HARI has become a leader in studying parrot care and breeding.