Isabelle D. Kalmar 1 * Guy Werquin 2 Geert P.J. Janssens 1. Merelbeke; 2 Versele-Laga Ltd., 9800 Deinze, Belgium. Introduction

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1 MINERAL INTAKE IN AFRICAN GREY PARROTS (PSITTACUS E ERITHACUS) FED A SEED MIXTURE OR EXTRUDED PELLETS AD LIBITUM, AND ITS EFFECTS ON EXCRETA CHARACTERISTICS. Isbelle D. Klmr 1 * Guy Werquin 2 Geert P.J. Jnssens 1 1 Lbortory of Animl Nutrition, Fculty of Veterinry Medicine, Ghent University, 9820 Merelbeke; 2 Versele-Lg Ltd., 9800 Deinze, Belgium Introduction Whole-seed diets encompss severl nutritionl constrints when fed to prrots. First, the edible prt of seeds is strongly imblnced in clcium to phosphorus (C:P) rtio nd is deficient in severl essentil mino cids nd vitmins (Hrrison, 1998). Next, seed mixtures re high in energy nd ft content, which is further incresed by the typicl feeding behvior of prrots. Dt of Werquin et l. (2005) showed n verge of 16.4 ± 0.9 MJ ME/kg nd 19.7 ± 6.3 % ft in commercil seed mixtures (n=30); the edible, dehulled frction contining 22.4 ± 2.9 MJ ME/kg nd 31.7 ± 13.1 % ft. In comprison, diets for chickens for fttening usully contin 12 to 13 MJ ME/kg nd considerbly less thn 10% ft (NRC, 1994). Moreover, when provided multi-component seed diet, prrots disply strong tendency to select minly oilseeds such s sunflower seeds or pumpkin seeds, which results in distinct nutrient profile between offered diet nd ctully ingested portion (Klmr et l., ccepted). However, in spite of profound nutritionl constrints, cptive prrots re still commonly fed seed mixtures. A high prevlence of mlnutrition relted diseses in cptive prrots is thus not surprising. Pellet diets, in contrst to seed mixtures, offer the dvntge tht they cn be formulted to best meet nutritionl guidelines; moreover its content is not bised by selective feeding. Then gin, nutritive vlue is not the only issue in dietry strtegies. Feed cost, for instnce, is usully higher in pellet diets compred to seed mixtures. Another importnt constrint ginst feeding pellets insted of seeds is supposed reduction in time spent by feed intke, resulting in boredom, overfeeding nd behviorl disturbnces. However, Wolf et l. (2002) demonstrted similr time budgets for feeding behvior when prrots re fed pellets compred to seed mixtures. Another drwbck ginst pellet diets is the initil reluctnce of prrots ginst new food items. Nevertheless, severl conversion strtegies hve been demonstrted to be sfe nd successful (Ghysels, 1997). Excret chrcteristics lso constitute considertion in the evlution of diet. Excret firmness is sometimes lower when fed pellets compred to seed mixtures. This cn be due to n increse in excret moisture content or by lower wter binding cpcity. A generlly higher sodium content in pellet diets might possibly increse excret moisture content, s demonstrted in lying hens (Smith et l., 2000); wheres rtificil prticle size reduction in the mnufcturing of pellets might negtively influence excret wter holding cpcity (Klmr et l., 2007). Excret cidity is lso trit of importnce, s low intestinl ph cn contribute to protection ginst cid-intolernt pthogens (Nughton nd Jensen, 2001). The present tril ws imed to evlute the effect of selective feeding nd seed dehusking on minerl intke nd dietry ction nion difference (DCAD) in prrots fed seed mixture d

2 libitum. The effect of this dietry minerl intke nd DCAD on excret chrcteristics such s cidity, moisture content nd consistency is compred with two pellet diets differing in protein content. Dietry protein hs been shown to ffect excret cidity in broiler chickens (Nmroud et l., 2008). Mterils Eight dult, 3-yer old Africn grey prrots (Psittcus e erithcus), four mles nd four femles, with n verge weight of 490 ± 8 g were individully housed in wire metbolism cges. The bottom of the cge consisted of removble, metl drwer, which fcilitted totl collection of feed refusls. Ambient temperture nd reltive humidity rnged between 19.5 nd 21.1 C, nd 53.8 nd 62.2 % respectively. The photoperiod ws determined by outdoor sunlight. Efforts were mde to relieve boredom by providing crylic bird toys, which were chnged dily, nd by timer controlled rdio inside the niml house. The experimentl design ws 3x3 cross-over tril with 3 nine-dy feeding periods in which 3 diets were tested: seed mixture (Prestige prrot premium (R) ) nd two extruded pellet diets, P15 (Nutribird P15 (R) with moderte protein content (15 %)) nd P19 (Nutribird P19 (R) with high protein content (19 %)) (Versele Lg Ltd). Food nd wter were provided d libitum nd were refreshed dily. Ech of the three feeding periods consisted of 4 dys of dpttion, mesurement of excret ph nd consistency t dy 5, followed by 4-dy period in which verge dily food nd wter intke were mesured nd totl excret output collected. Food nd wter were provided d libitum nd were refreshed dily. The birds were well cquinted to ll test diets prior to the tril. Mesurement of excret ph ws done on 3 fresh droppings per bird, per diet, using digitl glss electrode probe with n ccurcy of 0.1. Excret consistency index (ECI) ws ssessed on 5 fresh excrements per bird, per diet by rtio of surfce re to weight, s described by Klmr et l. (2007). With this method, lower ECI-vlue represents higher firmness of droppings. Excret output per bird, per period ws lyophilized nd dried to determine dry mtter content. The totl mount of seed reminders ws pooled per bird nd homogenized. Minerl nlysis ws performed on subsmples of offered diets nd seed reminders. These smples were shed t 500 C nd subjected to cid digestion in HCL followed by ICP nlysis of sodium (N), potssium (K), clcium (C), mgnesium (Mg), phosphorus (P), sulphur (S), zinc (Zn), mngnese (Mn), nd copper (Cu). Chlorine (Cl) ws determined potentiometriclly using n ion selective electrode. Minerl (X) concentrtion of ingested frction nd DCAD were clculted s follows: [X] ingested frction = ([X] offered mixture * offered mixture (g)) - ([X] reminder * reminder (g)) (offered mixture (g) - reminder (g)) DCAD (meq/kg) = N + K + C + Mg + P + Cl + S mg/kg * vlence In which minerls re expressed s moleculr weight As guidelines on minerl content re usully expressed on cloric bsis, proximte nlysis ws performed on bove mentioned food smples ccording to stndrd methods of the Assocition of Officil Anlyticl Chemists (AOAC, 1984). Anlysed nutrient composition

3 nd clculted ME content of test diets, including the consumed frction of the seed diet, re presented in tble 1. Results Tble 1: Nutrient content nd energy density of test diets nd consumed frction of the offered seed mixture (s fed). P15 P19 Seed Mixture pellets pellets offered consumed Crude Protein Ether Extrct Crude Fiber Crude Ash N-Free Extrct ± ± ± ± ± 2.9 ME (*) ± 151 * ME = 18 CP + 39 EE + 17 NFE (Schoemker nd Beynen, 2001) with: ME: metbolizble energy (kj/100 g); CP: crude protein ; NFE: N-free extrct : EE: ether extrct Dily wter nd food intke were similr between P15 nd P19 pellets, but were significntly nd considerbly lower when fed the seed diet. The ph of excret did not differ between pellet diets but ws considerbly lower when fed seeds. The ECI shows tht feeding P19 pellets led to firmest droppings. Dry mtter content of droppings ws significntly higher when fed seeds compred to pellets (tble 2). Tble 2: Dily intke nd excret chrcteristics in Africn grey prrots fed either extruded pellets with moderte (P15) or high (P19) protein content or seed diet d libitum (N=8). P15 pellets P19 pellets Seed mixture SEM Intke Wter (ml/d) b 3 < Food (g/d) b 1 < Excret chrcteristics Moisture 74.3 b 74.4 b ECI b 28.6 b ph b 0.2 < 0.001,b different superscripts within row indicte significnt difference t P < P DCAD in P15 pellets, offered seed mixture nd P19 pellets ws 477 meq/kg, 486 meq/kg nd 526 meq/kg, respectively. However, DCAD in the ingested frction of the offered seed mixture ws only 121 ± 97 meq/kg. Sodium content ws only bove recommendtions in P15 pellets, wheres C nd Mg requirements were covered in ll test diets nd none of the diets contined sufficient Cl ccording to vilble guidelines. The ingested frction of the seed diet ws lso deficient in K nd P content. Next, C:P rtio ws sufficient in both pellet diets nd offered seed mixture, but feeding behvior deteriorted C:P rtio when fed the multi-component seed diet. Finlly, both pellet diets were sufficiently high in ll tested trce elements, but the offered mixture ws too low in Mn nd Zn. The ingested frction of the seed diet ws lso fr below the recommended guideline of Cu (tble 3).

4 Tble 3: Minerl nd trce minerl concentrtion in offered nd ingested diets. Pellets Seed Mixture P15 P19 Offered Consumed Requirement (,b) Minerls (g/mj ME) Sodium (N) ± Potssium (K) ± Clcium (C) ± Mgnesium (Mg) ± Phosphorus (P) ± Chlorine (Cl) ± Trce minerls ( mg/mj ME) Sulfur (S) ± Zinc (Zn) ± Mngnese (Mn) ± Iron (Fe) Copper (Cu) ± C:P ± 0.60 min 1.50 b Bvelr nd Beynen (2003); b Wolf (2002) Discussion To dte, species-specific scientific dt on minerl requirements re still scrce, hence bove mentioned guidelines re tenttive. However, suboptiml C supply nd C:P rtio when fed seed-bsed diets is well-known cuse of impired skeletl minerlistion nd is consistent with clinicl presenttion in prctice (Wolf et l., 1998). The profoundly low Cu content in ingested seed frction is lso likely to be of significnce for prrot helth, s Cu is n essentil compound in severl enzymes nd is importnt in sustining erythropoïesis (Tollefson, 1982). Absence of effects of dietry protein content on excret cidity re not consistent to results of Nmroud et l. (2008), who demonstrted effects of dietry protein content on excret cidity in broilers. In the current tril, the vstly lower DCAD in ingested seed frction compred to both pellet diets, hs likely contributed to the lower excret ph when fed seeds. The low dietry N level in the ingested frction of the seed mixture coincided with lower dropping moisture content thn when fed either pellet diets, which is in ccordnce with dt in lying hens (Smith et l,. 2000). Yet, similr moisture content between both pellet diets concomitnt with much firmer droppings when fed P19 pellets compred to P15 pellets, points to differentil wter binding cpcity of droppings. Literture Cited AOAC Officil Methods of Anlysis of the Assocition of Officil Anlyticl Chemists. 13. Assocition of Officil Anlyticl Chemists, Arlington, VA. Bvelr, F.J. nd A.C. Beynen Beoordeling vn commerciële ppegienvoeders. Tijdschr. Diergeneesk. 23:

5 Ghysels P Trnsferring birds to pellet feeding: successful methods for different species. Proceedings of the 1st ISPBN, October 3-4, 1997, Hnnover, p. 98. Hrrison, G.J Twenty yers of progress in pet bird nutrition. J. Am. Vet. Med. Assoc. 212: Klmr, I.D., Veys, A.C., Geeroms, B., Reinschmidt, M., Wugh, D., Werquin, G., Jnssens, G.P.J. Effect of segregtion nd impct of specific feeding behviour nd dditionl fruit on voluntry nutrient intke nd energy intke in yellow-shouldered mzons (Amzon brbdensis) when fed multi-component seed diet d libitum. J. Anim. Physiol. Anim. Nutr. (Accepted) Klmr, I.D., Werquin, G. nd G.P.J. Jnssens Apprent digestibility nd excret qulity in Africn grey prrots fed two pelleted diets differing in prticle size. J. Anim. Physiol. Anim. Nutr. 91: Nmroud, N.F., Shivzd, M. nd M. Zghri Effects of fortifying low crude protein diet with crystlline mino cids on performnce, blood mmoni level, nd excret chrcteristics of broiler chicks. Poult Sci 87: Ntionl Reserch Council (NRC) Nutrient requirements of poultry. 9 th edn. Ntionl Acdemy of Sciences, Wshington, DC, 155 Pp. Nughton, P. J. nd B.B. Jensen. 2001: A biorector system to study survivl of Slmonell typhimurium in pig gut content. Berl. Munch. Tierrzt. Wochenschr. 114,1-4. Tollefson, C.I Nutrition. Pp In Diseses of cge nd viry birds (Petrk, L.M., ed.), Le & Febiger, Phyldelphi, PA. Schoemker, N. J. nd A.C. Beynen De smenstelling vn commerciële beovoeders met bijzondere ndcht voor het ijzergehlte. Tijschr. Diergeneesk. 126, Smith, A., Rose, S.P., Wells, R.G. nd V. Pirgozliev The effect of chnging the excret moisture in cged lying hens on the excret nd microbil contmintion of their egg shells. Br. Poult. Sci. 41, Werquin G., De Cock K. nd P. Ghysels Comprison of the nutrient nlysis nd energy density of 30 commercil seed mixtures (in toto nd dehulled) with 27 commercil pellets for prrots. J. Anim. Physiol. Anim. Nutr. 89: Wolf, P Nutrition of Prrots. Proceedings of the 5 th IPC, September 18-21, 2002, Puerto de l Cruz, Pp Wolf, P, Grubohm, S.nd J. Kmphues Experimentl dt on feeding extruded diets in prrots. In: Proceedings of the JNS, August 21-25, 2002, Antwerp, p Wolf, P., Byer, G., Wendler, C. nd J. Kmhues Minerl deficiencies in pet birds. J. Anim. Physiol. Anim. Nutr. 80: