Application of the beta-hydroxy-beta-methylbutyric (HMB) acid in broiler chicken feeding

Roczniki Naukowe Polskiego Towarzystwa Zootechnicznego, t. 6 (2010), nr l Application of the beta-hydroxy-beta-methylbutyric (HMB) acid in broiler chicken feeding Maria Wiąz, Michał Bratos, Sebastian Kaczmarek, Andrzej Rutkowski University of Life Sciences in Poznań, Faculty of Animai Breeding and Biology, Department of Animai Nutrition and Feed Management, ul. Wołyńska 33,60-637 Poznań The aim of the performed investigations was to ascertain the usefulness of leucine derivative - ~-hydroxy-~-methylbutiric (HMB) acid in broiler chicken nutrition and to determine the level of this acid in feed. The experimental material comprised 360 Ross 308!ine cockerels which were divided into three experirnental groups of 120 birds each, The eontent of the HMB acid incorporated into diets amounted to: 0.05% in group II and to 0.15% in group III, whereas the birds from group I were fed the diets without HMB acid supplementation. Throughout the duration of the trial, body weight gains and feed consumption were controlled. At the termination of the experiment, 10 birds were randomly selected from each nutritional group, slaughtered and directly after slaughtering, chyme ph was measured in five segments of the gastrointestinal tract foliowed by simp!ified slaughter analysis. It was found that the app!ication of the HMB acid improved body weight gains of experimental birds, feed conversion ratios, increased proportions of the breast muscle in the carcass and European Index of Productivity (EIP) of broilers. Additionally, it was also observed that the HMB acid supplementation exerted a positive impact on broiler survivability and ph of the individual sections of the gastrointestinal tract. KEY WORDS: ~-hydroxy-~-methylbutyric (HMB) acid I broiler chickens I production parameters I dressing percentage I ph of the gastrointestinal tract Beta-hydroxy-beta-methylbutyric (HMB) acid, a leucine derivative, was discovered in 1994 by a team headed by Steve Nissen [6] who demonstrated favourable effects of this acid on the development and activity of the broiler chicken immune system. In in vitro experiments, it was found that the above compound induces macrophage proliferation and stimulates phagocytosis processes. Peterson et al. [8], Peterson et al. [9] and Fuller et al. [2] fed broiler chickens HMB acid in amounts ranging from 0.0 l to 0.10% of the diet and found that it exerted a stimulating impact on cellular and humoral resistance which can be responsible for animai increased survivability. The effect of the ~-hydroxy-~-methylbutyrate on fish celi ular and humorał resistance was investigated in a number of experiments by Siwicki et al. [11, 12, 13]. They demonstrated a significant 101

influence of this acid on the stimulation of cellular and humoral resistance and, consequently, on decreased sensitivity to diseases and reduction of the mortality index. Nissen et al. [5, 6] checked if HBM affects musc1e proteins' transformations. Depending on proportions of the l3-hydroxy-l3-methylbutiric acid, chicken death rates we re dernonstrated to decline. Tako et al. [15] administered HMB to chicken embryos on the l7 th day of incubation by direct injection into the amniotic cavity and demonstrated its favourabie effect on the development of intestinal villi and body weight gains in comparison with the controi group. Foye et al. [l] also injected HMB into the amniotic cavity of turkey embryos and observed an increase of glycogen eontent in the liver and musc1es as well as significantly higher body weight in comparison with the birds from the eon troi group without HMB administration. Materiał and methods The experimental materia l included 360 one-day-old Ross 308 cockerels. The trial lasted for 5 weeks which were divided into two nutritional periods: Starter - the first two weeks and Grower - the remaining 3 weeks. The prepared diets were isoprotein and isoenergetic. The feed mixtures composition was balanced with the assistance of the RecPasz 4.56 optimisation program based on.feed Recommendations" [10] and is shown in Table 1. Chieks had a continuous access to water. Birds were randomly clivided into three experimental groups and kept on litter in 8-bird boxes. Each nutritional group consisted of 15 replications (boxes), i.e. 120 birds in one group. All groups were fed identical diets but with different levels of supplementation with the l3-hydroxy-l3-methylbutyric (HMB) acid. The proportions of the HMB acid in feed ranged from 0.05% in group II to 0.15% in group III. Group I was the controi and the birds in this group were fed diets without the addition of the HMB acid. Table 2 shows the division of birds into groups and levels of the HMB acid supplementation. Throughout the experiment, body weight gains and feed consumption were measured weekly. At the termination of the experiment, 10 birds were randomly selected from each nutritional group, slaughtered and, directly after slaughtering, chyme ph was measured in five segments of the gastrointestinal tract: the crop, gizzard, small intestine, caecum and the final intestine. This was followed by simplified slaughter analysis which inc1uded: plucking, evisceration, cutting off the neck, and cutting the carcass along the back and sternum into halves. Next, the right half of the carcass was weighed, leaf fat was separated and the breast muscle was cut out and the dressing percentage of individual carcass components as well as the percentage proportion of the breast musc1e in the carcass were ca1culated in relation to the half-carcass mass. Carcass dressing percentage was ca1culated in relation to the chicken body weight. All the obtained results were subjected to statistical elaboration using for this purpose SAS statistical package [14]. 102

Table 1 - Tabela 1 Composition of Starter and Grower diets and their nutritive value Skład mieszanek starter i grower oraz ich wartość pokarmowa Components Starter Grower Komponenty (kgll 00 kg feed) (kgll 00 kg feed) (kglido kg paszy) (kg/l 00 kg paszy) Ground maize grain 25.22 27.00 Śrutowane ziarno kukurydzy Ground wheat grain 32.00 37.99 Śrutowane ziarno pszenicy Soybean meal 46% 34.00 26.50 Poekstrakcyjna śruta sojowa 46% Soybean oil 5.00 4.80 Olej sojowy Calcium phosphate 1.27 l.l5 Fosforan jedno wapniowy Chalk 0.50 0.60 Kreda pastewna Sodium carbonate 0.10 Węglan sodu L-Iysine 78% 0.27 0.25 L-lizyna 78% DL-methionine 98% 0.25 0.22 DL-metionina 98% L-threonine 98% 0.09 0.13 L-treonina 98% NaCI 0.30 0.36 Premix SIG 1.00 1.00 Metabolisable energy (kcal/kg) 3058.81 3109.80 Energia metaboliczna (kcal/kg) Metabolisable energy (MJ/kg) 12.81 13.02 Energia metaboliczna (Ml/kg) Total protein (%) 22.18 19.59 Bialko ogólne (%) Total fibre (%) 2.90 2.81 Wlókno ogólne (%) Lysine (%) 1.30 l.l I Lizyna (%) Methionine (%) 0.56 0.50 Metionina (%) Threonine (%) 0.86 0.79 Treonina (%) Total Ca (%) 0.95 093 Ca ogólny (%) Available P (%) 0.45 0.41 P przyswajalny (%) Total Na (%) 0.18 0.16 Na ogólny (%) NaCI(%) 0.35 0.40 Results and discussion During the period of starter feeding (Tab. 3), depending on the level of HMB supplementation, statistically significant differences (P~0.05) were recorded in body weight gains of the experimental chickens. In the case of birds from group III (0.15% HMB), body weight gains were statistically significantly higher (P~0.05) than in group II (0.05% HMB). During the period of feeding with the Grawer mixture, group I (control) and II (0.05% HMB) differed from each other significantly (P~0.05) in favour 103

Table 2 - Tabela 2 Experimental design and levels of additional HMB acid in feed Schemat grup doświadczalnych i poziom dodawanego kwasu HMB w paszy Group Grupa I Il III HMB supplementation (giloo kg feed) Dodatek HMB (glioo kg paszy) o 78 234 Percentage Procentowy proportion of HMB o 0.05 0.15 udzial HMB of group II, whereas in the case of group III, despite lack of statistically significant differences, body weight gains of the birds from this group were higher than in group L All in all, in the entire period of the trial, chicken body weight gains in both experimental groups (at different levels of HMB supplementation) were higher in comparison with the control and the results differed statistically significantly (P~O.05) in favour of experimental groups, contrary to the results reported by Nissen et al. [6]. Feed consumption in both nutritional periods (Tab. 3) was similar and no significant differences were recorded between groups. Generally speaking, feed consumption per l kg body weight gai n (FeR) was more favourable in experimental groups (II and III) than in the control but no statistically significant differences between groups were observed. Table 3 - Tabela 3 Body weight gains, feed consumption (in kg) and FCR Przyrosty masy ciała, spożycie paszy (kg) i zużycie paszylkg przyrostu masy ciała (FCR) Specification Group - Grupa Wyszczególnienie II III Incrernents in starter period (kg) 0.295"h 0.291 h 0.313' Przyrosty w okresie starter (kg) Increments in grawer period (kg) 1.523 b 1.614" 1.594 01 ' Przyrosty w okresie grower (kg) Total increments (kg) 1.81S" 1.905' 1.90S' Przyrosty ogólem (kg) Starter consumption (kg) 0.451 0.445 0.442 Spożycie paszy starter (kg) Grower consumption (kg) 2.273 2.346 2.319 Spożycie paszy grawer (kg) Total feed consumption (kg) 2.724 2.791 2.761 Spożycie paszy ogólem (kg) FCR starter 1.544,b 1.537'h 1.434 b FCR grower 1.496"b 1.454 b 1.455 b Total FCR 1.502,h 1.466" 1.448 b FCR ogólem a, b, c - differences statistically significant at PS::O.05- różnice statystycznie istotne przy PS::O,05 104

Beneficial impact of the ~-hydroxy-~-methylbutyric acid on bird body weight was reported by Tako et al. [15], Dni et al. [16, 17] and Foye et al. [1]. However, in the above experiments, the acid was administered directly into the amniotic cavity in the 17 th day of incubation and stimulated the development of intestinal villi instead of inhibiting the break up of muscle proteins. The anticatabolic action of the ~-hydroxy-~- -methylbutyric acid suggested in literature [3, 7] could affect the final weight of the breast muscle increasing the dressing percentage of birds and the percentage proportion of individual parts of muscles in the carcass. The performed experiment corroborated the hypothesis that the inclusion in the feed of the ~-hydroxy-~-methylbutyric acid affects slaughter parameters of broiler chickens (Tab. 4). HMB acid supplementation at the level of 0.15% (group III) increased statistically significantly (P:::;0.05) the mean proportion of the breast muscle in the carcass. In addition, the inclusion of HMB in the feed also affected the eontent of leaf fat. Group II fed diets containing 0.05% HMB was characterised by statistically significantly lower share of leaf fat in the carcass. Feed supplementation with HMB acid was found to improve bird slaughter parameters as their carcasses were characterised by higher proportions of the breast muscle and lower fattening. These results appear to contradiet those reported by Nissen et al. [6]. American researchers investigated the influence of the beta-hydroxy-beta-methylbutyric acid administered to chickens at various concentrations with or without addition of coccidiostatics and antibiotics but fai led to demonstrate any impact of the examined acid on slaughter parameters. The addition of the HMB acid exerted a statistically significant (P:::;0.05) effect on the EIP (Tab. 4); experimental groups were characterised by higher EIP than the control group. Table 4 - Tabela 4 Results of slaughter analysis and EIP Wyniki analizy rzeźnej oraz EWW Specification Wyszczególnienie Carcass weight (g) Masa tuszki (g) Weight of thoracic muscle (g) Masa mięśnia piersiowego (g) Leaf fat weight (g) Masa tłuszczu sadelkowego (g) Dressing percentage Wydajność rzeźna (%) EIP EWW Groups - GruPY II III Addition of acid - Dodatek kwasu O 0.05 0.15 1196 1171 1219 171.2 b 173.1 h 184.1" 20.1" 17.2 b 20.1' 61.8 62.2 61.3 342 b 379" 375' a, b - differences statistically significant at P~O.05 - różnice statystycznie istotne przy ~0,05 105

The addition of the HMB acid improved chicken survivability (Tab. 5); in the case of group II, the proportion of dead birds was 0%, while for group III - 2.5%. The highest proportion of dead birds (3.37%) was recorded in the control group without the inclusion of the HMB acid. Our results are in keeping with those reported by Peterson et al. [8], Fuller et al. [2], Nissen et al. [4,6]. Table 5 - Tabela 5 Deaths ofbroilers (%) Upadki kurcząt (%) Group Grupa II III Deaths (%) Upadki (%) 3.33 o 2.5 Positive effects of the inclusion of the HMB acid on the gizzard chyme ph were recorded in experimental groups (II and III) in which the determined ph was lower than in the contral graup and the results differed statistically significantly (P~0.05) (Tab. 6). Lower ph chyme of the final intestine was determined in graup III (0.15% HMB) and the obtained result differed statistically significantly (P~0.05) from that recorded in the contral group. By reducing chyme ph of the gastrointestinal tract, it is possible to exert a stabilising influence on the composition of the positive microbial flora and, in doing so, to reduce the unfavourable impact of raw materials of strong buffering properties. The advantageous influence of the HMB acid on the composition of the bacterial flora of the gastraintestinal tract could be treated as an alternative for antibiotics. Organie acids as well as their salts inhibit the development of fungi and, by doing so, restrict possibilities of development of mycotoxins. Table 6 - Tabela 6 Chyme ph of 5 segments of gastrointestinal tract Kwasowość (ph) treści pokarmowej pięciu odcinków przewodu pokarmowego Specification Group - Grupa Wyszczególnienie II III Crop 4.748" 4.837"b 4.733 h Wole Gizzard 3.621" 3.256 b 3.215 b Mielec Smali intestine 5.801'" 5.858"" 5.724 b Jelito cienkie Caecum 6.445' 6.708 b 6.546"b Jelito ślepe Final intestine 6.378' 6.442' 6.064 b Jelito końcowe a, b - differences statistically significant at P:<;O.05- różnice statystycznie istotne przy P:<;O,05 106

Recapitulating the results of the performed investigations, it can be said that they corroborated the usefulness of the beta-hydroxy-beta-rnethylbutyric acid in broiler chicken nutrition. The examined acid exerted a positive influence on rearing (body weight gains and ElF) as well as slaughter (weight of breast muscle and leaf fat) parameters of broiler chickens. Moreover, feed supplementation with the HMB acid improved broiler chicken survivability and reduced ph of same segments of the gastrointestinal tract which may exert a stabilising impact on the composition of bacterial flora. It can be recommended that the optimal level of supplementation of broiler chicken diets with the HMB acid is 0.15%. REFERENCES l. FOYE O.T., UNI Z., FERKET P.R., 2006 - Effect of in ovo feeding egg white protein, beta-hydroxy-beta-methylbutyrate and carbohydrates on glycogen status and neonatal growth of turkeys. Poultry Science 85, 1185-1192. 2. FULLER J.e. Jr., NISSEN S., 1994 - Decreasing male broiler mortality by feeding the laucine catabolite beta-hydroxy-beta-methylbutyrate. Poultry Science 73, 93-95. 3. GALLAGHER P.M., CARRITHERS JA, GODART M.P., SCHULZE K.E., TRAPPE S.W., 2000 - Beta-hydroxy-beta-methylbutyrate ingestion. Part I: Effects on strength and fat free mass. Med. Sci. Sports Exerc. 32,2109-2115. 4. NISSEN S.L., ABUMRAD N.N., 1997 - Nutritional role of the leucine metabolite beta-hydroxy-beta-rnethylbutyrate (HMB). J. Nut. Biochem. 8, 300-311. 5. NISSEN S.L., PAPET L, OSTASZEWSKI P., GLOMOT F., OBLED c, FAURE M., BAYLE G., ARNAL M., GRIZARD J., 1997 - The effect of high dose of beta - hydroxy-beta-rnethylbutyrate on protein metabolism in growing lambs. Br. J. Nutr. 77, 885-896. 6. NISSEN S.L., FULLER J.e. Jr., SELL J., FERKET P.R., RIVES D.Y, 1994 - The effect of beta-hydroxy-beta-methylbutyrate on growth, mortality and carcass qualities of broiler chickens. Poult. Sci. 73, 137-155. 7. OSTASZEWSKI P., KOSTlUK S., BALASINSKA B, JANK M., PAPET L, GLOMOT F., 2000 - The leucine metabolite beta-hydroxy-beta-rnethylbutyrate (HMB) modifies protein turnover in muscles of the laboratory rats and domestic chickens in vitro. J. AnilIl. Physiol. Anim. Nutr. 84, 1-8. 8. PETERSON A.L., QUERSHI MA, FERKET P.R., FULLER J.e. Jr., 1999 - Enhancement of cellular and humorai immunity in young broilers by the dietary supplementation of beta- -hydroxy-beta-methylbutyrate. Immunopharmacol. Immunotoxicol: 21,307-330. 9. PETERSON A.L., QUERSHI MA, FERKET P.R., FULLER J.e. Jr., 1999 - In vitro exposure with beta-hydroxy-beta-methylbutyrate enhances chicken macrophage growth and function. Vet. Immunol. Imm unopatlt ol. 67, 67-78. 10. Praca zbiorowa (red. S. Smulikowska, A. Rutkowski), 2005 - Zalecenia żywieniowe i wartość pokarmowa pasz. NOImy żywienia drobiu. Instytut Fizjologii i Żywienia Zwierząt PAN, Jabłonna. 11. SIWICKI A.K., FULLER J.e. Jr., NISSEN S., OSTASZEWSKI P., STUDNICKA M., 2000 - In vitro effects of beta-hydroxy-beta-rnethylbutyrate (HMB) on celi mediated immunity in fish. Vet. Immunol. Immunopathol. 76, 191-197. 12. SIWICKI A.K., FULLER J.e. Jr., NISSEN S., OSTASZEWSKI P., MORAND M., GORYCZ- KO K., KAZUN K., GŁOMBSKI E., 2003 - Influence of feeding the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) on the non-specific cellular and humoral defense mechanisms of rainbow trout (Oncorhynchus mykiss). J. Appl. Ichtyol. 19, 44-48. 107

108 Maria Wiąz, Michał Bratos, Sebastian Kaczmarek, Andrzej Rutkowski Zastosowanie kwasu beta-hydroksy-beta-metylomasłowego (HMB) w żywieniu kurcząt rzeźnych Streszczenie Przeprowadzono badania, których celem było stwierdzenie przydatności pochodnej leucyny - kwasu ~-hydroksy-~-metylomasłowego (HMB) w żywieniu kurcząt brojlerów oraz określenie poziomu tego kwasu w paszy. Materiał doświadczalny stanowiło 360 kogutków linii Ross 308. Ptaki zostały podzielone na trzy grupy doświadczalne, po 120 sztuk w każdej. Udział kwasu HMB wynosił 0,05% w grupie II oraz 0,15% w grupie III, natomiast grupa I stanowiła grupę kontrolną bez dodatku kwasu HMB. W czasie trwania doświadczenia kontrolowano przyrosty masy ciała i spożycie paszy. Na zakończenie eksperymentu wybrano losowo po 10 ptaków z każdej grupy żywieniowej, ubito je i bezpośrednio po uboju zmierzono ph treści pokarmowej w pięciu odcinkach przewodu pokarmowego, a następnie przeprowadzono uproszczoną analizę rzeźną. Stwierdzono, że zastosowanie kwasu HMB poprawiło przyrosty masy ciała kurcząt, współczynniki wykorzystania paszy, zwiększyło udział mięśni piersiowych w tuszce oraz europejski współczynnik wydajności brojlera (EWW). Zaobserwowano również pozytywny wpływ dodatku HMB na przeżywalność ptaków i ph poszczególnych odcinków przewodu pokarmowego.