Short Communication Effects of fattening length, feather colour and sex on some traits in native Turkish geese. II. Carcass traits

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1 Arch.Geflügelk., 73 (1). S , 2009, ISSN Verlag Eugen Ulmer, Stuttgart Short Communication Effects of fattening length, feather colour and sex on some traits in native Turkish geese. II. Carcass traits Einfluss der Mastdauer, der Gefiederfarbe und des Geschlechts auf einige Leistungsmerkmale bei Türkischen Landgänsen. II. Schlachtkörpermerkmale M. Saatcı 1, M. Tilki 2, I. Kaya 3 and T. Kırmızıbayrak 2 Manuskript eingegangen am 8. November 2007, angenommen am 3. Mai 2008 Introduction Although goose breeding is not a common livestock practise in Turkey, it is an important rural activity around Kars city. Geographical specifications of the area with numerous water resources give an advantage for the mentioned livestock activity. Goose breeding in the region is an old tradition with the family traditional rearing methods. Additionally, eating goose meat is a part of tradition in the region, even several customs have been established on preserving, preparing and eating goose. These characteristics make the region the most geese populated area in Turkey. Therefore, the region has been chosen to make this research on native Turkish geese. Although, there are not any certain differences among the geese reared in the region, some differences can be mentioned according to feather colour and origin as pointed out by SAATCI et al. (2005). Meat is the most desirable product of geese but breeders do not show any attempt to increase meat production and quality. All geese in the region are reared under the range condition. Therefore, their carcass-meat product is restricted with the standards of pasture. It is possibile that these geese may reach better carcass quality when are reared under intensive condition. There are very few studies on rearing native Turkish geese under intensive condition but none of them was run in Kars as the largest goose keeping area in Turkey (ÇELEBı, 1999; ISGUZAR and TESTIK, 1999; TıLKı and İNAL, 2004). Quality meat from goose is obtained from 8 10 weeks period and this type of goose is called broiler in the intensive system. High feed conversion efficiency and high meat yield are vital in broiler goose but these characteristics are affected by age, breed, sex, diet and duration of fattening period (HROUZ, 1988; BUTLER et al., 1991; GRUNDER et al., 1991). Moreover, it is crucial to know overall growth patterns and carcass traits to develop a plan for a suitable fattening scheme (FORTIN et al., 1983; GRUNDER et al., 1991). Due to the stated reasons, present study was conducted to define slaughter characteristics and carcass traits of native Turkish geese fattened under intensive condition. Besides, effects of fattening length, sex and feather colour on the mentioned traits were studied. Fattening performance of Turkish native geese was also evaluated. Material and Methods Animal Material In total, 145 Turkish native geese at the age of 10 (Group I) and 12 (Group II) weeks were used in the experiment. Geese are presented in Table 1 according to fattening period, feather colour and sex. Although fattening period and feather colour were determined easily, sex of the animals was determined after slaughter by checking genital organs (ovaries or testicles). Birds were divided into four subgroups according to their feather colour in each fattening period and they were fed under intensive condition according to recommendations of NRC (1994). Slaughter and Carcass Geese were slaughtered at the age of 10 or 12 weeks according to fattening period. Prior to slaughter, birds were fasted for hours. Each goose with a certain wing tag was weighted and bled, and dry plucked by hand. After plucking and eviscerating, carcasses were stored 24 hours at +4 C and were dissected according to Jones (10). Additionally, carcass parts (leg, breast, back, wing and neck) were assessed with and without skin. After the remove of head and foot, whole carcass was weighted. Abdominal fat was gathered from the abdominal membrane, and around gizzard and liver. Mesenterial fat was only collected from mesenteries. Obtained data were recorded for each bird individually. 1Mehmet Akif Ersoy University, Veterinary Medicine Faculty, Dept. of Animal Science, Burdur, Turkey 2 Kafkas University, Veterinary Medicine Faculty, Dept. of Animal Science, Kars Turkey 3Kafkas University, Veterinary Medicine Faculty, Dept. of Animal Nutrition, Kars Turkey Statistical Analyses A General Linear Model was used for the evaluation of both slaughter and carcass traits. Fattening groups, feather colour and sex were included in the model as fixed effects.

2 62 Saatci et al.: Effects on geese carcass Table 1. Distribution of geese to treatments Verteilung der Gänse auf die Behandlungen 10 Week fattening (Group I) Male Female Total Black White Piebald Yellow Total Week fattening (Group II) Black White Piebald Yellow Total General Total Differences between the groups were defined with Tukey test. Minitab statistical package was used for analyses. The follwing model was used for analyses of slaughter and carcass traits. Y ijkl = µ + a i + b j + c k +e ijkl Y ijk = i. Fattening group, j. Feather colour, k. Sex µ = Mean, a i = Age group (i= 1 2; 10 and 12 weeks), bj = Feather Colour group (j= 1 4; Black, White, Piebald, Yellow), c k = Sex (k= 1 2; Male, Female), = Error. e ijkl Results Slaughter and carcass traits of geese are presented according to fattening length, feather colour and sex in Table 2. Significant influence of fattening length was observed for some traits. For example, in terms of head, carcass, breast, back, total skin and internal fats geese in Group II produced heavier weights than those in Group I (P < 0.05). But, interestingly only liver weight of Group I was significantly heavier than in Group II (P < 0.05). Feather colour significantly influenced weights of carcass, head, foot, gizzard, wing, leg and internal fats (P < 0.05). In general, yellow and black geese were heavier while the lightest one was Piebalds. Sex also had a significant effect on traits with male geese heavier than females in the entire evaluated carcass components (P < 0.05). Percentages of body parts were calculated from cold carcass weight and results are shown in Table 3. Percentages of heart, liver, breast, back and total internal fat in relation to cold carcass weight were significant between Group I and Group II (P < 0.05). While heart, liver and gizzard percentage were higher in Group I, breast, back and total internal fat percentages was higher in Group II. Discussion The study added to current knowledge on native Turkish geese by definition of slaughter and carcass characteristics reared under intensive conditions. Influences of fattening period, feather colour and sex on slaughter and carcass characteristics were determined. The results gave a possibility to evaluate carcass composition of native Turkish geese in terms of broiler capacity. Although, no difference between Groups I and II could be observed for slaughter weight, significant differences between the two groups were found for carcass weights and carcass parts. This significant difference between carcass weights was not observed in dressing percentage. Defined carcass weights for Group I (2270 g) and Group II (2397 g) were fairly lower than those values reported for Embden, Italian, Pilgrim and Hungarian geese, but similar to Chinese geese (FORTIN et al., 1983; GRUNDER et al., 1991; KIRCHGEßNER et al., 1997). Generally, dressing percentage of the studied geese was between 66% and 67%, these values were in agreement with (66 68%) ÇELEBı (1999) and PUCHAJDA and WEIS (1988), but lower than the values (70 73%) reported by TıLKı and İNAL (2004) and HROUZ et al. (1988). The extension of the fattening period by two weeks increased extra mesenterial and abdominal fats, and skin weight in geese of group II. Geese of Group II showed also significantly greater values for breast and back, both for weights and percents (Table 2 and 3). This situation may indicate that growing of wing and leg stopped earlier but breast and back parts continued their growing until 12 th week. Fat accumulation in abdomen, mesenteries and skin was greater in Group II compared with Group I, it means that fat deposition continued until the end of week 12. This continuing increase in both breast and fat was in agreement with other studies (GRUNDER et al., 1991; CAVE et al., 1994). The observed increase in back part from 10 to 12 weeks which mainly constitutes of bone shows that bone development is still in progress. Contrary to previously mentioned parts, weight and percent of liver significantly decreased from 10 week (76.06 g; 2.22%) to 12 week (66.44 g; 1.88%) in accordance to to previous findings of authors (13 15) for days old Embden and 6 12 weeks old Turkish geese, respectively. Slaughter weights of geese in feather colour groups showed a significant difference. This difference resulted from the lowest weight of Piebalds. The low slaughter weight in Piebald geese was reflected in weights of foot, gizzard, wing, leg, total internal fat and percents of head and total internal fat. Black and yellow geese reached higher weights than other two groups for slaughter weight and most carcass parts. Especially, yellow geese had the highest weights for head, foot, gizzard, back, breast and the highest percents for head and liver (Table 2 3). But, these high values were not statistically different from other groups. The same situation was observed for black geese. Black geese were non-significantly heavier than others in terms of slaughter, carcass, wing and leg weights. Sex significantly influenced actual weights of all evaluated parts. Males were relatively heavier than females but this influence mostly disappeared when percents were calculated. Significant sex effect was only detected for neck and wing percents as stated by CAVE et al. (1994). Furthermore, females showed a higher dressing percentage and percents of liver, leg, etc. (Table 3). According to obtained results, intensive fattening in native Turkish geese after 10 weeks did not provide any notable advantages for carcass parts. Breast was the only valuable part to increase its weight until 12 weeks. Therefore, birds might be slaughtered in tenth week to reduce fattening expenses. No distinct differences in carcass parts according to feather colour could be observed but Black and Yellow geese showed more noteworthy carcass traits than the others. Although, neither distinct breed nor

3 Saatci et al.: Effects on geese carcass 63 Table 2a. Effects of fattening period, feather colour and sex on carcass weight and carcass traits I Einfluss der Mastdauer, der Gefiederfarbe und des Geschlechts auf das Schlachtkörpergewicht und die Schlachtkörpermerkmale I Traits (g) Slaughter weight Blood Head Foot Liver Hot carcass Cold carcass Fattening periods - - * - * * * 10 Weeks ± ± ± ± ± ± ± Weeks ± ± ± ± ± ± ±38.74 Colour * - * * Black ±84.05 a ± ±2.93 ab ±3.03 ab 73.76± ± ±56.83 White ±86.32 ab ± ±3.01 b ±3.11 ab 74.45± ± ±58.36 Piebald ±88.64 b ± ±3.09 b ±3.19 b 63.83± ± ±59.93 Yellow ±86.89 a ± ±3.03 a ±3.13 a 72.95± ± ±58.75 Sex * * * * * * * Male ± ± ± ± ± ± ±41.25 Female ± ± ± ± ± ± ±41.25 Traits (g) Neck S+ Neck S- Wing S+ Wing S- Leg S+ Leg S- Total skin Fattening periods * 10 Weeks ± ± ± ± ± ± ± Weeks ± ± ± ± ± ± ±14.44 Colour - - * * * * - Black ± ± ±09.84 a ±09.80 a ±16.00 a ±13.54 a ±21.19 White ± ± ±10.10 ab ±10.07 ab 70.71±16.43 ab ±13.90 ab ±21.76 Piebald ± ± ±10.37 b ±10.34 b ±16.87 b ±14.28 b ±22.34 Yellow ± ± ±10.17 a ±10.13 a ±16.54 ab ±14.00 ab ±21.90 Sex * * * * * * * Male ± ± ± ± ± ± ±15.38 Female ± ± ± ± ± ± ± = (P > 0.05), * = P < 0.05, (+) with skin, (-) without skin, (a, b) differences between the groups having different superscripts are significant (P<0.05).

4 64 Saatci et al.: Effects on geese carcass Table 2b. Effects of fattening period, feather colour and sex on carcass weight and carcass traits II Einfluss der Mastdauer, der Gefiederfarbe und des Geschlechts auf das Schlachtkörpergewicht und die Schlachtkörpermerkmale II Traits (g) Chest S+ Chest S- Back S+ Back S- Mesenterial fat Abdominal fat Total internal fat Fattening periods * * * * * * * 10 Weeks ± ± ± ± ± ± ± Weeks ± ± ± ± ± ± ±7.00 Colour * - * * Black ±15.22 a ± ± ±13.85 ab 53.53± ±5.48 ab ±10.27 ab White ±15.63 a ± ± ±14.22 b 68.43± ±5.63 a ±10.54 a Piebald ±16.05 b ± ± ±14.60 b 46.64± ±5.78 b ±10.83 b Yellow ±15.73 a ± ± ±14.32 a 55.37± ±5.66 ab ±10.61 ab Sex * * * * * * * Male ± ± ± ± ± ± ±7.45 Female ± ± ± ± ± ± ±7.56 variety differences among Turkish geese could be detected observed small differences indicate the necessity for further studies. Native Turkish geese can not be compared with other European native geese in terms of carcass traits and fattening capacity but due to their smaller carcass size they can be served as oven ready types. Further studies with different diets and various fattening lengths have to be conducted to describe the characteristics of native Turkish geese in more detail. Acknowledgment This work has been financially supported by TÜBİTAK (The Scientific and Technical Research Council of Turkey) and authors gratefully acknowledge TÜBİTAK for the valuable help in every stage of the study. Summary The study was conducted to define slaughter yield and carcass composition of native Turkish geese which were fattened under intensive condition. The study was also intended to determine the effects of fattening length, sex and feather colour on the investigated traits. For these aims, in total 145 native Turkish geese at the age of 10 and 12 weeks were slaughtered and carcass characteristics were determined. Feather colour affected significantly weights of carcass, head, foot, gizzard, wing, leg and internal fats (P < 0.05). In generall, yellow and black geese were heavier while Piebalds were the lightest ones. Whereas, liver and gizzard percentage were higher in 10 weeks old geese, breast, back and total internal fat percentages were higher in 12 weeks old ones. Native Turkish geese did not provide any noteworthy advantages for the yields of carcass parts after 10 weeks. Breast was the only valuable part which increased until 12 weeks. Therefore, it can be recommended that birds kept under intensive conditions should be slaughtered in tenth week or should be allowed to pasture feeding in 9 th 10 th weeks to reduce fattening expenses. Key words Native Turkish geese, fattening length, sex, feather colour, carcass traits Zusammenfassung Einfluss der Mastdauer, der Gefiederfarbe und des Geschlechts auf einige Leistungsmerkmale bei Türkischen Landgänsen. II. Schlachtkörpermerkmale Die Studie wurde durchgeführt, um die Schlachtausbeute und die Schlachtkörperzusammensetzung von verschiedenen türkischen Landgansschlägen unter intensiven Haltungsbedingungen zu bestimmen. Ferner sollte der Einfluss von der Mastdauer, der Gefiederfarbe und des Geschlechts untersucht werden. Hierzu wurden insgesamt 145 Türkische Landgänse im Alter von 10 bzw. 12 Wochen geschlachtet und die Schlachtkörperzusammensetzung ermittelt. Die Gefiederfarbe hatte einen signifikanten Einfluss auf das Gewicht von Schlachtkörper, Kopf, Ständer, Muskelmagen, Flügel, Schenkel und Innereienfett (P < 0,05). In der Regel waren die gelb und schwarz gefiederten Gänse

5 Saatci et al.: Effects on geese carcass 65 Table 3. Effects of fattening periods, feather colour and sex on slaughter yield and yields of different carcass parts (%) Einfluss der Mastdauer, der Gefiederfarbe und des Geschlechts auf die Schlachtausbeute und die Anteile verschiedener Schlachtkörperteile Dressing percentage of hot carcass Dressing percentage of cold carcass Traits (%) Blood Head Foot Heart Liver Fattening periods * * * 10 Weeks 67.19± ± ± ± ± ± ± Weeks 67.70± ± ± ± ± ± ±0.06 Colour * Black 66.74± ± ± ±0.06 ab 3.29± ± ±0.08 White 68.11± ± ± ±0.06 b 3.15± ± ±0.09 Piebald 67.81± ± ± ±0.06 a 3.30± ± ±0.09 Yellow 67.11± ± ± ±0.06 a 3.41± ± ±0.09 Sex * - Male 67.15± ± ± ± ± ± ±0.06 Female 67.74± ± ± ± ± ± ±0.07 Traits (%) Gizzard Spleen Neck Wing Leg Chest Back Total internal fat Fattening periods - * * * * 10 Weeks 3.76± ± ± ± ± ± ± ± Weeks 3.74± ± ± ± ± ± ± ±0.26 Colour * Black 3.73± ± ± ± ± ± ± ±0.38 ab White 3.86± ± ± ± ± ± ± ±0.39 a Piebald 3.57± ± ± ± ± ± ± ±0.40 b Yellow 3.83± ± ± ± ± ± ± ±0.39 ab Sex - - * * Male 3.64± ± ± ± ± ± ± ±0.27 Female 3.86± ± ± ± ± ± ± ± = (P > 0.05), * = P < 0.05, (a, b) differences between the groups having different superscripts are significant (P<0.05).

6 66 Saatci et al.: Effects on geese carcass schwerer, während die Gänse der Rasse Piebald am leichtesten waren. Die relativen Gewichte von Leber und Muskelmagen waren bei den 10 Wochen alten Gänsen am höchsten, während die Anteile von Brust, Rücken und gesamtem Innereienfett bei den 12 Wochen alten Gänsen am höchsten waren. Türkische Landgänse zeigten keine vorteilhaften Veränderungen am Schlachtkörper bei einer Verlängerung der Mastdauer auf 12 Wochen. Nur der Anteil des Brustfleischs hat noch etwas zugenommen. Es kann daher empfohlen werden, Türkische Landgänse bei Intensivhaltung mit 10 Wochen zu schlachten oder zur Senkung der Mastkosten in der 9. und 10. Mastwoche eine Weidemast zu betreiben. Stichworte Türkische Landgänse, Mastdauer, Geschlecht, Gefiederfarbe, Schlachtkörperzusammensetzung References ARSLAN, C., 2005: Effects of feeding by diets supplemented with grass meal and sugar beet pulp meal on growth, slaughter performance and some blood parameters in geese. Revue Med. Vet. 156, BUTLER, G., L.M. POSTE, A.A. GRUNDER, N.A. CAVE, B. PAWLUC- ZUK, 1991: Influence of breed, finisher diet, sex and age at slaughter on cooking and sensory properties of broiler geese. Arch. für Geflügelk. 55, CAVE, N.A., A.A. GRUNDER, G. BUTLER, A. FORTIN, B. PAWLUC- ZUK, 1994: Influence of age, sex and pre-slaughter holding conditions on live weight and carcass traits of broiler geese. Arch. für Geflügelk. 58, ÇELEBı, Ş., 1999: Erzurum da yetiştirilen yerli kazların bazı önemli kesim ve karkas özellikleri üzerine bir araştırma. Ulusal Hayvancılık 99 Kongresi, İzmir. 1999; FORTIN, A., A.A. GRUNDER, J.R., CHAMBERS, R.M.G. HAMILTON, 1983: Live and carcass characteristics of four strains of male and female geese slaughtered at 173, 180 and 194 days of age. Poultry Sci. 62, GRUNDER, A.A., N.A. CAVE, B. PAWLUCZUK, G. BUTLER, L.M. POSTE, 1991: Influence of breed, finisher diet, age and sex on liveweight and carcass traits of broiler geese. Arch. für Geflügelk. 55, HROUZ, L., 1988: Growth and development of Bohemian geese (Anser anser). British Poultry Sci. 29, ISGUZAR, E., A. TESTIK, 1999: An investigation on local genotypes of waterfowl in Isparta province of Turkey, 12 th European Symposium on Waterfowl, Adana, Turkey, JONES, R., 1984: A standard method for the dissection of poultry for carcass analyses. The west of Scotland Agriculture College, Auchincruive Ayr Technical note. No: 222. KIRCHGEßNER, K., D. JAMROZ, K. EDER, E. PAKULSKA, 1997: Carcass quality and fatty acid composition in growing geese fed various rations. Arch. für Geflügelk. 61, NRC, 1994: Nutrient requirements of poultry, 9 th revised edition, Natioanal Academy Press, Washington, DC, USA. PUCHAJDA, H., J. WEIS, 1988: Evaluation of finishing performance of different breeds and types of young geese. Acta Zootechnica Uni. Agr. Nitra 44, SAATCI, M., T. KIRMIZIBAYRAK, A.R. AKSOY, M. TıLKı, 2005: Egg weight, shape index, hatching weight with interrelationship among these traits in different feather coloured Turkish native geese. Turk. J. Vet. Anim. Sci. 29, TıLKı, M., Ş. İNAL, 2004: Türkiye de yetiştirilen degişik orijinli kazların verim özellikleri. III. Kesim ve karkas özellikleri. Turk. J. Vet. Anim. Sci. 28, TıLKı, M., M. SAATCI, T. KIRMIZIBAYRAK, A.R. AKSOY, 2005: Effect of age on growth and carcass composition of native Turkish geese. Arch. für Geflügelk. 69, Correspondence: Mehmet Akif Ersoy University, Veterinary Medicine Faculty, Department of Animal Science, 15100, Burdur, Turkey; m_saatci@hotmail.com