Morphological Identification and Ecology of the Red Jungle Fowl in Thailand, Laos and Vietnam

Morphological Identification and Ecology of the Red Jungle Fowl in Thailand, Laos and Vietnam Takao NISHIDA, Worawut RERKAMNUAYCHOKE1, Dan Gia TUNG2, Sukkongseng SAIGNALEUS3, Shin OKAMOTO4, Yoshi KAWAMOTO5, Junpei KIMURA, Kotaro KAWABE6, Naoki TSUNEKAWA, Hideki OTAKA and Yoshihiro HAYASHI7 College of Bioresource Sciences, Nihon University, Fujisawa-shi 252-8510, Japan 1 Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand 2 Hanoi Zoological Garden, Hanoi, Vietnam Faculty of Agriculture and Forestry, National University 3 of Laos, Vientiane, Laos Faculty of Agriculture, Kagoshima University, Kagoshima-shi 890-0065, Japan 4 Primate Research Institute, Kyoto University, Inuyama-shi 484-8506, Japan 5 6 Gene Research Institute, Kagoshima University, Kagoshima-shi 890-0065, Japan Graduate School of Agriculture and Life Sciences, The University of Tokyo, 7 Bunkyo-ku, Tokyo 113-8657, Japan (Received May 26, 2000; Accepted June 20, 2000) Abstract The morphological identification and ecological studies on the 3 subspecies of red jungle fowls were carried out in Thailand, Laos and Vietnam from 1994 to 1998. A total of 59 red jungle fowls and 47 hybrids with native chicken were collected and applied to the detailed morphological examination. For the ecological investigation, the hearing survey was performed at 55 localities. Fifty nine red jungle fowls were identified to 3 subspecies groups, Gallus gallus gallus with white earlobes, and G. g. spadiceus and G. g. jabouillei with red earlobes. The earlobe color was used as the most important index for the subspecies identification. Collecting places of individuals were also used as an effective index from the result of zoogeographical survey. There is an extensive zone of intergradation among the habitats of these 3 subspecies. The G. g. gallus inhabiting the continental Thailand, Cambodia, Laos and Vietnam expresses pure white earlobes covered completely with white patch, and the G. g. gallus inhabiting deep south Thailand expresses incomplete white earlobes. Therefore, the names of G. g. gallus type C (Continental) and G. g. gallus type I (insular) are reasonable to these zoogeographically differentiated two groups of G. g. gallus. Animal Science Journal 71 (5): 470-480, 2000 Key words: Jungle fowl, Subspecies identification, Ecology, Southeast Asia In the comprehensive monograph on the pheasants in the world, Delacour4) has described that all domestic breeds of poultry are descended from the red jungle fowl (Gallus gallus) and that the other 3 species played no part in their origin. The species Gallus gallus has geographically differentiated into 5 subspecies; G. g. gallus Linnaeus (Cochin-Chinese red jungle fowl), G. g. spadiceus (Burmese bird), G. g. jabouillei Delacour and Kinnear (Tonkinese bird), G. g. murghi Robinson and Kloss (Indian bird), and G. g. bankiva Temminck (Javanese bird). Since 1971, a Japanese research group has been doing research activities in Southeast Asia with interest in the evolution and domestication of jungle fowls. During these Corresponding: Takao NISHIDA, c/o Worawut RERKAMNUAYCHOKE (fax: 66(0)2-5611591, e-mail: fvetwwr @ku.ac.th) Anim. Sci. J. 71 (5): 470-480, 2000 470

Jungle Fowl in Southeast Asia investigations, we had collected many specimens of jungle fowls and their hybrids with native chickens for studies of their morphological and genetical relationships, as well as ecological data on the jungle fowls in Southeast Asian countries. Nishida et al.17) made a map of distribution of 5 subspecies of red jungle fowl and 3 other species of jungle fowl based on the results of their field investigations and on other publications. On the habitats of these 5 subspecies, the relation among 3 subspecies of G. g. gallus, G. g. spadiceus and G. g. jabouillei in Vietnam and Laos still remains obscure at the present time. The aim of this study is to confirm the morphological characteristics and the distribution of these 3 subspecies of red jungle fowls in continental Southeast Asia, and to clarify their ecological characteristics on the basis of the results in recent investigations of Thai, Lao and Vietnamese red jungle fowls performed from 1994 to 1998. Materials and Methods Animals Fifty-nine red jungle fowls and 47 hybrids with domestic fowl were used in this study. Of these birds, 9 jungle fowls consisting of 8 males and 1 female, and 30 hybrids consisting of 17 males and 13 females are stuffed specimens which were collected in Thailand from 1971 to 1972 for detailed morphological examinations. The number and the sex composition of the other live birds are as follows: 3 male and 3 female Thai jungle fowls, 10 male and 7 female Thai hybrids, 12 male and 2 female Lao jungle fowls, and 16 male and 14 female Vietnamese jungle fowls. Morphological identification of red jungle fowl In the former paper on the Southeast Asian jungle fowl in 198015), the following 6 indices were decided to select the red jungle fowl expressing typical characteristics on integument and its derivatives from the hybrids with native chicken. a) Skin: The skin of jungle fowl is so thin that the muscle underneath is visible, and it represents a semitransparent pink color. The skin of hybrids looses all its transparency and is tinged with yellow color varying with the thickness. b) Comb: The comb of the jungle fowl is small and thin, while its size and thickness are clearly increased by hybridization. c) Footscale and spur: The surface structure of the foot scale of jungle fowl is smooth. The spur and the digital claw of jungle fowl are slender and sharp, but they loose the sharpness in hybridization, becoming thick and dull. d) Plumage: The plumage of male jungle fowl shows a typical wild pattern expressed by black breast feathers and upper major and median secondary coverts, and by the reddish-brown anterior edge of the primary flights and the anterior vane of the secondary flights. The female jungle fowl expresses finely pencilled black markings and dark shaft color in the black feather and the wing covert, and its breast feather also expresses a typical salmon color. Some of these wild patterns are lost in hybrid individuals. e) Earlobe color: The earlobes of G. g. gallus collected in the area from southeast Thailand to south Vietnam are white, but those of the same subspecies in extreme south Thailand and West Malaysia are incomplete white or whitish red. Those of G. g. spadiceus and G. g. jabouillei are red. f) Body measurements: Measurements of the length of long bone and wing, the body weight, and the comb size and thickness are fully available as good criteria to select pure jungle fowls from hybrids, because all these measurements for hybrids result in figures intermediate between jungle fowl and domestic fowl. After taking the body measurements of each bird, the expression of characteristics on integument and its derivatives was checked in detail and was recorded using the indices above. Ecological study The hearing survey was made for the ecology of jungle fowls at 28 localities in Thailand, 25 localities in Laos and 6 localities in Vietnam from 1996 to 1998 (Fig. 1). The hearing way and items are shown in Tables 1 and 2. Morphological examination of gonadal activity To confirm the gonadal activity, 2 male and 1 female jungle fowls were examined under anesthesis with nembutal sodium solution. After the macroscopical observation and the measurement of the Anim. Sci. J. 71 (5): 470-480, 2000 471

NISHIDA, RERKAMNUAYCHOKE, TUNG, SAIGNALEUS, OKAMOTO, KAWAMOTO, KIMURA, KAWAEE, TSUNEKAWA, OTAKA and HAYASHI longest length of gonad, the gonads were fixed in Bouin's fluid and 10% formalin phosphate buffered hematoxylin and eosin to be observed by light microscopy. Results and Discussion Identification of red jungle fowl During the field investigation in Thailand, Laos and Vietnam, there were some chances to observe a jungle cock in a farmyard chicken population and his mating behavior with domestic hens. Therefore, a jungle fowl expressing its typical external genetic characters must be distinguished from its hybrids with native chicken for identification of subspecies. Delacour4) indicated a key to red jungle fowl (male) as follows: * Numbers 2, 3 and 4 indicate jabouillei, murghi and gallus, respectively. According to Robinson and Kloss19) and Kinnear10), no constant differences could find in the color of plumage or the shape of neck hackles of red jungle fowl samples collected in India and north Vietnam. Using a total of 59 jungle fowls consisting of 3 subspecies, G. g. spadiceus, G. g. gallus and G. g. jabouillei, and 45 hybrids, the authors definitely compared the morphological features of these jungle fowls and hybrids. No differences were observed in the feather color among the 3 subspecies through the Anim. Sci. J. 71 (5): 470-480, 2000 472 eclipse after breeding season7) and the other seasonal changes. Therefore, the earlobe color and the habitat of jungle fowls have been used as the key points for the identification of these subspecies. Concerning morphological differences of common integument and its derivatives except the feather color and pattern, a body conformation estimated by the somatometry must be one of the most important key points. The body conformation of red jungle fowls will be discussed in the following paper based on the result of somatometrical studies using enough numbers of birds. In this study, the morphological estimation is limited to the common integument and its derivatives for the identification of red jungle fowl subspecies. On the subspecies of red jungle fowl, the result of our first field investigation in Thailand (1972) coincided with Lekagul's description in his famous book of Thai birds11); gallus with white patch on earlobes occuring in the eastern plateau and southeastern provinces, and spadiceus lacking the white patch on earlobes found in the northern, western and southern provinces. According to the results of the studies on 3 subspecies of red jungle fowl in Thailand, Laos and Vietnam from 1994 to 1998, the G. g. gallus extends his habitat to southern Vietnam via Laos and Cambodia (Fig. 1). The whole surface of earlobes of subspecies, G. g. gallus, inhabiting north- and southeastern Thailand and south Indo-Chinese Peninsula, is covered with white patch which often extends to surrounding face. On the other hand, we had found that the jungle fowl inhabiting the southern provinces in peninsular Thailand showed earlobes varying from red to whitish-pink in the first investigation on Thai red jungle fowl in 1971. The investigation on jungle fowls extended into Malaysia in 1974 and confirmed the presence of red jungle fowl expressing the same earlobe color as that of the southern Thai birds varying from whitish-pink to grayish-white. The Philippine red jungle fowls, of which 9 birds were collected from Luzon, Mindro, Negros and Palawan in the first (1971) and second (1975) field investigations in the Philippines were also identified with G. g. gallus Linn. on the basis of their various white earlobes. According to the description of red jungle fowl in Malaysia

Fig. 1. Map of Thailand, Laos and Vietnam, showing the locations of ecological survey of jungle fowl. Numbers in the figure refer to the community numbers in Tables 1 and 2. Localities inhabited by the G. g. spadiceus and the G. g. jabouillei are shown with each locality number in a black circlet, and those inhabited by the G. g. gallus are shown with the locality number in a white circlet. (Madoc13) and Wells21) and in the Philippines (Gilliard6), and Rand and Rabor18)), these birds in both countries belong to the subspecies of G. g. gallus. The red jungle fowl having various earlobes covered incompletely with white patch was also confirmed in Sumatra, Lombok and Slawesi during the field investigations in Indonesia from 1977 to 1987. However, a question still remains in identification of jungle fowls having a various whitish earlobes, because the earlobe color may be affected not only by the action of a single Anim. Sci. J. 71 (5): 470-480, 2000 473

NISHIDA, RERKAMNUAYCHOKE, TUNG, SAIGNALEUS, OKAMOTO, KAWAMOTO, KIMURA, KAWABE, TSUNEKAWA, OTAKA and HAYASHI gene but also by complicated factors such as disappearance of sinusoidal capillaries in the superficial layer of dermis, thickening of the dermal dense connective tissue layer and deposition of purines in the subepidermal layer12). On the earlobe color, white earlobes are found in a few breeds of chickens, but red earlobes are found in many breeds of chickens. The differences among individuals were great in the histological characteristics of white earlobes12). According to many other authors, the nomenclature of subspecies G. g. gallus has been adopted for the red jungle fowl with white earlobes varying from whitish pink to pure white; these birds inhabit the southeast Thai, Malay Peninsula, Sumatra, Slawesi and Philippine Islands. We presume that there is a geographical differentiation in the large population of G. g. gallus subspecies occuring in the wide area from Continental Southeast Asia to Insular Southeast Asia; the G. g. gallus differentiates into two groups, Continental gallus, G. g. gallus type C, and Insular and Peninsular gallus, G. g. gallus type I as shown in Fig. 1. Distribution of jungle fowl The hearing surveys had been carried out in 59 localities including 3 localities where jungle fowls were captured as shown in Fig. 1. The result of the surveys and the locality names are shown in Tables 1 and 2. Localities inhabited by red jungle fowl subspecies with the red earlobes, G. g. spadiceus and G. g. jabouillei, are shown with each locality number in a black circlet, and those inhabited by the subspecies with the white earlobes, both types of G. g. gallus, are shown with the locality number in a white circlet in Fig. 1. Concerning the distribution of jungle fowls, Nishida15) made a new map based on Hutt's map inserted in Genetics of the Fowl8) and on other publications in ornithology. Unfortunately, the comprehensive work on the exact distribution of jungle fowls has never been reported since Beebe's monograph world pheasants was published in 19312). Since 1971, a Japanese research group on native farm animals in Asia has been carrying out research activities in Southeast Asia. Through these field investigations we have collected many specimens of jungle fowls and their hybrids with the native chicken of as well as ecological data on the jungle fowls found in the Philippines, Thailand, Malaysia, Indonesia and Bangladesh. Our views on the exact distribution, the identification of subspecies and the ecology of jungle fowls are described on the basis of the findings obtained from their morphological and genetical studies and ecological data. Thailand is zoogeographically divided into 6 regions, northern, central, western, southern, southeastern and northeastern parts. It has been known that the G. g. gallus with white earlobes distributes in the north- and the south-eastern parts, and the G. g. spadiceus with red earlobes inhabits the other 3 parts except the central plain10). In order to confirm the distribution of these two subspecies, we collected the exact information about the distribution and ecology of jungle fowls at more than forty places dispersed through the whole 6 regions in Thailand in 1971 and 1972. The results of these investigations coincide with Lekagul's description11), except that the red jungle fowl inhabiting the southern provinces in Peninsular Thailand shows the earlobe color varying from pure red to variable white. The findings in Thailand, Laos and Vietnam show that the habitats of G. g. spadiceus and G. g. gallus in Thailand are divided by Phang Hoei range. The borderline extends north from Chonburi along the range to the Mekong, and then it turns to the eastern side along the line connecting Vientiane (Laos), Ky Son and Ha Tinh (Vietnam). The coast from Ha Tinh to Haiphong is the eastern end of habitat of G. g. spadiceus, because the southern extension of G. g. jabouillei's habitat seems to be inhibited by a natural barrier of the Hong River 20) and by the Hong delta which is one of the largest population areas in the Northern Vietnam. Furthermore, there is a fact that Hanoi Zoo caught a G. g. spadiceus in Nghe An province in 1998 (see locality number Fig. 1). 58 in Table 2 and The border between the habitats of G. g. spadiceus and Malaysian G. g. gallus (type I) seems to be present in the extreme southern Thailand, but it is still obscure, because the earlobe color has never been recorded in Yala and Narathiwat provinces21). The northern border of habitats of 2 subspecies, G. g. Anim. Sci. J. 71 (5): 470-480, 2000 474

Jungle Fowl in Southeast Asia Table 1. Results of Morphological and Ecological Survey on Jungle Fowl in Thailand Anim. Sci. J. 71 (5): 470-480, 2000 475

NISHIDA, RERKAMNUAYCHOKE, TUNG, SAIGNALEUS, OKAMOTO, KAWAMOTO, KIMURA, KAWABE, TSUNEKAWA, OTAKA and HAYASHI Table 2. Results of Morphological and Ecological Survey on Jungle Fowl in Laos and Vietnam 2) National P ark; 3) Province; 4) Northan limit of G. g. g. habitat, cited from Vo Qui, Birds of Vietnam, 1975; Anim. Sci. J. 71 (5): 470-480, 2000 476

spadiceus and G. g. jabouillei, is on the line connecting the base of Leizou peninsula, Nanning, Kunming and Xiaguan (China)3). A borderline between the habi- Jungle Fowl in Southeast Asia tude along the Hong to Haiphong (Vietnam). It seems to be difficult to confirm an exact distribution boundary of these 3 subspecies, because there is no doubt an extensive zone of intergradation between them as Delacour4) described in his monograph. There are wide intergradation zones between the habitats of 3 subspecies as shown in Fig. 1. The first intergradation zone between habitats of G. g. spadiceus and G. g. jabouillei is in the southern China, the second zone between habitats of G. g. spadiceus and G. g. gallus (type C) extends from Thailand to Vietnam via Laos, and the third one between habitats of G. g. spadiceus and G. g. gallus (type I) is in Thai- Malay peninsula. Ecology of the red jungle fowl Hearing surveys on the ecology and the interrelationship between the red jungle fowl and the native chicken had been performed at 28 localities in Thailand, 25 localities in Laos and 6 localities in Vietnam from 1994 to 1998. These results are summarized in Tables 1 and 2. Breeding season Habitats of jungle fowls in extreme northern Thailand and northern Laos and Vietnam, and the extreme southern China are included in the warm temperate climate area with rainfall at least ten times in the driest winter month as much as in the wettest summer month. Those in the most part of Thailand, and southern Laos and Vietnam are included in the tropical climate area with at least one month of dry season receiving rainfall of less than 24 inches. This establishment of 2 regions for habitats is coincident with Koppen's classification of climatic region in Southeast Asia5). A peak of breeding season of jungle fowl inhabiting the former (northern) area is limited in the late dry season (April or May), while the peak of that in the later (southern) area extends to the early dry season (December or January). Two male and one female adult birds were examined to confirm the gonadal activity at Saravan in southern Laos on January 23, 1998. Though the Anim. Sci. J. 71 (5): 470-480, 2000 477 testis length was about 10mm, all kinds of spermatogenic cells from spermatogonium to mature spermatozoon were recognized in the seminiferous tubules by the histological examination. There were no yellow follicles in the ovary of female adult bird. The results of the autopsy revealed that these 3 birds were in the breeding season but still not in an active breeding condition. The same inactive gonadal condition was confirmed in the field investigation on Nepalese red jungle fowl17). Three male and 2 female adult birds were also autopsied at Simiri in Tarai on December 10 and 11, 198915). All of their gonads were not in the active condition. Thai, Lao and Vietnamese red jungle fowls have a definite breeding season, but the beginning of the season varies with the differences in the local weather. A peak of the breeding season is in the period from December to April. In the breeding season, a female jungle fowl lays a clutch of 5 to 10 eggs in a nest. This clutch size is the same as the egg number counted by Beebe1) and Nishida15). The results given in Tables 1 and 2 indicate that a flock of Thai, Lao and Vietnamese red jungle fowl is composed of one to 5 males and 3 to 10 females, but in most cases only a single cock is observed. Thus, a flock probably consists of a male leader, 1 to 10 or more females and sometimes some of younger males as confirmed in the surveys on Indonesian15) and Nepalese jungle fowl17). Interrelationship between red jungle fowl and native chicken To clarify the interrelationship between the red jungle fowl and the native chicken, the hearing survey and the observation have been carried out in Thailand, the Philippines, Malaysia, Indonesia and Sri Lanka. The hearing survey on crossing between the red jungle fowl and the native chicken was performed at 21 localities in Thailand, 14 localities in Laos and 2 localities in Vietnam, and the hearing surveys on the catching way of the red jungle fowl was performed at 19 localities in Thailand, 19 localities in Laos and 2 localities in Vietnam (Tables 1 and 2). A clear interrelationship has been confirmed between the results of hearing surveys on crossing with native chickens and the catching way of jungle fowls as shown in Tables 1 and 2. There is a possibility of

NISHIDA, RERKAMNUAYCHOKE, TUNG, SAIGNALEUS, OKAMOTO, KAWAMOTO, KIMURA, KAWABE, TSUNEKAWA, OTAKA and HAYASHI Table 3. Results of Morphological and Ecological Survey on Jungle Fowl in South Thailand 1) National Park; 2) Wildlife Breeding Center; 3) Domestic fowl. mating between the red jungle fowl and the native chicken in the localities where native people have captured the jungle fowl by trapping, trapping with decoy and picking laid eggs from the nest. On the other hand, there is no possibility of crossing between them at the localities capturing the jungle fowl by shooting. The localities having the possibility of crossing between jungle fowls and native chickens distribute in the whole area of Thailand (Table 1), while the localities lacking the possibility of crossing between them are in Laos with the exception of three localities in the southern Laos (Table 2). In the Philippines, male jungle fowls have frequently been domesticated and used for a national pastime of cock fighting by the natives. The Philippine natives are very successful in catching the jungle cock alive by employing a live decoy picketed within a small corral snares14). The presence of the same trapping method was confirmed also in our investigation on Malayan jungle fowls in 1974. The domestication of jungle fowl is established in long and close interrelationship between the jungle fowl and the human being. First of all, the domestication of jungle fowl starts with a supply of the good feeding condition from the human to the jungle fowl. The shooting does not bring any harvest to the domestication of jungle fowl. Results of our ecological investigations in Thailand, Laos and Vietnam on the red jungle fowls may give an important suggestion to the domestication of jungle fowl in Southeast Asia. Appendix Supplementary field investigation on Thai red jungle fowl in 2000 To confirm the earlobe color of red jungle fowl inhabiting Narathiwat and Yala provinces in deep south Thailand, the field investigation has been carried out from January 30 to February 13 in 2000. During the investigation, the hearing survey and the detailed morphological examination on the external genetic characters of red jungle fowl have been done. According to results shown in Table 3 and Figure 2, we could identify morphologically the red jungle fowl inhabiting deep south Thailand to a subspecies of G. g. gallus type I (Insular) with various white earlobes. The body conformation of this type of G. g. gallus is not slender, and the tail feather is rather high and curves dorsally. Wells21) described geographical variation of red jungle fowl in Thai-Malay Peninsula as follows: "Subspecies spadiceus Bonnaterre 1792 (TL M alaka), of SW China and western SE Asia to N Sumatra (CLBS). The ear-wattle is non-contrasting red south to near the Thai/Malaysian border (but color unrecorded in Yala-Narathiwat); white in Malaysia". We also already confirmed various white earlobe color of Malayan red jungle fowl in our field investigation in 1974. In the distribution maps of jungle fowl shown by Delacour4) and Johnsgard9), Malay Peninsula and north Sumatra are included in the habitat of subspecies G. g. spadiceus. However, the non-contrasting red or Anim. Sci. J. 71 (5): 470-480, 2000 478

Jungle Fowl in Southeast Asia Fig. 2. Map showing locations of ecological survey of jungle fowl in the Thai-Malay Peninsula. Numbers in the figure refer to the community numbers in Tables 1 and 3. white earlobe color mentioned above by three authors4)9)21) are not included in the characteristics G. g. spadiceus. The results of our field investigation at 8 localities in deep south Thailand indicate that the habitat of G. g. spadiceus with red earlobes changes to that of G. g. gallus type I (Insular) with various white earlobes. The borderline between the habitats of both subspecies Acknowledgements The authors wish to heartily thank Dr. Thaveewat Tasanawat, Dean of Faculty of Veterinary Medicine, Kasetsert University (FVMKU), the members of Anim. Sci. J. 71 (5): 470-480, 2000 479 of FVMKU, the officers of National Park, Wildlife Reserve, Wildlife and Captive Breeding Stations, Department of Forestry Thailand, Dr. Verachai Virochasaengaroon, Chief of Pandang Besar Animal Quaratine Station, the members of Faculty of Agriculture and Forestry, National University of Laos, the officers of Provincial Agriculture and Forestry Depertment, Dr. Boumy Xaymountry, Chief of Epidemiology Section, Animal Health Division, Department of Livestock and Fisheries Laos, Mr. Le Sy Thuc, Director of Hanoi Zoological Garden (HZG) and Ms. Nguyen Cuc Phuong, Head of Breeding Center HZG, for their kind arrangements and coorperations in the investigations. This work is

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