There are many benefits of promoting of native chickens for rural poultry development in Indonesia. They are commonly raised in many areas of Indonesia and play a major role in food production, providing the main source of dietary animal protein for many people. They are often called “non-breed chickens"— (“or (“buras") to differentiate them from modern commercialized chicken breeds. There are at least 34 kinds of native chickens in Indonesia. Some of the more common native chickens, namely Ayunai, Balenggek, Banten, Bangkok, Burgo, Bekisar, Cemani, Ciparage, Gaok, Kampung, Kasintu, Kedu, Pelung, Lamba, Maleo, Merawang, Nagrak, Nunukan, Nusa Penida, Olagan, Sedayu, Sentul, Sumatera, Tolaki, Tukung, Wareng, Sabu, and Semau. Some of them are used for non-food purposes. Indonesia with its population is over 258.71 million people in 2016 has an annual level of protein consumption from poultry meat of 12.97 kg/capita/year and poultry eggs exceeded 190 eggs/capita/year. They accounted for about 10% of Indonesia‘s total meat consumption compared to broiler (55%), beef (19%), pork (8%), goat (7%), and others (1%) with its per capita meat consumption from livestock is still lower compared to many countries. There are three types of husbandry systems are used to raise native chickens in Indonesia. First, the extensive traditional system, farmers usually reared them ranged between 2 to 20 birds. Second, the semi-intensive with the bird numbers typically range from the least ownership of 25 birds to hundreds. Finally, there is professionally managed intensive system. The number of chickens reared is varies from hundreds to thousands.

Lake Kelapa Gading is an artificial lake located in Asahan district of North Sumatra province. Thepurpose of this study was to determine: 1) description of conditions of temperature, dissolved oxygenand pH vertically in the water for 24 hours, 2) production and consumption of oxygen in the waters ofLake Kelapa Gading. The study was conducted in March-April 2016 with preliminary and mainresearch activities. There are three observation stations are stations 1 (near KJA), station 2 (the areanear the settlement) and station 3 (outlet). The measured temperature ranges from 30-35 ºC.dissolved oxygen highest in the surface waters of 5.12 mg / l during the afternoon and the lowestoccurred at a depth of compensation of 0.64 mg / l when the weather is rainy. The measured pHvalue ranging between 6-9. In general there is a decrease in temperature, dissolved oxygen, and pHwith increasing depth. The highest percent saturation of 71.30 % in the surface waters. Comparisonbetween photosynthesis to respiration indicates that there has been a deficit in respiration is greaterthan the value of photosynthesis. dissolved oxygen concentration has reached a deficit at a depth of36.5 cm to reach at night.  Keywords: dissolved oxygen, lake, pH, saturation, temperature.

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1. PendahuluanIkan lemeduk (Barbodes schwanenfeldii) merupakan ikan air tawar yang termasuk kedalam genus barbodes. Ikan lemeduk ini mempunyai sinonim nama seperti Barbonymorus schwanenfeldii, Barbus pentazone schwanenfeldii, Barbus schwanenfeldii, Puntius schwanenfeldii (Fishbase, 2014). Sedangkan untuk nama lokalnya sendiri ikan ini sering disebut ikan kapiek, lempam, lempem, lampam, tenadak dan tengadak.Ikan lemeduk mempunyai ciri-ciri seperti bentuk tubuh pipih melebar dengan badan berwarna perak dan kuning keemasan, sirip punggung berwarna merah dengan bercak hitam pada ujungnya, sirip dada, sirip perut dan sirip dubur berwarna merah, sirip ekor berwarna oranye atau merah dengan pinggiran garis hitam dan putih sepanjang cuping sirip ekor (Gambar 1). Garis rusuk dengan sisik garis rusuk 35-36, terdapat 13 sisik sebelum awal sirip punggun dan 8 sisik antara sirip punggung dan gurat sisi. Untuk distribusi penyebaran ikan lemeduk ini mulai dari Sumatera, Borneo, Malaya dan Indochina (Kottelat dan Whitten, 1993).Ikan lemeduk termasuk salah satu spesies ikan hasil utama dari Sungai Belumai dan dijadikan ikan konsumsi dengan harga yang relatif tinggi. Akibat dari harga ikan lemeduk yang tinggi membuat adanya kecenderungan aktivitas penangkapan ikan di sepanjang Sungai Belumai.Lambat laun kondisi ini akan membuat kemungkinan ikan akan mengalami penurunan populasi jika tidak segera dilakukan pengelolaan dan pengembangannya. Upaya optimalisasi penangkapan, pemanfaatan, serta pelestarian ikan lemeduk di Sungai belumai masih sangat minim karena masih kurangnya data dan informasi biologi perikanan suatu jenis ikan menyebabkan upaya pengelolaan ikan tersebut tidak optimal.Sebagai bentuk antisipasi maka penelitian mengenai pola pertumbuhan dari ikan ini sangat diperlukan. Karena pola Acta Aquatica Aquatic Sciences Journal AbstrakPenelitian ini dilakukan di Sungai Belumai Kabupaten Deli Serdang Provinsi Sumatera Utara pada Bulan Mei dan juni 2014 di empat lokasi yang berbeda dengan menggunakan metode sensus. Tujuan dari penelitian ini untuk mengetahui aspek pertumbuhan (sebaran frekuensi panjang, hubungan panjang bobot, faktor kondisi dan koefisien pertumbuhan). Jumlah ikan lemeduk yang tertangkap adalah 55 ekor. Hasil penelitian menggambarkan bahwa populasi ikan didominasi oleh sebaran ukuran kelas panjang 174-194 mm. Hasil hubungan panjang berat menunjukkan bahwa pola pertumbuhan ikan bersifat allometrik negatif (b=2,565) dimana pertambahan panjang lebih cepat dibandingkan pertambahan berat. Nilai faktor kondisi ikan lemeduk (Barbodes schwanenfeldii) berkisar 0,946-1,059. Kata kunci: Sungai Belumai; pertumbuhan; Barbodes schwanenfeldii AbstractThis research was done in Belumai River Deli Serdang District North Sumatera Province. This research was conducted in May until June 2014 in four different locations by using census method. The purpose of this research is to know the aspect of growt (length frequency distribution, length-weight relationship, condition factor and growth coefficient). The number of lemeduk fish whic...

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