BIOREPRODUKSI DAN HUBUNGAN PANJANG-BOBOT TERHADAP FEKUNDITAS PADA IKAN LALAWAK (Barbonymus balleroides)
Authors: Kusmini Irin Iriana , Putri Fera Permata , Prakoso Vitas Atmadi 
Published: February 2019

Eksploitasi ikan lalawak (Barbonymus balleroides) yang berlebihan dari alam mengakibatkan langkanya jenis ikan ini di beberapa perairan aslinya. Sebelum ikan ini diperkenalkan sebagai komoditas budidaya, masih diperlukan lebih banyak lagi informasi mengenai aspek bioreproduksi ikan lalawak yang telah dipelihara pada lingkungan budidaya. Tujuan dari kegiatan ini adalah untuk mengevaluasi produktivitas ikan lalawak yang dipelihara pada lingkungan budidaya melalui pengamatan bioreproduksi dan hubungan panjang-bobot terhadap fekunditas. Sampel induk ikan lalawak betina yang diambil sebanyak 15 ekor, kemudian dipilih lima ekor induk betina yang telah matang gonad dengan ciri-ciri seluruh badannya terasa kasar apabila diraba, perut membesar ke arah posterior dan terasa lunak, genital mengembang, serta berwarna kemerahan. Data yang dikoleksi berupa panjang total, bobot badan, bobot gonad, fekunditas, diameter telur, dan indeks kematangan gonadnya. Hasil penelitian menunjukkan bahwa kisaran fekunditas ikan lalawak adalah 1.920-2.236 butir/g bobot gonad, dan 83-352 butir/g bobot badan induk dengan rata-rata diameter telur 0,87-1,10 mm. IKG berkisar 3,73%-18,36% dari kisaran bobot induk 85,32-264,8 g. Hubungan antara bobot badan dengan bobot gonad ikan lalawak digambarkan dengan persamaan linear y= 5,829ln (x) + 0,691 (r= 0,874); sedangkan hubungan panjang badan terhadap bobot gonad digambarkan dengan persamaan y= 28,52ln (x) - 38,10 (r= 0,7487). Pada ikan lalawak, hubungan bobot badan dengan fekunditas lebih erat dibandingkan dengan hubungan panjang badan terhadap fekunditas. Hasil pengamatan juga menyimpulkan bahwa ikan lalawak tergolong ikan yang memijah secara parsial.Over-exploitation of lalawak (Barbonymus balleroides) from its natural habitat had significant negative impacts on its availability. Before it is introduced as aquaculture commodity, more information about its reproductive biology in aquaculture environment needs to be well observed. The aim of this study was to determine the productivity of lalawak reared in aquaculture environment through observation of bioreproductionand relationship between fecundity and body length-weight of lalawak. Samplewas randomly taken from fifteen individuals female. From those samples, gonads were taken from five mature females for reproduction observation, by which the mature females were selected following specific criteria such as : their body feels rough if touched;enlarged abdomen posteriorly and felt soft; fluffy and reddish genital. Data collection consisted of measurement of the total length, body weight, gonad weight, fecundity, egg diameter and gonadosomatic index (GSI). The results revealed that the fecundity of lalawak ranged from 1,920 to 2,236 eggs/gof gonad weight and 83 to 352 eggs/g of body weight with average diameters of eggs ranged from 0.869 to 1.10 mm. GSI values ranged from 3.73 to 18.36% of 85.32 to 264.8g of body weight. The relationship between body weight and gonad weight of lalawak was described by the linear equation of y= 5,829ln (x) + 0.691 (r= 0.874), while the body length relationship to the gonad weight was described by the equation of y= 28,52ln (x) - 38.10 (r= 0.7487). Fecundity relationship with body weight of lalawak was closer than the length. The observations also concluded that lalawak is classified as partial spawning.