Use of watermelon waste minimally processed in the feeding of tilapia

The study proposed to assess ways for inclusion of watermelon waste in feed for tilapia. Thus, three tests were conducted: 1st – measuring the chemical composition of experimental feeds; 2nd – evaluating the digestibility of feed for fish and 3rd – determining the level of inclusion of waste in feed for tilapia. The following treatments were analyzed: T1 – reference diet; T2 – kiln-dry waste and introduced in 30% in the bran feed; T3 – kiln-dry waste and introduced in 30% in the pellet diet; T4 – sun-dried waste and introduced in 30% in the bran feed; T5 – sun-dried waste and introduced in 30% in the pellet feed. The variables analyzed were: chemical composition, coefficient of digestibility, metabolic energy, weight gain, feed intake and feed conversion. The T4 and T5 treatments showed no significant difference, with higher metabolic energy and digestibility coefficient, and are therefore chosen to perform the performance test. It was observed that the weight gain decreased quadratically (p<0.01) while increasing the level of inclusion of the waste in the diet. The feed intake and feed conversion were affected by the physical form of diet.