Effects of various dietary carbohydrate sources on the growth performance and body composition of the dog conch, Laevistrombus canarium

This study investigates the effects of dietary supplementation with various carbohydrate sources on the growth and dietary nutrient utilization ef fi ciency of a 0.72-g dog conch, Laevistrombus canarium . Five treatment diets had supplementation with alpha-starch (Sta), dextrin (Dex), pullulan gum (Pg), xanthan gum (Xg), and carboxymethyl cellulose (CMC). At the end of the feeding trial, the best growth performance (weight gain, 442.23%) and diet ef fi ciency (protein ef fi ciency ratio, 1.25, and feed conversion ratio [FCR], 2.04) were exhibited by the dog conch fed the Sta diet, whereas the lowest growth performance was observed in the dog conch fed the Xg and CMC diets. Dog conch fed the Sta (2.04) diet had a lower FCR than dog conch fed the other experimental diets (3.92 e 5.46). Apparent dietary digestibility (ADD) was signi fi cantly higher in dog conch fed the Sta diet than in the dog conch that were fed the other experimental diets. The ADD of protein was signi fi cantly lower in the dog conch fed the CMC diet than in those fed the other dietary treatments. The lowest ADD for energy was observed in the dog conch fed the CMC diet, followed by the Xg diet and Pg diet. Moisture, crude protein, and muscle crude lipid were affected by the carbohydrate source. An increase in carbohydrate complexity in the diet led to an enhancement of crude protein content and muscle crude lipid content. Compared with the other diets, the Sta diet yielded a signi fi cantly greater improvement in all shell parameters. These fi ndings indicate that dog conch fed a Sta diet demonstrate the best growth parameters, feed ef fi ciency, and ADD; therefore, diets supplemented with Sta are suitable for improving dog conch growth.