Comparative skeletal ontogeny and allometric growth pattern in common and butterfly-tail goldfish, Carassius auratus

The early stage of development is a vital period in the life cycle of fish in terms of achieving a suitable efficiency for survival. Knowing about fish growth patterns, including morphological changes and normal skeletal development, can be useful for optimizing hatchery production and monitoring and managing fish populations. This study aimed to survey allometric growth patterns and skeletal trait changes of the most popular variety of Carassius auratus, butterfly tail goldfish compared with its common strain during development. For the morphological part, specimens were photographed from the lateral view with a digital camera, and seven morphometric traits were measured. The allometric growth patterns were calculated as a power function of total length, and the inflexion points of growth curves were extracted. To study skeletal structure, specimens were cleared and stained with alizarin red for bone and alcian blue for cartilage. The positive allometric growth of the head, along with the onset of formation of its skeletal structures at the first-day post hatch that was observed in two studied strains, indicate the importance of the sensory system, nutritional and respiratory organs, which has a great effect on increasing survival rate. The most significant difference between common and butterfly goldfish was the formation and development of caudal fin. The formation process of tail skeletal elements was begun earlier in butterfly goldfish, and the growth pattern of TaL was approximately twice as fast as the common strain.

کلیدواژه ها:

Ornamental fish ، Development ، Osteology ، Goldfish ، Carassius auratus