Aetiology of skeletal deformity in a Barbus grypus (Heckel, 1843) fish: clinical and radiological studies

Defining desired genetic gains for Pacific white shrimp (Litopenaeus vannamei) breeding objective using participatory approaches

The objective of this study was to define desired genetic gains from economically important traits of Pacific white shrimp (Litopenaeus vannamei) using participatory approaches. Two questionnaires were sent out to 100 Pacific white shrimp farmers in all five Iranian shrimp farming provinces. Questionnaire A (Q-A) includes management factors and farming environments. Moreover, in this questionnaire, farmers were asked to rank the fourth most important traits in shrimp among 10 economic traits in the list for genetic improvement. In questionnaire B (Q-B), priorities of the four traits with the highest value were obtained using pairwise comparison. The results showed that the four most important traits were white spot syndrome virus resistance (WSSV), growth rate before 4 months (GR), acute hepatopancreatic necrosis disease resistance (AHPND), and female total weight at ablation (FTW). Medians of the best individual preference values were WSSV (0.222), GR (0.173), AHPND (0.157), and FTW (0.053). Most disagreements were found between the social group preference values in the commercial products and water salinity categories. Desired genetic gains were 1.71%, 1.57%, 0.53% and 0.31% for GR, AHPND, WSSV and FTW, respectively. This study highlighted that despite environmental and management differences, participatory approaches can achieve desired genetic results for Pacific white shrimp breeding programme.

Skeletal deformities and meristic trait variations are common in the intertidal fish Bathygobius cocosensis (Perciformes-Gobiidae)

Extreme environmental conditions, such as temperature, can lead to meristic trait variation and skeletal deformities, which may have major impacts on individual fitness. As intertidal ecosystems experience rapid temperature and physicochemical fluctuations, intertidal fish living and reproducing in these environmental conditions may have phenotypes influenced by such variable environments. The impact of intertidal variability on fish development, however, has not been previously investigated. Skeletal deformities and meristic traits were assessed for Bathygobius cocosensis, a common intertidal fish living across the Indo-Pacific region, using a clearing and staining method on 72 individuals. Over 87% of individuals presented meristic variation and over 70% exhibited at least one type of skeletal deformity, mostly recorded in the caudal fin area. The unexpected prevalence of skeletal deformities among this intertidal fish population suggests that such deformities may be suitable markers to evaluate an individual's stress exposure during development and the subsequent fitness effects.