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Fish welfare has become a significant concern during the last decade. The issue of slaughter is getting the interest of many consumer organizations and fish growers, and suppliers. We need to take careful consideration to food fish slaughtering, and not only for an ethical reason. Numerous quality traits are in place already at the end of fish life. Nonetheless, other traits can be developed while the post mortem muscles are turning into consumer produce. Therefore, it is necessary to investigate ways to avoid the suffering of the fish before their processing. To improve the efficiency of the immobilizing and stunning process of the fish at the entrance of the fish plant, we investigated the use of CO2 in combination with low temperature. When combining CO2 to 2°C water temperature, fish were stunned and permanently immobilized within 20 min or less, while their core temperature was 3°C. Our results suggest that combining low temperature and bubbling CO2 in the fish receiving tank of the processing plant might be more appropriate for animal welfare. Therefore, we suggest continuing our experiments in the fish processing plant.

We present field observation results from October 2019 to February 2021 in Israeli fish farms. Surprisingly, two metazoan parasites, the larvae of Contracaecum multipapillatum and unidentified metacercaria N1, which disappeared from Israeli fish farming 30 years ago, were commonly found in the current study. The reappearance of these two helminths is likely related to changes in the management policy related to new regulations regarding bird-of-prey species. It means that farmers could have prevented parasitic infections by keeping away piscivorous birds from their fish ponds and by treating these ponds with appropriate compounds against the affected invertebrates.

A newly isolated Pacific white shrimp (Litopenaeus vannamei) beta-actin promoter SbaP and its derivative compact construct SbaP (ENX) have recently been demonstrated to promote ectopic gene expression in vitro and in vivo. To further explore the potential transduction application, this newly isolated shrimp promoter SbaP was comparatively tested with cytomegalovirus (CMV), simian virus 40 (SV40), polyhedrin (Polh), and white spot syndrome virus immediate early gene 1 (WSSV ie1) four constitutive promoters and a beta-actin promoter (TbaP) from tilapia fish to characterize its promoting function in eight different cell lines. Luciferase quantitation assays revealed that SbaP can drive luciferase gene expression in all eight cell lines including sf21 (insect), PAC2 (zebrafish), EPC (carp), CHSE-214 (chinook salmon), GSTEF (green sea turtle), MS-1 (monk seal), 293T (human), and HeLa (human), but at different levels. Comparative analysis revealed that the promoting activity of SbaP was lower (

The clariid catfish, Clarias batrachus commonly known as Magur, has declined drastically from natural habitats in India during the last decade. This fish is highly preferred fish by Indian consumers and has high market demand. As a result traders often substitute C. batrachus with a morphologically similar but supposedly banned exotic catfish, C. gariepinus, in India. This study uses rigorous morphological comparisons confirmed by DNA barcode analysis to examine the level of substitution of C. batracus by C. gariepinus in India. Our results indicate that up to 99% (in many cases) of the market samples sold as Magur or C. batrachus were in fact C. gariepinus.

Snakes represent a taxonomically underdeveloped group of animals in India with a lack of experts and incomplete taxonomic descriptions being the main deterrents to advances in this area. Molecular taxonomic approaches using DNA barcoding could aid in snake identification as well as studies of biodiversity. Here a non-invasive sampling method using DNA barcoding is tested using skin exuviates. Taxonomically authenticated samples were collected and tested for validation and comparisons to unknown snake exuviate samples. This approach was also used to construct the first comprehensive study targeting the snake species from Maharashtra state in India. A total of 92 skin exuviate samples were collected and tested for this study. Of these, 81 samples were successfully DNA barcoded and compared with unknown samples for assignment of taxonomic identity. Good quality DNA was obtained irrespective of age and quality of the exuviate material, and all unknown samples were successfully identified. A total of 23 species of snakes were identified, six of which were in the list of Endangered species (Red Data Book). Intra- and inter-specific distance values were also calculated, and these were sufficient to allow discrimination among species and between species without ambiguity in most cases. Two samples were suspected to represent cryptic species based on deep K2P divergence values (>3%), and one sample could be identified to the genus level only. Eleven samples failed to amplify COI sequences, suggesting the need for alternative PCR primer pairs. This study clearly documents how snake skin exuviates can be used for DNA barcoding, estimates of diversity and population genetic structuring in a noninvasive manner.