In the present study, IL-1β cDNA was identified and analyzed from largemouth bass (Micropterus salmoides). Full length IL-1β mRNA was obtained using Rapid Amplification of cDNA Ends (RACE), which contains 78 bp 3′-UTR, a 455 bp 5′-UTR, and an open reading frame (ORF) of 702 bp coding for 233 amino acid residues. The molecular weight and theoretical isoelectric point of largemouth bass IL-1β protein was predicted to be 26.7 kDa and 6.08 respectively. A largemouth bass IL-1β phylogenetic analysis showed a close relation to the IL-1βs of striped trumpeter (Latris lineata), Chinese perch (Siniperca chuatsi), and Japanese sea bass (Lateolabrax japonicus). Peptidoglycan upregulated IL-1β in the spleen and head kidney, while lipopolysaccharide upregulated detectable levels of IL-1β in the spleen only. Largemouth bass, challenged with Nocardia seriolae (1.0 × 10⁶ cfu/mL), showed a significant increase in IL-1β at 3 and 5 days post infection (dpi) in the spleen, while in the head kidney significant expression was found at 2 and 3 dpi, peaking at 3 dpi. Furthermore, tumor necrosis factor α (TNF-α) showed significantly higher expression in the spleen at 3 and 5 dpi, and in the head kidney at 1 and 3 dpi, with expression decreasing at 5 dpi in both tissues.

Lymphocystic disease affects over 150 species of marine and freshwater fish worldwide. In this study, the lymphocystis pathogen was found in 2 (Amphiprion ocellaris and Amphiprion clarkii) of the 9 species of clownfish. Detection of lymphocystis disease virus (LCDV) was based on histopathological study, electron microscope observation of virus particles and gene sequence analysis from the MCP region. Infected A. ocellaris hosts showed sparse, multifocal, white, stiff, papilloma-like nodules on the body, skin, gills and fins; while, on A. clarkia, nodules were found on the operculum skin. Histopathologic study showed lymphocystic cells with an irregular nucleus, enlarged cytoplasm and intracytoplasmic inclusion bodies surrounded by the cell membrane. The viral particle presents virions 180–230 nm in diameter, hexagonal in shape with an inner dense nucleoid under transmission electron micrographs (TEM). From the ML polygenetic tree, the clownfish LCVD genotype was closely related to the LCDV strain from paradise fish, Macropodus opercularis (KJ408271) (pairwise distance: 92.5%) from China, then followed by the strain from Spain (GU320726 and GU320736) (pairwise distance: 90.8–90.5%), Korea (AB299163, AB212999, AB213004, and AB299164) (pairwise distance: 91.5–80.5%) and lastly Canada (GU939626) (pairwise distance: 83%). This is the first report of lymphocystis disease in A. clarkii in Taiwan.

As people’s focus broadens from animals on farms to zoos and aquaria, the field of welfare science and the public’s concern for animal welfare continue to grow. In captive animals, stress and its causes are topics of interest in welfare issues, and the identification of an objective method that can be used to assess animals’ stress as a physiological state is essential. Both behavioral and physiological parameters can be used as indicators in order to assess animal stress quantitatively. To validate this approach, acoustic activity and the sloughed scrape skin cortisol concentration were used to evaluate the animal welfare of captive beluga whales (Delphinapterus leucas). The acoustic activity (5 min at 10:00 am) of three captive D. leucas was routinely recorded by a transducer and analyzed using audio editing software. The calls were separated into three main categories: whistles, pulses, and combo calls. The sloughed scrape skin samples were collected non-invasively once a week from all three animals’ fluke and/or flipper. Cortisol was extracted using a modified skin steroid extraction technique, and detected via commercially available enzyme immunoassays. The results showed that the cortisol concentration increased by varying levels when the whales encountered the same event. In addition, the number and distribution of the calls changed along with the events. This indicated that the changes in the cortisol concentration and acoustic behavior may have reflected the fluctuations in the environment and body condition. Therefore, the scrape cortisol measurement and acoustic recordings could be used to monitor stress levels in captive beluga whales. We recommend that aquaria consider incorporating skin scrape cortisol and acoustic activity monitoring into their standards for animal welfare.