Latin american journal of aquatic research vol. 52 num. 1 lang. en
- Channel catfish, a species with potential deposition of human-beneficial fatty acidsel mayo 18, 2024 a las 8:14 pm
ABSTRACT Fatty acids from fish are of great interest for human consumption, and the channel catfish (Ictalurus punctatus) is one of the most important aquaculture species in Mexico and perhaps in other countries with similar resource endowments. Channel catfish occupy a trophic level that theoretically and potentially allows the retention and de novo biosynthesis of long-chain fatty acids (FAs), essential for human nutrition and health. Here, we present an overview of the main features of FAs, their reported average levels and extreme values in channel catfish assessments, and their correlations. The importance of FAs for human consumption and some implications for future research are discussed.
- Physiological role of genes involved in taurine biosynthesis in fishes and in silico approach to determine transcription factors in their promoters’ zoneel mayo 18, 2024 a las 8:14 pm
ABSTRACT Taurine, an amino sulfonic acid that is sometimes referred to as an amino acid, is endogenously synthesized by the action of the key genes/enzymes: cysteine dioxygenase (cdo), cysteine sulfonate decarboxylase (csad), glutamate decarboxylase (gad), and 2-amino ethanethiol dioxygenase (ado). The taurine transporter (taut) also distributes this taurine formation across the plasma. These genes have been identified as important in different physiological processes such as reproduction, digestion, olfactory, visual, circulatory, and muscular systems. Thus, a literature review of these genes in fish has been described in the present work. Moreover, there is null information regarding the study of regulatory elements such as transcription factors (TFs) in taurine biosynthesis and transportation genes of fishes. In this interest and taking advantage of the availability of different sequence databases, bioinformatics can be applied as a first approach for an in silico identification of the putative TFs and transcription factor binding sites (TFBS) that might play an important role in regulating these genes. The results showed that some are commonly shared, whereas TFs and TFBs vary among fish species. Hence, binding sites for homeobox protein BarH-like 1 (BARX1), brain-specific homeobox protein homolog (BSX), helicase-like transcription factor (HLTF), homeobox protein Hox-A7 (HOXA7), homeobox protein Hox-B3 (HOXB3), homeobox protein Hox-B6 (HOXB6), homeobox protein Meis1 (MEIS1), homeobox protein Meis3 (MEIS3), nuclear factor of activated T cells 1 (NFATC1), and homeobox protein Nkx-6.2 (NKX6-2) were commonly found in the promoter regions of genes involved in taurine transportation and biosynthesis. Additionally, our results suggested that the frequency of HOXB3, a transcription factor involved in development, has repetitive TFBS sites in the promoter region of all species analyzed in the present study. Although bioinformatics gives us an approach to determine putative TFs and TFBS, further work is needed to verify how the found regulatory elements play a key role in taurine biosynthesis and transportation.
- Biochemical composition and condition of wild blackfin snook Centropomus medius through the reproductive cycleel mayo 18, 2024 a las 8:14 pm
ABSTRACT The blackfin snook, Centropomus medius, is a valuable fish in American and Mexican markets, mainly from catches. Nonetheless, information and studies about the biology of this species still need to be made available; thus, its aquaculture should be developed. This study aimed to describe the seasonal changes of proximate composition during a reproductive cycle of C. medius, analyzing differences between tissues and their changes related to the reproductive process. The snook specimens were collected in Magdalena Bay, Baja California Sur, Mexico, and measured every month from September 2001 to November 2002. Liver, gonads, muscle tissue, and intraperitoneal fat (IPF) were sampled and weighed. The gonadosomatic index (GSI), hepatosomatic index (HSI), IPF ratio, and condition factor index (K) were calculated. The biochemical composition was analyzed in the gonad, liver, and muscle. The reproductive period (RP) of wild C. medius in Baja California Sur, Mexico, was from June to December. The spawning period was recorded at summer temperature (25-30°C) and photoperiod (>13 h daylight) starting in September. High GSI values (gonad development), low HSI values (lipid reserve mobilization), low IPF, and low K ratio were related to elevated temperatures. Moreover, variations were observed in protein, total lipid, triglycerides, and glycogen content in muscle, liver, and gonad according to the reproductive phase. A positive correlation was demonstrated between protein contents in muscle, gonad, and K, with lower concentrations during RP, while liver protein composition showed an opposite pattern. Lipids were mainly present in the liver, and the concentration decreased during RP while muscle increased. The results obtained in this study show differences in the proximate analyses in the liver, muscle, and gonads throughout the year concerning different phases of the reproductive cycle, indicating a great dependence of this process on the mobilization of reserves during C. medius reproduction. Therefore, understanding the feeding requirements to pursue the management of this species in captivity for aquaculture development is greatly important.
- Evaluation of protein and lipid ingredients through in vitro digestibility for tropical gar (Atractosteus tropicus) juvenilesel mayo 18, 2024 a las 8:14 pm
ABSTRACT Tropical gar (Atractosteus tropicus) is an ecologically, culturally, economically, and scientifically important species. Therefore, it is essential to know the available resources to design feeds for the culture of this species. This study evaluated the in vitro digestibility of meals and oils commonly used in aquaculture, using crude extract of the stomach and intestines of A. tropicus juveniles. We used the pH stat titration system to determine the degree of hydrolysis (DH%), the concentration of amino acids released (mg g of meal−1), and the speed of hydrolysis (SH%) of various animal and vegetable ingredients. The relative digestibility of each protein ingredient was calculated using bovine hemoglobin for acid digestion and Hammersten bovine casein for the alkaline phase as reference ingredients (100% digestibility). For lipid ingredients, fish oil was used as a reference. The highest relative digestibility for protein ingredients was observed with fish, crustaceans, beef, poultry meat and offal, and beef blood meals. The best lipid SH was observed with soybean lecithin and cod liver, soybean, olive, maize, and canola oils. It is possible to use a wide variety of terrestrial animal proteins and vegetable oils for manufacturing a diet for A. tropicus rearing.
- Fish community, seasonal movement and habitat use in a subtropical coastal lagoonel mayo 18, 2024 a las 8:14 pm
ABSTRACT Coastal lagoons are environmentally and naturally dynamic areas crucial for fish reproduction and nursery. Thus, this research aims to evaluate the importance of the species performing their biological processes and development in this ecosystem. For this purpose, a subtropical coastal lagoon in the Gulf of California was taken as a case study, where four sampling seasonal campaigns were performed within the lagoon (internal zones) and the marine environment (external) nearby zones from 2016 to 2017. Diversity, evenness, and dominance indices were determined, and the number of individuals, size, length at first maturity, and reproductive period of each species were analyzed to obtain fish use of the lagoon. This coastal lagoon shows a high abundance of juvenile organisms in the cold season, whereas mature adults were mostly present during the warm season. Environmental variables influencing fish species development and distribution, such as sea surface temperature, salinity, and chlorophyll-a, were detected. To conclude, the subtropical coastal lagoon in the Gulf of California is an important nursery area where reproduction occurs mostly near adjacent areas.