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Simple Summary: The presence of the Africanized bee on the American continent allowed hybridization processes, which led to a high genetic diversity. However, distinct morphotypes with unique characteristics emerge at different altitudinal levels across the continent. Ecuador possesses high biodiversity and offers ideal conditions for Africanized hybrid development. Nevertheless, it is crucial to identify the formation of morphotypes adapted to the area in order to propose conservation plans for these insects, since individuals with excellent behavior in both hygiene and defensiveness, desirable traits in Africanized bees, have been observed previously. Seventy-five samples were collected from 15 beehives in the central highlands of Ecuador (Tungurahua–Chimborazo) to assess Africanization in managed bee populations using wing geometric morphometric and mitochondrial DNA analyses. The results indicated that when grouping the apiaries based on altitudinal floors into 2600–2800, 2801–3000, and 3001–3274 m above sea level, differences (p < 0.001) were observed. The morphotypes were similar in the first two floors, but the third indicated that altitude plays a crucial role in the differentiation of populations. When comparing with the pure subspecies, we found differences (p < 0.001); the nearest Mahalanobis distance was for Apis mellifera scutellata (D2 = 3.51), with 95.8% Africanization via father in the area. The maternal origin of all patterns belonged to lineage A (A. m. scutellata), with seven haplotypes. The most frequent haplotypes were A26 and A1; however, the A1q haplotype was not detected at the national level or in nearby countries. The identified haplotypes do not coincide with A4, which is predominant in South Africa and Brazil. The results indicate a double origin due to their presence in North Africa and the Iberian Peninsula. The formation of specific morphological groups within ecoregions is suggested. [ABSTRACT FROM AUTHOR]

Penaeus spp. are the most cultivated type of shrimp because they have rapid growth and good adaptation to farming conditions. Due to diseases that result in high mortality and a decreased product quality, the cultivation of these shrimp globally, and in Cuba in particular, comes with the risk of significant financial losses. This study examined the effect of fructooligosaccharide (FOS, 1-kestose) on the growth and immune response of shrimp, as well as the multitude of Vibrio spp. and Pseudomonas spp. in Penaeus vannamei post-larvae under culture conditions. Fructooligosaccharide was applied in a completely randomized manner at a concentration of 0.4%, in both experimental groups with seventeen tanks each. In the results of this investigation, animals of greater weight (control 6.8 ± 0.2 mg; FOS 9.5 ± 0.3 mg; p < 0.001), length (control 1.1 ± 0.1 mm; FOS 1.3 ± 0.1 mm; p < 0.001), and survival (control 61.7% (95% CI of median 54.2–70.0); FOS 76.6% (95% CI of median 72.1–84.2); p < 0.001) were obtained when administered FOS relative to the control. An increase in the activity of proteases (p < 0.001), enzymes of the innate immune system such as phenoloxidase (p < 0.001), and lysozymes (p < 0.001) was observed, as well as an increase in the number of lectins (p < 0.001). Changes in the microbiota could be observed, with a reduction in Vibrio spp. and Pseudomonas spp. (control 2.4 × 103 ± 0.5 × 103; FOS 1.1 × 102 ± 0.3 × 102; p < 0.001). FOS improves the quality of the post-larvae of P. vannamei as reflected in the length, weight, and survival of the animals. Moreover, FOS stimulates the P. vannamei immune system through the enzymatic activities of phenoloxidase, lysozyme, and a number of lectins. The reduction in the population load of Vibrio spp. and Pseudomonas spp. might be a consequence of the improvement in the quality and immune system of P. vannamei. [ABSTRACT FROM AUTHOR]

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Abstract: Growth hormone (GH) release is a process that is well regulated by several factors, including GH secretagogues. GH can mediate the regulation of the fatty acid level and composition. The aim of this study was to determine the effect of a synthetic GH secretagogue peptide (A233) on the growth and fatty acid composition in tilapia (Oreochromis niloticus). To address this objective, we administrated a diet supplemented with A233 to juvenile tilapia for 60 days. The group fed with a diet supplemented with 600 μg of A233 per kg of feed increased in weight (4.81 ± 0.09 g) and specific growth rate (2.49 ± 0.03%/day) compared to the control diet group (3.63 ± 0.08 g, 2.07 ± 0.04%/day; respectively) (p < 0.001). In the muscle, the total lipids for the control diet group were higher than that in the group fed with 600 μg of A233 per kg feed; however, no differences were detected in the liver. In both tissues, the patterns of fatty acid composition and content were generally similar, with some exceptions. Tilapia fed with 600 μg of A233 per kg of feed showed, in liver and muscle, a significantly higher composition and content of n‐3 polyunsaturated fatty acids (such as 20:5n‐3, 22:5n‐3, 22:6n‐3) and n‐3/n‐6 PUFA than animals fed with the control diet. To our knowledge, this is the first report on the the effects of natural or synthetic GH secretagogues (GHS) on fatty acid composition, implying an increase in the nutritional quality of the tilapia. [ABSTRACT FROM AUTHOR]

This study examined the effects of Bacillus licheniformis strain CIGBC-232, isolated from the gut of shrimp Litopenaeus vannamei and having antagonistic activity against Vibrio harveyi, on the immunity and larval quality of L. vannamei at various ontogenetic stages, in two separate experiments: (1) PL2 to PL17 exposed to the strain CIGBC-232 under laboratory conditions (2) zoea I to PL8 exposed to the strain CIGBC-232 and EPICIN 3W probiotics under farming conditions. The first experiment showed that phenoloxidase, peroxidase and superoxide dismutase activities were improved in animals grown with CIGBC-232 compared to the untreated control. In tests, the resistance to osmotic stress was also enhanced. During the second experiment, animals treated with CIGBC-232 exhibited significant ( P < 0.05) increases in phenoloxidase activity (30-40% higher in zoea I- II, mysis II- III and PL 2-7) and in the respiratory burst (30% higher from PL 2 to 7) as compared to those animals that received EPICIN 3W. There was no significant difference in the lectins and agglutinins (except in PL1, 6 and 7), in peroxidase and superoxide dismutase activities, in the resistance to osmotic stress, nor in the survival rate among treatments. CIGBC-232 treatment was able to reduce, the level of presumptive Vibrio spp. with respect to EPICIN 3W treatment in the tank water as well as in animals. At the end of both experiments, the growth of shrimp, i.e. weight and length was increased by CIGBC-232 treatment. This study showed the probiotic effect of CIGBC-232, which appeared to have a better probiotic performance than EPICIN 3W treatment. [ABSTRACT FROM AUTHOR]

Acuabio 1 is a mixture of proteins and essential amino acids that exerts a stimulating effect in the development of aquatic organisms. It synchronizes and accelerates fish and shrimp larvae growth on early developmental stages, as well as increases the development and size of these animals. In this work, the stimulating effect of Acuabio 1 on the immune system of Litopennaeus vannamei shrimps was demonstrated by obtaining (5.4 x 106 hemocytes/mL) greater than the control group (4.3 x 106 hemocytes /mL). The hemolymph of treated animals showed higher lectin titers (16) than the control group (8). Animals treated with Acuabio 1 increased their phenoloxidase and peroxidase activities, indicating an enhanced oxidative defense. Furthermore, Acuabio 1 decreased the number of Vibrio spp. and Pseudomonas spp. colony forming units in the culture medium, suggesting a possible prebiotic function. All these properties make Acuabio 1 very attractive to improve the production, survival rate and quality of shrimp larvae. [ABSTRACT FROM AUTHOR]

Acuabio 1 is a mixture of proteins and essential amino acids that exerts a stimulating effect in the development on aquatic organisms. It synchronizes and accelerates fish and shrimp larvae growth on early developmental stages, as well as increases the development and size of these animals. In this work, the stimulating effect of Acuabio 1 on the immune system of Litopennaeus vannamei shrimps was demonstrated by obtaining (5.4 x 106 hemocytes/mL greater than the control group (4.3 x 106 hemocytes /mL). The hemolymph of treated animals showed higher lectin titers (16) than the control group (8). Animals treated with Acuabio 1 increased their phenoloxidase and peroxidase activities, indicating an enhanced oxidative defense. Furthermore, Acuabio 1 decreased the number of Vibrio spp and Pseudomonas spp. colony forming units in the culture medium, suggesting a possible prebiotic function. All these properties make Acuabio 1 very attractive to improve the production, survival rate and quality of shrimp larvae. [ABSTRACT FROM AUTHOR]

Silver carp (Hypophthalmichthys molitrix) is not endemic to Cuba, and egg fertilization is totally artificial; males produce spermatozoa only between March and October. Cryopreservation of silver carp spermatozoa would reduce the number of males needed, minimize handling stress through less frequent stripping, and facilitate artificial propagation when eggs are available. The effects on motility and fry production from eggs fertilized with thawed sperm under farm-conditions were examined in this study. Five, seven and ten percent of dimethyl sulfoxide (DMSO), glycerol and methanol were tested as cryoprotectants. DMSO was a more suitable cryoprotectant than methanol or glycerol. The effect of equilibration time on the motility rate at 10% DMSO was evaluated. Hatching rates equal to the control (P>0.01) were obtained under farm conditions with frozen spermatozoa, stored even for a year in liquid nitrogen, with a final DMSO concentration of 10%. Cryopreservation offers a useful routine method for sperm storage and silver carp handling. To our knowledge, this is the first report on the production of fry from post-thaw silver carp spermatozoa under farming conditions. [Copyright &y& Elsevier]