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1.
BMC Vet Res ; 20(1): 326, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39026327

RESUMO

To evaluate Tribulus terrestris and Mucuna pruriens for inducing all-male tilapia, mixed-sex Nile tilapia, Oreochromis niloticus, (mean weight 0.025 ± 0.009 g; mean length 1.25 ± 0.012 cm), were given a meal supplemented with either T. terrestris powder (commercial fish feed, 40% crude protein) (TT group), M. pruriens seed extract (MP group), MP + TT (mixed group), 17α-methyl testosterone (MT, control positive), or without supplements (control negative). The MP extracts significantly increased (P < 0.05) the final weight, weight gain, weight gain rate, and specific growth rate while feed conversion ratio was significantly decreased (P < 0.05). Plant extracts markedly improved (P < 0.05) the survival rate, proportion of males, and total testosterone compared to control and MT. Estrogen levels were lower in groups with plant extract than other groups. Fifteen days post-feeding, the Amh gene was expressed in the brain of O. niloticus fries with higher levels in MP, TT, and MT groups. Additionally, the expression of the Sox9 and Dmrt1 genes as a male related genes in fish fry gonads revealed significantly (P < 0.05) higher levels in groups fed on MP, TT, and MT compared to control after 30-day post-feeding, whereas; Foxl2 gene expression as a female related gene was significantly (P < 0.05) lower in fish fed on MP, TT, and MT compared to other groups after 30 days post feeding. Histologically, MT, MP, TT, and the mixture all exhibited solely male reproductive traits without noticeable abnormalities. This study concluded that each of the TT or MP extracts can induce sex reversal in tilapia while having no negative health impact compared to MT as the growth and survival rate in the treated groups with TT and MP were higher than control and group treated with MT.


Assuntos
Ração Animal , Ciclídeos , Suplementos Nutricionais , Metiltestosterona , Mucuna , Tribulus , Animais , Masculino , Tribulus/química , Metiltestosterona/farmacologia , Ração Animal/análise , Mucuna/química , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Dieta/veterinária , Proteína Forkhead Box L2/genética , Feminino , Testosterona/sangue
2.
Aquac Int ; 31(3): 1253-1267, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36439703

RESUMO

This study aimed to develop and evaluate live and inactivated vaccines to Aeromonas veronii pathogenicity in Nile tilapia. Therefore, five well-identified Aeromonas veronii isolates, including A (HY1), A (HY2), A (HY3), A (HY4), and A (HY6) isolated from diseased Nile tilapia (Oreochromis niloticus), were used for vaccine preparation. Virulence genes detected by a polymerase chain reaction (PCR) and lethal dose determination were conducted. Nile tilapia, each with a body weight of 25 ± 0.5 g were divided into six experimental groups (each of 20): T1 group (control), fish were injected with saline as a negative control, T2 group (formalin-killed vaccine) for the A (HY2) strain, T3 group ( formalized killed vaccine) for the A (HY4), T4 group (autoclaved vaccine) for the A (HY2), T5 group (autoclaved vaccine) for A (HY4), and T6 (live vaccine) for A (HY1), triplicate. At the end of the immunization period, all groups were challenged by A. veronii, A (HY2). Blood samples were drawn 21 days post-immunization and 3 days after the challenge test for antibody titer assay. The results showed that the pathogenicity of strains A (HY2) and A (HY4) was the strongest, as the lethality rates (LR) were 100% and 90%, respectively, whereas the pathogenicity was moderate for strains A (HY3) and A (HY6) (LR 60% for each). A (AY1) was the weakest strain as no dead fish was found for this strain. The presence of alt, act, aerolysin, lipase, and fla genes as the main cause of the pathogenesis. The best protective efficacy was obtained from the live vaccine, A (HY1) with a protective rate of about 94.12% (relative percentage of survival, RPS), compared to autoclaved killed vaccines and formalin-killed vaccines. Based on immunoglobulin estimation (IgM) and RPS%, our data concluded that A (HY1) live vaccine had the best vaccine prophylactic effect against the highly pathogenic strain A(HY2).

3.
Vet Res Commun ; 45(4): 223-241, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34283348

RESUMO

The aim of this study was to assess the impact of using rapeseed meal as a partial replacement for fish meal in the diet of farmed tilapia. We evaluated the effect of this replacement on growth performance, profitability, serum biomarkers, antioxidant status, gut morphology, and water quality. A total of 960 apparently healthy Oreochromis niloticus (O. niloticus) and Sarotherodon galilaeus (S. galilaeus) fingerlings were randomly distributed into four dietary treatment groups for each tilapia species (triplicate design, 120 fish/group, and 40 fish/replicate). The diets consumed by these groups were formulated to replace fish meal (FM) with rapeseed meal (RM) at 0%, 10%, 20%, and 30%, respectively, for 12 consecutive weeks. Results indicated that replacing RM in the diet of S. galilaeus (up to 20%) and O. niloticus (up to 10%) resulted in increased growth performance parameters, including final weight, weight gain, length, length gain, weight gain rate, and specific growth rate (SGR), and return parameters such as a total return and relative return compared to the control group. Moreover, an increase in RM up to 30% improved net profit and increased the mucosal length, intestinal villi length, and the number of goblet cells compared with results in its relative control groups. Additionally, we observed a significant increase in serum and liver AST and ALT with increased RM replacement. With respect to water parameters, we observed a significant difference in the ammonia levels, turbidity, and conductivity with the changes to the percentage of RM in the diets. As for the effect on each species, O. niloticus showed a more significant increase in all examined parameters compared to results in S. galilaeus. In summary, up to 10% RM can be used to replace FM without any adverse effects on the growth performance, profitability measures, intestinal morphometric analysis, or water quality.


Assuntos
Ração Animal/análise , Aquicultura/economia , Brassica napus/química , Ciclídeos/crescimento & desenvolvimento , Qualidade da Água , Animais , Ciclídeos/anatomia & histologia , Ciclídeos/sangue , Ciclídeos/metabolismo
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