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Copyright of Revista de Biologia Marina y Oceanografía (RBMO) is the property of Universidad de Valparaiso, Facultad de Ciencias del Mar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Biologia Marina y Oceanografía (RBMO) is the property of Universidad de Valparaiso, Facultad de Ciencias del Mar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The presence of diseases caused by virus and bacteria pose a threat to the capture and commercialization of shrimp, and may cause significant economic damage. Nocturnal monthly sampling were conducted to detect the presence of IHHNV, WSSV, and NHP in San Andres Lagoon in Tamaulipas, Mexico, an important coastal ecosystem due to its shrimp fishery and the existence of shrimp farms in the area. Polymerase chain reaction (PCR) analysis in the shrimp tissue did not detect the presence of IHHNV, however, WSSV was detected, as well as NHP during July and August, when low salinities and high temperatures were recorded. [ABSTRACT FROM AUTHOR]

Copyright of Veterinaria México is the property of Facultad de Medicina Veterinaria y Zootecnia UNAM and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A 3-year-old male Bloodhound dog was presented to a private veterinary hospital at Ciudad Victoria, Tamaulipas, Mexico, with a 2-week history of weight loss, generalized weakness, anorexia and ptyalism. Results of a hemogram revealed moderate anemia with a chronic inflammatory leukogram. Also, various neutrophlis (approximately 10%) containing elongated pale blue staining intracytoplasmic inclusions, compatible with gametocytes of Hepatozoon spp were observed. Up until now, this is the first case report of canine hepatozoonosis detected in Tamaulipas. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the pathogenicity and infection pathway of Vibrio parahaemolyticus in American white shrimp or Litopenaeus vannamei. For the study, researchers analyzed Vibrio parahaemolyticus from the collection of aquatic microorganisms. They found that shrimp infected with Vibrio parahaemolyticus demonstrated symptoms of disease similar to those previously examined in juvenile shrimp infected with Vibrio.

The article discusses the detection of channel catfish virus (CCV) associated with mortality of cultured channel catfish in Mexico. The good quality of channel catfish' flesh and flavor has resulted the increase catfish consumption and growing fish farming industry. However, the detection of Herpesvirus ictaluri CCV was first isolated in the U.S. in 1960 that led the high mortality rates with significant economic losses of catfish industry. The histophathological examination has revealed multifocal necrotic areas and hemorrhage in the internal organs with viral infection.The CCV's infection is the most severe of the fish herpesvirus which proliferation was caused by stressful environmental conditions such as high temperature, low water quality, low oxygen level and poor feeding.

Shrimp is one of the main aquaculture species in the world. Different viruses affect them, which causes serious mortality to economically important species, such as Penaeus monodon, Litopenaeus vannamei and L. stylirostris, among others. White spot syndrome virus or WSSV is a highly lethal, stress-dependent virus, which belongs to the family Nimaviridae, genus Whispovirus. Three WSSV virus isolates were first detected in 1992 in Thailand, Taiwan and China. Later, a fourth isolate of the virus was detected in the Americas in 1999. This virus has a large circular double-stranded DNA genome with different sizes (292.9–307.2 kb), where the diverse isolates show differences in virulence. This virus infects a wide range of aquatic crustaceans by vertical and horizontal transmission, with different mortality results. The spread of infection between regions may be due to infected shrimp and carriers such as other crustaceans, seabirds, aquatic arthropods or other vectors. The aim of this work is to describe the current knowledge on the status, transmission, pathology, isolation, control and genomic characteristics of WSSV. [ABSTRACT FROM AUTHOR]

Shrimp aquaculture is an important industry that experiences significant losses fromVibriospecies, especially at the larval and juvenile stages. Proteinaceous virulence factors, including alkaline proteases, metalloproteases, cysteine proteases and alkaline serine proteases, have been identified as important elements inVibriopathogenesis. This review summarizes current knowledge regarding the principal pathogenicVibriospecies in shrimp, with emphasis on relevant exotoxins and their modes of action, principal characteristics and molecular database. This pathogenic factors and their relation with other molecules produced by microorganisms may be help to understand the virulence mechanisms present inVibriostrain. [ABSTRACT FROM AUTHOR]

Baker''s yeast Saccharomyces cerevisiae is a potential supplement in shrimp feeds, but there are few data on yeast survival after feed manufacturing processes. Dry, active yeast cells, agglomerated in spheres of different sizes (100–200 and 800–1600 μm) were incorporated into feeds processed by a commercial pellet mill or in the laboratory using a meat grinder, in order to check their resistance to the process, storage, immersion in seawater, and their effect on the pellet stability in seawater. Total counts (cells seen alive by microscopy evaluation) and viable yeast counts (colony forming units on malt agar plates) were determined in feed samples at different stages of the process. Pelleting had no significant effect on total yeast counts but decreased the viable yeast numbers about 10-fold. The laboratory process was more destructive with a 105-fold decrease for both total and viable yeast counts. Immersing the feed pellets in seawater further reduced the yeast number but only by less than 10-fold. Fine yeast spheres (<200 μm) had a slightly better overall resistance and survival than large yeast spheres (>800 μm). Pellet stability in seawater was not affected by the inclusion of the yeast agglomerates. [Copyright &y& Elsevier]

Equisetum myriochaetum is a semi-aquatic plant found on riverbanks that is commonly used in traditional medicine as a diuretic agent. Additionally, the genus Equisetum stands out for its content of the flavonoid kaempferol, a well-known antiproliferative agent. Therefore, in this study, E. myriochaetum ethanolic extract was tested in vitro against a cervical cancer cell line (SiHa). Additionally, the antioxidative activity was evaluated through a 2,2-diphenyl-1-picrilhidrazil (DPPH) assay. Finally, a molecular docking analysis of apigenin, kaempferol, and quercetin on the active site of β-tubulin was performed to investigate their potential mechanism of action. All fractions of E. myriochaetum ethanolic extract showed antioxidative activity. Fraction 14 displayed an antiproliferative capacity with a half maximal inhibitory concentration (IC50) value of 6.78 μg/mL against SiHa cells. [ABSTRACT FROM AUTHOR]

The inclusion of Yucca schidigera and Quillaja saponaria extracts (NTF) in aquatic organisms display a positive response on production and organism's physiology. Fifteen tanks (140 L) with low-salinity water (S = 5) were stocked with 10 juvenile shrimp (Litopenaeus vannamei, 2.6 g of mean weight) feeding with 0, 0.25, 0.5, 1.0 and 2.0 g kg-1 of NTF of basal diet (triplicate treatment). The shrimp were cultured in a close recirculation system (control condition) and fed ad libitum daily for 40 days. General growth parameters (body weight, growth, body length, feed conversion rate, survival) and hepatopancreatic digestive enzyme activities (alkaline protease, alkaline phosphatase, α-amylase, leucine aminopeptidase, and lipase) were evaluated after 40 days of shrimp culture. The final mean body weight, individual mean body, weight gain, and feed conversion ratio from shrimp feeding with 1.0 and 2.0 g kg-1 of NTF have a significant (P < 0.05) result compared to other treatments. The highest values of alkaline protease, lipase, and α-amylase were detected in shrimp feeding with 0.5 g kg-1 of NTF, where a high level of leucine aminopeptidase and alkaline phosphatase were detected with 0.25 g kg-1 of NTF treatment. However, any significant differences in enzyme activities were detected between the control group and treatments. The increase effect in shrimp growth and any decrease effect in enzyme activity detected in present study suggest that NTF shows potential as a feed additive for shrimp cultured at low-salinity. [ABSTRACT FROM AUTHOR]

In February 2012, a reproductive group of 60 adult blackbucks (Antilope cervicapra) from Veracruz, Mexico was relocated to hunting units in eastern and northeastern Mexico. Seven individuals died due to hemorrhagic parasitic, abomasitis and enteritis caused by Haemonchus spp., Setaria spp., and Trichostrongylids. Deaths were associated with hepatic necrosis, bilateral congestive distention of heart and fibrinonecrotic bronchopneumonia. Also Anaplasma marginale was identified. The blackbucks' population displayed a general mortality rate of 11.67%, where 25% of total male and 9.62% of total female died. The mortality was controlled by segregation of all remaining blackbucks and the treatment for internal and external parasites (biting flies and ticks). After the treatment, no fatality cases related to parasitosis were recorded. The results presented here exhibit the high relevance of parasitosis as possible factor risk in the survival of tis specie. [ABSTRACT FROM AUTHOR]

Diseases are of particular importance for aquaculture worldwide, particularly in intensive culture. In Mexico, intensive culture of channel catfish is mainly done in floating cages. The aim of the present study was to determine the presence of the myxozoan Henneguya and the effect of site, period and host length on its prevalence in cage-cultured channel catfish. Over a year, fish were examined on six different sites. Results showed the presence of Henneguya exilis in all the farms. However, no significant effects were observed for site and season on prevalence, nor was there a correlation between host length and infection prevalence [ABSTRACT FROM AUTHOR]

Bioassays were carried out in a closed system to evaluate the susceptibility of Litopenaeus schmitti and Cherax quadricarinatus to white spot syndrome virus (WSSV) using L. vannamei as the positive control reference species. Animals were injected intramuscularly (20 μL shrimp-1) with a WSSV preparation obtained from the Aquaculture Pathology Laboratory of the University of Arizona. These infected organisms were reared separately in their respective experimental tank. Susceptibility to WSSV was significantly greater in L. vannamei than in the other two species (P < 0.05). The histological analysis showed characteristic inclusion bodies of WSSV in these three crustacean species, with a different distribution of infection depending on the tissue and species. In situ hybridization also showed these signs of infection in hemocytes and hepatopancreas. [ABSTRACT FROM AUTHOR]

Disease control problems have major constraints in aquaculture production, and the use of probiotics in larviculture is a valid alternative to antibiotics. This study analyzed the effect of probiotic bacteria on survival and final size of Cortez oyster larvae Crassostrea corteziensis. Two different probiotic concentrations were evaluated, 1 x 10(4) and 1 x 10(5) CFU/ml of Lactic acid bacteria (strain NS61) isolated from Nodipecten subnodosus, and bacilli isolated from the white leg shrimp, Litopenaeus vannamei (Pseudomonas aeruginosa, strain YC58) and C. corteziensis (Burkholderia cepacia, strain Y021). Bacteria were added directly into culture tanks, starting the bioassays from veliger to pediveliger stages as follows: (1) Control, without probiotics; (2) lactic acid bacteria (Lb); (3) bacilli mix (Mb) in a proportion 1:1. Results showed a higher larval survival with Lb and Mb at a dose of 1 x 10(4) CFU/ml compared to the control group. Larvae exposed to Mb at 1 x 10(5) CFU/ml showed higher survival than Lb and control. Larval final size was not significantly increased with the tested probiotics, but larvae treated with Lb at 1 x 10(5) CFU/ml showed less survival rate than those treated at 1 x 10(4) CFU/ml. This study showed the beneficial effect of these probiotics, added individually or mixed in C. corteziensis larvae culture.

The pathogenicity of Vibrio penaeicida Strains KH-1 and AM101, their culture-free supernatant (CFS), and their protein fraction obtained by 40% of ammonium sulfate precipitation (PFs40) were assessed in experimental challenges against juvenile Litopenaeus vannamei. Live Vibrio cells, CFS, and PFs40 from the AM101 strain produced a significantly higher mortality (p < 0.05) compared to the KH-1 strain. Toxicity and median lethal doses (LD50) of Fast Protein Liquid Chromatography (FPLC) products were evaluated on L. vannamei. The first FPLC fraction sample (A) from PFs40 of the AM101 strain displayed LD50 values of 1.68 and 5.61 microg protein ind.(-1), respectively. The second FPLC process from Fraction A showed a peak (A1) also with toxic effects to shrimp. PFs40, Fraction A, and Peak A1 showed a 38.5 kDa molecular band (SDS-PAGE), with activity on a gelatin protease zymogram. The lethal effect of PFs40 and Fraction A was inhibited by Proteinase K, CuCl2, E-64, and heat (60 and 100 degrees C) treatments, but was not inhibited by EDTA-Na2, aprotinin, and soy trypsin treatments. These results and the zymogram inhibition test suggest the presence of a cysteine protease-like proteinaceous exotoxin as a dominant protease, secreted by V. penaeicida Strain AM101.