Novel genotyping assay for the nt230 (del4) ABCB1 gene mutation and its allele frequency in Border Collie dogs in Mexico.

A 4-bp deletion in the ATP-binding cassette subfamily B member 1 (ABCB1) gene, also referred to as the multidrug resistance gene (MDR1), produces stop codons that cause premature termination of P-glycoprotein 1 (P-gp) synthesis. Dogs with the homozygous mutation do not express functional P-gp, which increases their sensitivity markedly to many common veterinary drugs. We detected the nt230 (del4) ABCB1 mutation in Border Collie dogs in western Mexico with a simple and affordable primer-introduced restriction analysis PCR (PIRA-PCR). PIRA-PCR clearly identified all genotypes in our sample of 104 dogs. Genotype frequencies were 0.952 (wild/wild), 0.029 (wild/mut) and 0.019 (mut/mut). Allele frequencies were 0.033 (mutant alleles) and 0.966 (wild-type alleles). In this small subset of the Mexican dog population, we found a higher prevalence of the nt230 (del4) MDR1/ABCB1 gene mutation than reported in other countries.

pirA- and pirB-like gene identification in Micrococcus luteus strains in Mexico.

Acute hepatopancreatic necrosis disease (AHPND) was first reported in China in 2009 and afterwards in Mexico in 2013. AHPND is caused by Vibrio parahaemolyticus and affects Penaeus monodon and Litopenaeus vannamei shrimp cultures. The bacterium contains the pirA- and pirB-like genes in 69- to 70-Kb plasmids, which encode the toxins that produce the disease. The aim of this study was to determine whether pirA- and pirB-like genes existed in bacterial genera distinct from Vibrio before the first cases of AHPND were documented in Mexico. Two bacterial isolates were selected from shrimp farms in Nayarit in 2006 and analysed by nested-PCR to determine the presence of pirA- and pirB-like genes. The two isolates chosen did indeed show the presence of these genes, and those findings were confirmed by sequencing. Both strains matched to the bacterial species Micrococcus luteus. Results revealed two important situations: (a) the pirA- and pirB-like genes were present in a bacterial species that has not been reported previously (Micrococcus luteus); and (b) pirA- and pirB-like bacterial genes were present in Mexico before the first AHPND outbreak was reported in China.

Enhancing gilthead seabream immune status and protection against bacterial challenge by means of antigens derived from Vibrio parahaemolyticus.

In an attempt to control the proliferation of the pathogenic bacterium Vibrio parahaemolyticus in gilthead seabream (Sparus aurata), the immunostimulant effect of lysate and ToxA from this bacterium was evaluated. Fish were intraperitoneally injected twice (first injection, day 1 of the experiment; second injection, day 7) and sampled after one week (on days 8 and 15). Afterwards, all fish specimens were experimentally infected with V. parahaemolyticus and mortality was recovered for 1 week. Fish injected with lysate, ToxA and phosphate buffer saline (control) showed 100%, 50% and 0% survival, respectively, when challenged with the pathogen. Skin mucus immune parameters and immune-related gene expression in skin and spleen were also evaluated. The results showed that mucus immune parameters were enhanced in the lysate and ToxA groups compared with the values obtained for fish from the control group. Expression of IL-1ß, TNF-α, C3 and IgM genes was significantly up-regulated in the lysate and ToxA groups, principally after infection with the bacterium. Interestingly, TLR5 gene expression increased in fish immunized with lysate. The most prominent histological characteristic in gut from infected fish was the presence of a great number of intraepithelial leucocytes as well as inflammation of the submucosa, while severe hydropic degeneration and hemosiderosis were detected in liver from infected fish. Injection of lysate or ToxA had a protective effect against the deleterious consequences of subsequent infection with V. parahaemolyticus in gut and liver. The findings underline the potential of lysate and ToxA as potent preventive antigens against this kind of vibriosis.

Genotyping of friesian horses to detect a hydrocephalus-associated c.1423C>T mutation in B3GALNT2 using PCR-RFLP and PCR-PIRA methods: Frequency in stallion horses in México.

Hydrocephalus in Friesian horses is an autosomal recessive hereditary disease that can result in an abortion, a stillbirth, or euthanization of a newborn foal. Here, the hydrocephalus-associated c.1423C > T mutation in B3GALNT2 gene was detected with PCR-RFLP and PCR-PIRA methods for horse genotyping. A preliminary genotyping survey was performed on 83 randomly selected Friesian stallion horses to determine the current allele frequency in Mexico. The frequency of the mutant T allele was 9.6%.

Bioconcentración de elementos minerales en Amaranthus Dubius (bledo, pira), creciendo silvestre en cultivos del Estado Miranda, Venezuela, y utilizado en alimentación / Bioconcentration of mineral elements in Amaranthus Dubius (wild spinach, imbuya) growing wild in crops from Miranda State, Venezuela, and used as food / Bioconcentração de elementos minerais em Amaranthus Dubius (bredo, caruru), crescendo silvestre em cultivos do Estado Miranda, Venezuela, e utilizado na alimentação

El objetivo de este trabajo fue evaluar en la especie Amaranthus dubius el factor de bioconcentración (FB) de nutrientes minerales y metales no esenciales, dada por el cociente entre su concentración en los órganos aéreos y la de los respectivos suelos, en muestras colectadas en tres sitios del Estado Miranda, Venezuela: El Jarillo, la Escuela Técnica Agropecuaria Carrizal y La Maitana. También se comparó el FB con el de otras seis especies, entre ellas A. hybridus. Se encontró que en las dos especies de amaranto el FB de K fue mayor y se observó bioconcentración de N, P, K, Mg, Ca y Cd en sus hojas; sin embargo, para Al, Fe, Mn, Cu, Ni, Zn, Co, Cr y Pb se obtuvo un FB<1. En Carrizal se hizo un segundo muestreo, colectando las raíces, comparándose A. dubius con tallos verdes o rojizos, y no se encontraron diferencias en la composición elemental en plantas de diferente coloración. Las hojas presentaron mayor concentración que las raíces para N, P, K, Ca, Mg, Mn, Cu y Zn (factor de transferencia, FT>1). A. dubius resultó muy rico en N, P, K, Ca, Mg, Fe y Zn, elementos que interesan en la dieta animal, obteniéndose valores mayores en las hojas en comparación con las inflorescencias; sin embargo, se alerta sobre la necesidad de un control de los elementos no esenciales que pueden presentarse en concentraciones no recomendadas para el consumo, tal como ocurrió con Cd, Al, Cr y Pb en las muestras colectadas.

The goal of the present work was to evaluate in the species Amaranthus dubius the bioconcentration factor (BF) of mineral nutrients and non essential metals, calculated as the ratio of the concentration of them in the aerial organs to that in the soil, in samples collected from three sites in Miranda State, Venezuela: El Jarillo, the Agrarian Technical School Carrizal and La Maitana. The BF obtained was compared with that of six other species, including A. hybridus. It was found that in both amaranth species the BF of K was higher than in the other species, and bioconcentration of N, P, K, Mg, Ca and Cd in their leaves was observed; however, a BF<1 was found for Al, Fe, Mn, Cu, Ni, Zn, Co, Cr and Pb. The sampling was repeated in Carrizal, collecting roots and comparing A. dubius with green or red stems. No differences in the elemental composition were found in plants of different color. Leaves were more concentrated in N, P, K, Ca, Mg, Mn, Cu y Zn than roots (translocation or transfer factor, TF>1). A. dubius contained high levels of N, K, Ca, Mg, Fe and Zn, essential elements in the animal diet, with higher values in leaves than in flowers. However, control of the non essential elements that can be in inadequate concentrations to be consumed as food is necessary, as is the case for Cd, Al, Cr, Ni and Pb in the collected samples.

O objetivo deste trabalho foi avaliar na espécie Amaranthus dubius o fator de bioconcentração (FB) de nutrientes minerais e metais não essenciais, dada pelo cosciente entre sua concentração nos orgãos aéreos e a dos respectivos solos, em amostras coletadas en três lugares do Estado Miranda, Venezuela: El Jarillo, a Escola Técnica Agropecuaria Carrizal e La Maitana. Também foi comparado o FB com o de outras seis espécies, entre elas A. hybridus. Encontrou-se que nas duas espécies de amaranto o FB de K foi maior e se observou bioconcentração de N, P, K, Mg, Ca e Cd em suas folhas; no entanto, para Al, Fe, Mn, Cu, Ni, Zn, Co, Cr e Pb se obteve um FB<1. Em Carrizal foi realizada uma segunda amostragem, coletando as raízes, comparando-se A. dubius con caules verdes ou avermelhados, não encontrando diferenças na composição elemental em plantas de diferente coloração. As folhas apresentaram maior concentração que as raízes para N, P, K, Ca, Mg, Mn, Cu e Zn (fator de transferência, FT>1). A. dubius resultou muito rico em N, P, K, Ca, Mg, Fe e Zn, elementos que interessam na dieta animal, obtendo-se valores maiores nas folhas em comparação com as inflorescências; no entanto, se alerta sobre a necessidade de um controle dos elementos não essenciais que podem apresentar-se em concentrações não recomendadas para o consumo, tal como ocorreu com Cd, Al, Cr e Pb nas amostras coletadas.