Time filter

Source Type

PubMed | Technological Institute of the Llano de Aguascalientes, Livestock Health and Production Institute ULE CSIC and Complutense University of Madrid
Type: | Journal: Veterinary parasitology | Year: 2016

The cyst-forming protozoan parasite Neospora caninum is one of the main causes of bovine abortion worldwide and is of great economic importance in the cattle industry. Recent studies have revealed extensive genetic variation among N. caninum isolates based on multilocus microsatellite genotyping. Currently, the most extensive study reported is based on the N. caninum genotyping of 96 samples from four countries on two continents (Spain, Argentina, Germany and Scotland) that demonstrate different clusters of multilocus genotypes (MLGs) implicated in cattle abortions as well as the population sub-structuring of N. caninum, which is partially associated with the geographical origin. The aim of this study was to genotype N. caninum from aborted bovine foetuses that originated from Mexico within the region of Aguascalientes and to investigate their genetic diversity. Parasite DNA was detected in 27 out of the 63 analysed foetuses recovered from 10 different herds. Complete or nearly complete profiles based on 9 microsatellite markers were obtained from 11 samples. Diverse N. caninum MLGs were implicated in the occurrence of abortion in each herd. All of the Mexican MLGs differed from the MLGs previously determined for the Argentinean, Spanish, German and Scottish N. caninum populations. The Mexican MLGs failed to cluster by eBURST analyses. The MLG relationships using PCoA showed a close genetic relationship between the Spanish population and a portion of the Mexican population, but a more distant genetic relationship with the Argentinean genotypes. These results demonstrate the genetic diversity of N. caninum in the studied areas that differed from other populations of N. caninum around the world.


PubMed | Technological Institute of the Llano de Aguascalientes and Autonomous University of the State of Morelos
Type: Journal Article | Journal: Journal of dairy science | Year: 2016

The aim of this study was conducted to evaluate the effect of natural infestation by Stomoxys calcitrans on the behavioral and adrenocortical responses of dairy cattle. Twenty Holstein cows randomly selected were individually sprayed with insecticide once every 7d, whereas no insecticide was applied to the other 20 animals. The average number of flies per cow was estimated daily, and the frequency of fly-avoidance behaviors was measured daily; plasma cortisol concentration was measured each morning. No flies were ever counted on the treated cows at any time during the experiment, whereas an average of 17.131.14 (standard error) flies/d were recorded on untreated cows. Tail movement was the most frequent behavior displayed, with stamps or kicks showing the highest increment rate (41.2) when fly population increased from zero to greater than 51 flies/cow. Cortisol concentration increased to a maximum of 56.8139.53ng/mL with 26 to 30 flies/cow per day. Coefficients of determination between the number of flies, cortisol concentration, tail movements, and stamps or kicks were 0.73, 0.78, and 0.81, respectively. The multiple correlation coefficient was 0.90, with 81% of the variation in cortisol concentration explainable by variation in the number of flies per cow and the frequency of fly-avoidance behaviors. It was concluded that plasma cortisol concentration is linearly related to a combination of the number of flies and the frequency of fly-dislodging behaviors, producing a maximum response before reaching maximum fly loads.


Romero-Salas D.,University of Veracruz | Garcia-Vazquez Z.,National Research Center Disciplinaria en Parasitologia Veterinaria | Montiel-Palacios F.,University of Veracruz | Montiel-Pena T.,University of Veracruz | And 3 more authors.
Journal of Animal and Veterinary Advances | Year: 2010

The objective of this study was to determine the seroprevalence of Neospora caninum antibodies in 863 female cattle 1 to ≥6 years old from 78 herds of dairy, beef and crossbred cattle in Veracruz, Mexico. Serum samples were tested for the presence of N. caninum antibodies using an ELISA assay. Overall seroprevalence of N. caninum antibodies was 26%. By municipality, the highest prevalence was 47.4% and the lowest 6% (p<0.05). By age, the highest prevalence was found in 5 year olds (28%) and the lowest (11.1 %) in 1 year olds (p<0.05). Regarding the breed, the highest seroprevalence was observed in crossbred females (p<0.05). Considering the reproductive status, the highest seroprevalence was in cows with >5 calvings (32.1 %) and the lowest was in pubertal heifers (11.1%; p<0.05). Seroprevalence was 26.2% in homebred and 23% in purchased animals (p>0.05). Prevalence in females with a history of abortions was 40 and 26.2% in females with no records of previous abortions (p<0.05). The results show that bovine neosporosis is widespread in the State of Veracruz, Mexico, as in other regions of the country. © Medwell Journals, 2010.


Ojeda-Chi M.M.,Autonomous University of Yucatán | Rodriguez-Vivas R.I.,Autonomous University of Yucatán | Galindo-Velasco E.,University of Colima | Lezama-Gutierrez R.,University of Colima | Cruz-Vazquez C.,Technological Institute of the Llano de Aguascalientes
Revista Mexicana De Ciencias Pecuarias | Year: 2011

Infestations with cattle tick, Rhipicephalus microplus constitute the most important ectoparasite problem in the tropical and subtropical regions of the globe, resulting in major economic losses in the production of beef, milk, and leathers, in addition of increasing the cost of control programs transmitting Babesia bovis, B. bigemina and Anaplasma marginale. The control of R. microplus is mostly based on the use of ixodicides. Nevertheless, the irrational use of such products has resulted in tick populations exhibiting resistance to all major ixodicide drug classes. This has urged the development of non-chemical control alternatives, including the use of entomopathogenic fungi, among which Metarhizium anisopliae (Hypocreales: Clavicipitaceae) has shown to be efficient both in vitro and in vivo for the control of the different evolution stages of R. microplus. The use of these fungi results in decreased oviposition, increased incubation/hatch times, and death of tick larval and adult stages, with efficiency rates of up to 100 %. Several studies show that M. anisopliae is a sustainable non-chemical alternative for the control of ticks. The purpose of this paper is to present an updated review on the use of different M. anisopliae strains for the control of R. microplus.


Velarde Martinez A.,Technological Institute of the Llano de Aguascalientes | Luna Ramirez E.,Technological Institute of the Llano de Aguascalientes | Soria Cruz J.,Technological Institute of the Llano de Aguascalientes | Ponce de Leon Senti E.,Autonomous University of Aguascalientes
Ingeniare | Year: 2016

In this paper, it is proposed a method to carry out an evaluation of the objectives that may conflict during the task planning and assignment task in a two-mesh multicomputer system, which includes the evaluation of the waiting, processing and transfer times of tasks. In the first instance, the proposed method uses two algorithms: an assignment algorithm for detecting the free processors in a mesh and a dynamic algorithm for selecting the tasks in a waiting queue that is susceptible to be assigned to the free objective system processors. To select the processors a set of tasks will be assigned, this method uses additionally a distribution estimation algorithm for determining which processors offer the best assignment solution respect to the impact of the evaluated objectives in the system performance. The results obtained withthe proposed method showed an improvement in the waiting task and processing times compared to the results produced by task assignment techniques such as the lineal technique and the Hilbert curves. © 2016, Universidad de Tarapaca. All rights reserved.


Galindo-Velasco E.,University of Colima | Lezama-Gutierrez R.,University of Colima | Cruz-Vazquez C.,Technological Institute of the Llano de Aguascalientes | Pescador-Rubio A.,University of Colima | And 4 more authors.
Veterinary Parasitology | Year: 2015

The purpose of this paper is to evaluate the effect of five strains of Metarhizium anisopliae (Ma) and three strains of Isaria fumosorosea (Ifr) at a concentration of 1 × 108colonyformingunits/ml applied by spraying onto bovines with controlled infestation of Haematobia irritans under stable conditions in the Mexican dry tropics. Four experiments were performed, in each of which three treatments (two fungal strains and one control) were evaluated with eight repetitions for each one, by carrying out a single application of the aqueous suspension of each strain. The animals were isolated in individual cages and direct counts of the infestation were carried out for 13 days. It was observed that strains Ma2, Ma6, Ma10, Ma14, and Ma34 caused 94-100% reduction in infestation between days 12 and 13 post-treatment, while strains Ifr19, Ifr11, and Ifr12 reduced infestation from 90% to 98% up to day 13 post-application. There was an effect in the generation of horn flies from the excrement of bovines that were treated with different strains, reducing the reproduction of subsequent generations. It was concluded that the strains of M. anisopliae and I. fumosorosea evaluated in this study can be used as biocontrol agents in infestations of H. irritans in stabled bovines. © 2015 Elsevier B.V.


Lopez-Sanchez J.,Technological Institute of the Llano de Aguascalientes | Cruz-Vazquez C.,Technological Institute of the Llano de Aguascalientes | Lezama-Gutierrez R.,University of Colima | Ramos-Parra M.,Technological Institute of the Llano de Aguascalientes
Biocontrol Science and Technology | Year: 2012

The pathogenicity and virulence of 10 isolates of entomopathogenic fungi from the soil of lodging pens of dairy production units in Aguascalientes, Mexico, on adults of Stomoxys calcitrans and Musca domestica were determined. All isolates were pathogenic when exposed by aspersion to a concentration of 1×108 conidia/ml, causing between 20.3 and 91.7% mortality in S. calcitrans and between 31 and 91.7% in M. domestica at 7 days post-exposure; in S. calcitrans isolates of Beauveria bassiana (Bb114) and Metarhizium anisopliae (Ma135), sensu lato, were the most noteworthy as mortality reached above 90% with an LC50 of 3.5×105 conidia/ml for Bb114, while for Ma135 reached 1.6×104 conidia/ml. In M. domestica Ma134 and Ma135 showed mortality above 90% with an LC50 of 4.3×104 and 1.4×105 conidia/ml, respectively. © 2012 Copyright Taylor and Francis Group, LLC.


Zapata-Vazquez A.,Technological Institute of the Llano de Aguascalientes
TheScientificWorldJournal | Year: 2012

Chili pepper blight observed on pepper farms from north Aguascalientes was monitored for the presence of Phytophthora capsici during 2008-2010. Initially, ELISA tests were directed to plant samples from greenhouses and rustic nurseries, showing an 86% of positive samples. Later, samples of wilted plants from the farms during the first survey were tested with ELISA. The subsequent survey on soil samples included mycelia isolation and PCR amplification of a 560 bp fragment of ITS-specific DNA sequence of P. capsici. Data was analyzed according to four geographical areas defined by coordinates to ease the dispersal assessment. In general, one-third of the samples from surveyed fields contained P. capsici, inferring that this may be the pathogen responsible of the observed wilt. Nevertheless, only five sites from a total of 92 were consistently negative to P. capsici. The presence of this pathogen was detected through ELISA and confirmed through PCR. The other two-thirds of the negative samples may be attributable to Fusarium and Rhizoctonia, both isolated instead of Phytophthora in these areas. Due to these striking results, this information would be of interest for local plant protection committees and farmers to avoid further dispersal of pathogens to new lands.


PubMed | University of Guanajuato, Technological Institute of the Llano de Aguascalientes, University of Colima and Autonomous University of Yucatán
Type: Journal Article | Journal: Veterinary parasitology | Year: 2015

The purpose of this paper is to evaluate the effect of five strains of Metarhizium anisopliae (Ma) and three strains of Isaria fumosorosea (Ifr) at a concentration of 110(8)colony-forming units/ml applied by spraying onto bovines with controlled infestation of Haematobia irritans under stable conditions in the Mexican dry tropics. Four experiments were performed, in each of which three treatments (two fungal strains and one control) were evaluated with eight repetitions for each one, by carrying out a single application of the aqueous suspension of each strain. The animals were isolated in individual cages and direct counts of the infestation were carried out for 13 days. It was observed that strains Ma2, Ma6, Ma10, Ma14, and Ma34 caused 94-100% reduction in infestation between days 12 and 13 post-treatment, while strains Ifr19, Ifr11, and Ifr12 reduced infestation from 90% to 98% up to day 13 post-application. There was an effect in the generation of horn flies from the excrement of bovines that were treated with different strains, reducing the reproduction of subsequent generations. It was concluded that the strains of M. anisopliae and I. fumosorosea evaluated in this study can be used as biocontrol agents in infestations of H. irritans in stabled bovines.


Castaneda-Hernandez A.,Technological Institute of the Llano de Aguascalientes | Cruz-Vazquez C.,Technological Institute of the Llano de Aguascalientes | Medina-Esparza L.,Technological Institute of the Llano de Aguascalientes
Small Ruminant Research | Year: 2014

The purpose of this study was to determine the seroprevalence of anti-. Neospora caninum antibodies, the prevalence of the parasite's DNA in blood and to estimate the association between seroprevalence and potential risk factors in sheep herds in Aguascalientes, Mexico. A total of 324 blood samples were taken from 13 farms and tested using ELISA in order to detect N. caninum antibodies and nested PCR was used to determine the prevalence of the parasite's DNA in blood. The association between seroprevalence and some potential risk factors was estimated. The general seroprevalence reached 5.5% (18/324; 95% C.I. 3-8), ranging between 4 and 15% with the presence of seropositive animals in 61.5% of the farms; seroprevalence in ewes was 5.2% (15/286; 95% C.I. 3-8) while in rams it reached 7.9% (3/38; 95% C.I. 2-22). The prevalence of the parasite's DNA in blood was 25% (81/324; 95% C.I. 20-30), with a range from 7.7 to 50%, with 84.6% of the flock with at least one positive animal. Were identified as positive to both tests the 3% of the animals probed (10/324; 95% C.I. 1-5) of which nine were ewes and only one ram. The agreement between tests was k= 0.12. No association statistically significant was found between seroprevalence and the risk factors considered in this study. © 2014 Elsevier B.V.

Loading Technological Institute of the Llano de Aguascalientes collaborators
Loading Technological Institute of the Llano de Aguascalientes collaborators