Implicación del semental caprino en la agalaxia contagiosaepidemiología descriptiva y molecular

Abstract

Recent published studies on the contagious agalactia (CA) and especially the advances in the knowledge of their molecular epidemiology and analytical as well as the most relevant aspects that are to be studied in the future were discussed in the review by invitation asked us magazine The Veterinary Journal (Study 1). The doctoral thesis has mainly focused on studying the epidemiological implications of bucks on the CA. Within this field of study has evaluated first the distribution of the organism in ear asymptomatic carrier bucks in order to determine the existence of possible systemic infections. All these questions were developed in a second wok, by microbiological and molecular (PCR) study of naturally infected stallions (Study 2). Moreover was necessary to implement prevention strategies and monitoring them to contemplate the identification of asymptomatic carriers in insemination centers (Study 3). This model is based on sampling animals both candidates to enter the centers as those present in them. The high genetic value of some of the bucks infected, motivated the development of another experience evaluating the effectiveness of the use of antibiotic treatment with marbofloxacin for ear asymptomatic carriers bucks. In addition, were also considered the potential impact that this treatment might have on sperm quality of stallions affected (Study 4). http://www.google.com/url?source=transpromo&rs=rssf&q=//translate.google.com/community?source=all Finally, the survival of the major etiological agents of CA, Mycoplasma agalactiae (Ma) and Mycoplasma mycoides subsp capri (Mmc) was evaluated in the diluted semen. Previously it was necessary to develop a model of experimental contamination which to obtain valid and extrapolated to field conditions results (Article 5). This model allowed subsequently developing a experimental study to evaluate the survival of these species of mycoplasmas in diluted semen and ejaculate, and their impact on sperm quality (Study 6). OBJECTIVES FIRST: Perform a literature review where progress is exposed in the study of molecular and analytical epidemiology of contagious agalactia, control and approach future strategies in their research. SECOND: Study the distribution of Mycoplasma spp. in ear asymptomatic carriers bucks. THIRD: Develop a program of prevention and monitoring of caprine contagious agalactia in artificial insemination centers effective for detecting asymptomatic carrier bucks candidates to enter in the centers and present inside. FOURTH: To study the efficiency of systemic treatment with marbofloxacin to eliminate infection in naturally infected ear asymptomatic carriers bucks with Mycoplasma subsp. mycoides subsp. capri, evaluating its effect on sperm quality. FIFTH: Develop an experimental model for goat semen contamination with Mycoplasma spp., to evaluate its effect on the viability and motility sperm, as well as its impact on sperm quality under different conditions of carriage. http://www.google.com/url?source=transpromo&rs=rssf&q=//translate.google.com/community?source=all SIXTH: Evaluation of the Mycoplasma agalactiae and Mycoplasma mycoides subsp. capri viability in diluted semen and their impact on sperm quality. CONCLUSIONS FIRST Systemic distribution of M. agalactiae and Mycoplasma mycoides subsp capri is confirmed in naturally infected ear asymptomatic carriers bucks. SECOND The presence of Ma and Mmc in the respiratory, digestive and urogenital system of asymptomatic carriers can be a risk factor for CA transmission by related secretions. THIRD Has been determined for the first time the presence of Mycoplasma mycoides subsp. capri in semen of asymptomatic bucks. FOURTH The combined of ear canal swabs and semen samples for the diagnosis of mycoplasma associated with CA is a useful tool to monitor the presence of asymptomatic carriers bucks in insemination centers. FIFTH Marbobloxacin systemic treatment was ineffective to eliminate Mycoplasma mycoides subsp. capri ear infections of naturally infected bucks while affecting sperm quality. SIXTH The survival as infective dose of Mycoplasma agalactiae and Mycoplasma mycoides subsp. capri diluted semen for at least 150 minutes is a risk factor for venereal transmission. SEVENTH Under the conditions studied, the seminal dose decreases the viability of Mycoplasma agalactiae while ejaculated is a medium that favors their growth, suggesting that natural breeding can increase the possibilities of venereal transmission of caprine contagious agalactia regarding the use of artificial insemination.