49 research outputs found
Epidemiological evaluation of subclinical mastitis of dairy cows in Greece
ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗSubclinical mastitis, diagnosed by elevated somatic cell count (SCC) in milk, is an important monitoring parameter of dairy cows’ udder health, related to their productivity and welfare. The present retrospective study aims to evaluate the epidemiology of subclinical mastitis (SCM) among the 37 herds of the Holstein Association of Greece participating in the milk quality recording system “ΙΩ”, from the start of 2015 until the end of 2018. The herds’ inclusion criterion was the consistency of monthly SCC recording throughout at least one full year between 2015 and 2018, with a maximum interval of 61 days between two consecutive monthly SCC recordings. Twenty-six herds (8630 cows) in 2015, thirty herds (10763 cows) in 2016, thirty herds (10945 cows) in 2017 and twenty-six herds (9597 cows) in 2018 were included. The prevalence of SCM and chronic SCM, the incidence rate of new cases of SCM, as well as the average somatic cell score and bulk tank milk SCC were determined for each of the four years. The results indicate a progressive deterioration of udder health from the onset of the cow’s productive life until culling. A year-over-year increase in the number of cows with subclinical mastitis led to an overall SCM prevalence of 34.5%, chronic SCM prevalence of 26.9% and a bulk tank milk SCC of 463000 cells/mL, in 2018. The average somatic cell score, a base 2logarithm of individual cow’s SCC, was found persistently above the subclinical mastitis indicative cut-off in all four years, with a peak in 2018. At herd level, the incidence rate of new SCM cases was 12 new cases / 100 cows / month; the highest incidence rate was observed in the early lactation stage group (1-60 days-in-milk), in all four years, reaching a peak of 31 new cases / 100 cows / month, in 2018. In 2018, prevalence of heifers’ SCM and chronic SCM was23.4% and 16.9%, respectively. Despite the adequate average 305-days milk yield (9608 kg in 2018), the results were indicative of poor udder health status, pointed out by reduced duration of cows’ productive life (less than 3 lactations)and lower milk quality (elevated SCC). The severity and wide spreading of subclinical mastitis in Greek dairy herds highlights the necessity of a national mastitis control program, aiming to improve the productive efficacy, management decisions accuracy and quality of produced milk
Proper use and impact of ‘Computer Assisted Semen Analysis’ technique on semen evaluation of farm animals
Σκοπός της παρούσας ανασκόπησης είναι η παρουσίαση της λειτουργίας του αυτόματου αναλυτή σπέρματος υποβοηθούμενου από ηλεκτρονικό υπολογιστή (CASA) και των εφαρμογών του στον τομέα της αναπαραγωγής των παραγωγικών ζώων, ώστε να γίνει ευρέως αντιληπτή η συμβολή του ως εργαλείο πρόγνωσης της γονιμότητας των αρσενικών ζώων Παρατίθενται οι προϋποθέσεις ορθής λειτουργίας του αναλυτή, οι παράγοντες που επηρεάζουν αυτήν και η αξιολόγηση των εκτιμούμενων παραμέτρων, με ιδιαίτερη έμφαση στην κινητικότητα των σπερματοζωαρίων. Ο αναλυτής CASA αποτελεί σημαντικό εφόδιο για τους ασχολούμενους με τη διαχείριση υγείας των παραγωγικών ζώων, ωστόσο απαιτείται τήρηση των κανόνων για ορθή εκτίμηση των δειγμάτων και για αξιοπιστία και δυνατότητα σύγκρισης των αποτελεσμάτων.Objective of this review is to present the use of ‘Computer Assisted Semen Analysis’ technique application in farm animal health management, in particular the steps for accurate semen evaluation and the impact of the method in predicting male animal fertility under field conditions. Requirements for proper use of the equipment, factors affecting the evaluation process and the role of the estimated parametres for fertility under field conditions are described. Special reference is made in sperm motility evaluation. It is concluded that the method is an effective and efficient tool for semen evaluation, provided good practices are strictly applied and adhered to, by means of which valid results may be obtained
The changing global distribution and prevalence of canine transmissible venereal tumour.
BACKGROUND: The canine transmissible venereal tumour (CTVT) is a contagious cancer that is naturally transmitted between dogs by the allogeneic transfer of living cancer cells during coitus. CTVT first arose several thousand years ago and has been reported in dog populations worldwide; however, its precise distribution patterns and prevalence remain unclear. RESULTS: We analysed historical literature and obtained CTVT prevalence information from 645 veterinarians and animal health workers in 109 countries in order to estimate CTVT's former and current global distribution and prevalence. This analysis confirmed that CTVT is endemic in at least 90 countries worldwide across all inhabited continents. CTVT is estimated to be present at a prevalence of one percent or more in dogs in at least 13 countries in South and Central America as well as in at least 11 countries in Africa and 8 countries in Asia. In the United States and Australia, CTVT was reported to be endemic only in remote indigenous communities. Comparison of current and historical reports of CTVT indicated that its prevalence has declined in Northern Europe, possibly due to changes in dog control laws during the nineteenth and twentieth centuries. Analysis of factors influencing CTVT prevalence showed that presence of free-roaming dogs was associated with increased CTVT prevalence, while dog spaying and neutering were associated with reduced CTVT prevalence. Our analysis indicated no gender bias for CTVT and we found no evidence that animals with CTVT frequently harbour concurrent infectious diseases. Vincristine was widely reported to be the most effective therapy for CTVT. CONCLUSIONS: Our results provide a survey of the current global distribution of CTVT, confirming that CTVT is endemic in at least 90 countries worldwide. Additionally, our analysis highlights factors that continue to modify CTVT's prevalence around the world and implicates free-roaming dogs as a reservoir for the disease. Our analysis also documents the disappearance of the disease from the United Kingdom during the twentieth century, which appears to have been an unintentional result of the introduction of dog control policies.This is the author's accepted manuscript. The final version of this article has been published by BioMed Central: http://www.biomedcentral.com/1746-6148/10/168