Pegbovigrastim injection (IMR) represents a new approach in overcoming mastitis. The objective of this study was to evaluate production parameters, overall health, time to first detected heat, and behavior of cows treated with IMR or a saline control. Study cows (n = 270) were blocked by parity group (multiparous or primiparous) and randomly assigned to control (CON, n = 144) or treatment (IMR, n = 126). Milk yield, fat, protein, lactose, solids nonfat percent, somatic cell count, and body condition, hygiene, and lameness were evaluated weekly. Animals were evaluated for metritis twice weekly via evaluation of rectal temperature, per rectum palpation, and uterine discharge until 30 days in milk. Farm staff recorded occurrence of other diseases. Neck tag and a leg tag, each with activity monitoring sensors, measured behavior and time to first detected estrus. The occurrence of clinical mastitis did not differ between treatments. Treated cows were 2.46 times more likely to develop metritis compared to control cows. Cows given IMR had increased odds of developing metritis, without altering mastitis occurrence, production parameters, behavior, and time to first heat in lactating dairy cows.

Precision dairy monitoring technologies can be used to monitor changes in physiology and behavior associated with transition period postpartum diseases and heat stress. Research Objective One was to evaluate how traditional visual examination, body condition, and locomotion with and without blood, milk, and urine variables and precision dairy monitoring technologies determine variable association with hyperketonemia, metritis, mastitis, hypocalcemia and retained placenta,. This was accomplished by monitoring cows 2 weeks before calving to 3 weeks after calving for any postpartum diseases using daily visual examination and automatically detected variables including activity, milk yield, milk components, lying behavior, feeding behavior, rumination time, and reticulorumen temperature. Deviations in reticulorumen temperature, milk production, eating time, lying time, and activity were detected by precision dairy monitoring technologies among cows with postpartum diseases. Research Objective Two was to determine the association between automatically detected variables and heat stress. This objective was accomplished by monitoring cows under natural ventilation, fans, and fans plus sprinklers for variations under each condition. Changes in physiology and behavior as detected by precision dairy monitoring technologies was associated with postpartum diseases and heat stress. Using precision dairy monitoring technologies and visual examinations may aid producers in identifying postpartum disease and heat stress.

This dissertation describes the epidemiological investigation and management of the first outbreak of Contagious Equine Metritis (CEM) reported in South Africa. In addition, the subsequent implementation of a nationwide quantitative polymerase chain reaction (qPCR)- based stallion screening programme and traceback of exposed animals to define the spread of CEM in South Africa is described. The first South African outbreak of CEM caused by the bacterium, Taylorella equigenitalis was reported on the 9th May 2011 to the World Health Organisation for Animal Health (OIE). The outbreak was recognized subsequent to the importation of a young Warmblood stallion from Germany. The outbreak initially appeared confined to a single index property (focus property), an equine breeding facility in Midrand, Gauteng, South Africa with a single confirmed case of transmission involving the index stallion and a Thoroughbred mare. The initial response was rapidly instituted following the suspicion of T. equigenitalis on the index property. This included an inspection of the index property and its records. A riskclassification of in-contact animals allocated them to “high,” “moderate” or “low”-risk categories. The classification was dependent on the temporal relationship of their presence on the index property relative to the period of residence of the index cases. After T. equigenitalis infection was confirmed from both index cases, the breeding facility was placed under state– administered quarantine and all exposed mares and the index cases were transferred to a quarantine facility. The animals were re-tested by genital swabbing for bacterial culture following a standard protocol according to internationally-accepted practice (OIE Terrestrial Manual on Contagious Equine Metritis). Additional duplicate swabs were obtained for real time qPCR. None of the mares were shown to be positive on either bacterial culture or qPCR. All animals were however treated according to an accepted protocol for T. equigenitalis infection (Luddy and Kutzler, 2010, UK Horseracing Betting Levy Board (HBLB) Code of Practice, 2011). All stallions that had been present on the index property and undergone semen collection on the same day as the index stallion were classified as “moderate risk” and were similarlytested. This identified two additional T. equigenitalis-positive stallions, which were confirmed on bacterial culture (World Organization for Health (OIE) Manual of Diagnostic Tests and Vaccines for Terrestrial Animals (Chapter 2.5.1, Contagious Equine Metritis version adopted 20/10/2011) and which were subsequently quarantined and successfully treated. Following recognition of this outbreak, the Department of Agriculture, Forestry and Fisheries (DAFF) in consultation with the Equine Research Centre (ERC) of the Faculty of Veterinary Science at the University of Pretoria promulgated a nationwide qPCR-based screening programme that aimed to establish the prevalence and distribution of T. equigenitalis in South Africa. This required certification of all South African stallions used for breeding either by natural cover or assisted reproductive techniques. The compliance for certification was based on submission of two sets of genital swabs that both tested negative for T. equigenitalis on qPCR-testing. The process was coordinated by a web-based platform (http://wto the prescribed World Organisation for Health (OIE) method (Terrestrial Manual on Contagious Equine Metritis). All stallions apart from one could be linked to the index property. As of 31st October 2013, two additional T. equigenitalis-positive females have been identified, following a traceback of all identified potentially-exposed mares and their offspring that was instituted in September 2012. An “exposed mare” was defined as a mare that had been bred, either by natural breeding or assisted breeding techniques to the index stallion or any other T. equigenitalis-positive stallion. These mares were distributed across five provinces of South Africa at the time the traceback was initiated. During the nationwide traceback, a subpopulation focus was identified when 24 of the 33 resident stallions at the South African Lipizzaner Centre, Midrand, Gauteng tested positive for T. equigenitalis. Six of these stallions had visited the index property for semen collection over the course of several years prior to the arrival of the index stallion. This suggested the possible albeit undetected presence of T. equigenitalis on these premises prior to the arrival of the first reported index case. We strongly suspected that there may have been undetected CEM incursions into South Africa in the past. The index case in this outbreak may either have introduced a new infection or was infected by a pre-existing source of infection subsequent to his arrival. It is hoped that future strain-typing of the isolates from the positive cases identified during this intervention will further clarify this scenario. The use of qPCR-based screening proved to be a highly specific and sensitive method for detecting T. equigenitalis and helped to define the distribution and prevalence of T. equigenitalis in breeding stallions and exposed mares in South Africa. In addition, this method had significant practical advantages with respect to the associated costs, turn-around times and in-the-field application when compared with bacterial culture. The institution of a web-based platform from which the national screening programme was launched and coordinated proved to be indispensable in managing stakeholder access and information availability. To date, 31st October 2013, a total of 39 horses (36 males and 3 females) have been identified as T. equigenitalis-positive and have all subsequently been successfully treated. © Universityww.cemsa.co.za) As of 31st October 2013, an additional 33 carrier stallions have been identified by this screening programme. Of these stallions, 23 have been confirmed on bacteriology according to the prescribed World Organisation for Health (OIE) method (Terrestrial Manual on Contagious Equine Metritis). All stallions apart from one could be linked to the index property. As of 31st October 2013, two additional T. equigenitalis-positive females have been identified, following a traceback of all identified potentially-exposed mares and their offspring that was instituted in September 2012. An “exposed mare” was defined as a mare that had been bred, either by natural breeding or assisted breeding techniques to the index stallion or any other T. equigenitalis-positive stallion. These mares were distributed across five provinces of South Africa at the time the traceback was initiated. During the nationwide traceback, a subpopulation focus was identified when 24 of the 33 resident stallions at the South African Lipizzaner Centre, Midrand, Gauteng tested positive for T. equigenitalis. Six of these stallions had visited the index property for semen collection over the course of several years prior to the arrival of the index stallion. This suggested the possible albeit undetected presence of T. equigenitalis on these premises prior to the arrival of the first reported index case. We strongly suspected that there may have been undetected CEM incursions into South Africa in the past. The index case in this outbreak may either have introduced a new infection or was infected by a pre-existing source of infection subsequent to his arrival. It is hoped that future strain-typing of the isolates from the positive cases identified during this intervention will further clarify this scenario. The use of qPCR-based screening proved to be a highly specific and sensitive method for detecting T. equigenitalis and helped to define the distribution and prevalence of T. equigenitalis in breeding stallions and exposed mares in South Africa. In addition, this method had significant practical advantages with respect to the associated costs, turn-around times and in-the-field application when compared with bacterial culture. The institution of a web-based platform from which the national screening programme was launched and coordinated proved to be indispensable in managing stakeholder access and information availability. To date, 31st October 2013, a total of 39 horses (36 males and 3 females) have been identified as T. equigenitalis-positive and have all subsequently been successfully treated. / Dissertation (MMedVet)--University of Pretoria, 2013. / gm2014 / Production Animal Studies / unrestricted

No description available.

The metritis complex (MC), characterizing post-partum uterine diseases in dairy cattle has negative implications on animal welfare, production efficiency, and the economic stability of the dairy industry. The studies in this thesis aimed to investigate the genetic architecture of the metritis complex and identify genomic regions and metabolites associated with the development of MC. Thereby enhancing our understanding of the biological pathways and molecular mechanisms involved in the pathophysiology of MC during the transition period in Jersey and Holstein dairy cattle. Chapter 2 sheds light on the previous work done on MC. The goals of this review were to (1) provide an updated epidemiological profile of uterine ailments, (2) integrate results from genomics, transcriptomics, metabolomics, and proteomics (OMICs) studies to reveal insights on the identified biological pathways modulated during the transitional period and the onset of metritis, and (3) discuss the commonly detected molecular mechanisms in OMICs studies. Chapter 3 utilized genomic profiles to identify genetic variants, genes, and biological pathways that modulate MC development. A genome-wide association study (GWAS) was performed using a single locus mixed linear model on 1,967 Holstein and Jersey cow genotypes (624,460 SNPs), and MC records from three dairy herds. Following this, in-silico functional and gene network analyses were performed to detect biological mechanisms and pathways linked to the development of endometritis, metritis, and pyometra, diseases defined under the metritis complex development. Potential genes were significantly (P ≤ 0.0001) associated with MC and located on chromosomes 12, 10, and 21. These genes are involved in potential metabolic pathways which are directly associated with the mode of transmission for well-known pathogens in the metritis complex. Chapter 4 followed the GWAS with a high-throughput liquid chromatography-mass spectrometry (LC-MS) metabolomic study. The goals of this study were to 1) to identify metabolites associated with the development of MC in multi-parous Jersey and Holstein cows, 2) to detect the molecular pathways linked to the identified metabolites for MC, and 3) and to identify potential metabolomic biomarkers for early detection of uterine disease development in dairy cattle following parturition. A case-control design was employed on transitioning dairy cattle (n=28), at three time points (week 1, 2, and 3 post-calving). The study identified 48 significant (at false discovery rate adjusted P≤0.05) metabolic deviations for MC during the second week post-partum using single point t-test model. Using repeated measurement, 50 metabolites were identified as significant across all three time points. The results from the studies done revealed mechanisms contributing to the development of uterine disease in Jersey and Holstein breeds. These results should be validated and may be used as genomic selection or management tool to decrease the incidence of metritis complex in dairy cattle.

Les objectifs de cette étude ont été de : (1) déterminer s’il existe une association entre la présence intra-utérine d'Escherichia coli dans la 1 ère semaine postpartum et le développement de la métrite postpartum, (2) déterminer s’il y a une association entre les gènes de virulence d'E. coli et la métrite postpartum, et (3) d'évaluer si les analyses bactériologiques (bactéries et gènes de virulence d'E. coli) pourraient prédire la métrite postpartum chez la vache laitière. Des écouvillons utérins ont été prélevés dans la première semaine postpartum sur 486 vaches de race Holstein et soumis au laboratoire pour détection de E. coli. Les gènes de virulence d'E. coli ont été identifiés par la technique d'hybridation des sondes radioactives. Un total de 252 vaches (52%) ont été positives à E. coli et 67 vaches positives à la métrite postpartum (13,7%). Les vaches positives à E. coli intra-utérin dès la première semaine postpartum avaient un risque 2,6 fois plus élevé de développer la métrite postpartum que les vaches sans E. coli. La plupart des E. coli possédaient un ou plusieurs gènes des E. coli d'origine extra-intestinale (ExPEC) dont fimH (89%), HlyE (87%) et iss (70%). Parmi les autres gènes ExPEC, on a retrouvé sitA (23%), fepC (20%) hra1 (20%) malX (14%) tsh (11%) et bien d'autres. Les gènes de virulence kpsMTII et hra1 ont été associés à la métrite postpartum avec un rapport de cote de 4,3 chacun. La présence d'E. coli dans l'utérus avait une valeur prédictive positive de 18% tandis que la présence des gènes kpsMTII et hra1 avait une valeur prédictive positive de 36% et 31% respectivement. La détection de certains gènes de virulence d'E. coli dans les prélèvements utérins pourrait renseigner sur le risque de développement de la métrite postpartum chez la vache laitière. Les études ultérieures pourraient tester encore plus de gènes et viser à développer des tests de dépistage simple, facilement et rapidement applicable à la ferme. / The objectives of this study were to (1) determine whether there is an association between the presence of intra-uterine Escherichia coli in the first week postpartum and the occurrence of postpartum metritis in the subsequent weeks, (2) determine whether there is an association between E. coli virulence genes and postpartum metritis, and (3) to assess whether the presence of these E. coli virulence genes could predict the occurrence of postpartum metritis in dairy cows. Uterine swabs were collected in the first week postpartum from 486 Holstein cows and submitted to the laboratory for detection of E. coli. Virulence genes of E. coli were identified using the radioactive probe hybridization method. A total of 252 cows (52%) were positive for intra-uterine E. coli and 67 cows (13.7%) were positive for postpartum metritis. Cows positive for intra-uterine E. coli in the first week postpartum had 2.6 times the odds of developing postpartum metritis compared to negative cows. Most intra-uterine E. coli possessed one or more ExPEC genes, among which FimH (89%), hlyE (87%), and iss (70%). Other ExPEC genes such as sitA (23%), fePC (20%) hra1 (20%) malX (14%) tsh (11%) and others were found with low prevalence. The presence of the virulence genes kpsMTII and hra1 was associated with 4.3 times each the odds of developing postpartum metritis compared to negative cows. The presence of E. coli in the uterus had a positive predictive value of 18%, while the presence of the genes kpsMTII and hra1 had a positive predictive value of 36% and 31% respectively. The detection of certain virulence genes of E. coli in uterine swabs could inform about the risk of developing postpartum metritis in dairy cattle. Further studies could test more virulence genes and aim at developing molecular tests that would be simple, quickly and easily applicable on farm.

A multiple trait, random regression, test day (TD) model was used to determine the heritability and genetic correlations of milk, fat, protein, and SCS with metritis, cystic ovary disease, mastitis, lameness, ketosis, milk fever, and displaced abomasum for four periods in lactations 1, 2, and 3-5 using two disease definitions. Definition 1 assumed that the first disease occurrence affects all TD thereafter equally and definition 2 assumed that disease affects only the next TD. Results were similar between definitions. The models were modified to allow the estimation of differences in disease occurrence by level of production, and to estimate production differences between diseased and non-diseased cows. Few significant associations were found between production levels and disease occurrence, the largest was between MAST and SCS. Diseased animals had lower levels of production than healthy animals for all diseases except COD. Animals with MAST had increased SCS. / Natural Sciences and Engineering Research Council (NSERC). Dairy Cattle Genetics Research and Development (DairyGen) Council.