This chapter addresses the nutritional, husbandry and disease processes which affect ewes and their foetuses in the time from early pregnancy to parturition and through early lactation. Nutrition of the ewe through pregnancy has a major effect on her health, her ability to deliver robust and healthy lambs and her ability to bond with, protect and nourish her lambs in the neonatal period. It also has major effects on the survival rate of the lambs in the neonatal period. Some of the most common clinical diseases which affect ewes during pregnancy are pregnancy toxaemia and hypocalcaemia, and these conditions are most effectively prevented by flock management strategies. There are numerous infectious agents which can cause abortion in ewes. Many of these agents can also cause stillbirths and the birth of lambs of low birthweight and poor viability. The normal behaviours of ewes and lambs at parturition are described. Factors which interfere with the development of a strong bond between ewes and lambs, and factors which reduce the intake of sufficient nutrients by lambs soon after birth, have a major effect on the probability of lamb survival in the first few days of life. Perinatal mortality in lambs is one of the most important causes of economic loss to the Australian sheep industry. Veterinary investigations of perinatal mortality can identify the steps that need to be taken to reduce perinatal mortality on sheep farms. Adequate nutrition of the lactating ewe is essential to achieve satisfactory health and growth in their lambs. The most important disease condition of the lactating ewe is mastitis.

Context In Australia, it is a common practice to dock sheep tails, to reduce breech soiling and flystrike. According to research, for docking to provide the optimal benefit, tails should be left at a length that covers the vulva in ewes and to an equivalent length in males. Docking tails shorter than recommended increases the risk of perineal cancers, arthritis and prolapse. Research indicates that some producers dock tails shorter than recommended, up to 57% in surveys and up to 86% in on-farm data. Aims This study aimed to ascertain the current tail docking length, practices, knowledge and attitudes of Australian sheep producers. Methods A national survey was conducted using online, hardcopy and computer-assisted telephone interview (CATI) modes of delivery (n = 547). Key results Fifty-seven percent (205/360) of online and hardcopy survey participants chose short tail images to represent their practice, where the vulva was exposed. Although 88% (135/154) of CATI participants described their sheep tail lengths to be covering the vulva, participants equated the length to leaving two tail joints (40%, 54/134) and/or 50 mm (29%, 39/134), both of which have been previously found to be too short to cover the vulva. There was a high awareness of the recommended length (75.7%, 408/539) and 60% (234/390) of participants described it accurately. Significant associations were identified between choosing the short tail image and (1) describing the recommended length to be shorter than it is (P < 0.01), (2) being a producer in South Australia (P < 0.05), and (3) practicing mulesing (P < 0.01). Tail docking is important for producers to reduce flystrike, but docking at their chosen length held more importance than following the recommendation. Participants tended to agree that shearers preferred short tails. Docking tails with a hot knife or rubber rings were the most common methods used. Conclusions These results indicated that short tail docking remains a sheep-welfare issue for Australian sheep, and that a knowledge–practice gap exists for some producers. Implications Future research in the space of tail length could address the identified knowledge–practice gap, attitudes, and individual barriers to benefit sheep welfare and the industry.

Over the past 20 years, a lower percentage of veterinary and animal science students entering Australian and New Zealand schools have a background or ongoing contact with livestock production systems. The increasing use of digital technologies over the same time provides a practical option to introduce students to the seasonal operations on livestock farms. This article describes the development of the 4D Virtual Farm, established to showcase 11 representative livestock farms across Australasia allowing students to virtually travel through seasons and place over each farming enterprise. Students can virtually visit different beef cattle, prime lamb, wool-sheep and dairy cattle farms, and a piggery. Any electronic device connected to the web including mobile phones, tablets, computers, and virtual reality headsets can be used to view the enterprises. For educators, the virtual farm can be used for a range of teaching and learning scenarios, such as demonstration of a particular production system via weblink for lectures or embedding within learning management systems. It also allows students to start at a particular point in time and space and guide themselves to other areas for self-learning or for a range of assessment tasks. This site provides an example that could be used in other teaching areas including abattoirs, exotic diseases, surgery, communication, and many other veterinary examples.

Docking sheep tails is a long-standing practice that, when done at the recommended length, reduces the risk of flystrike. The recommended length is to cover the vulva of ewes and to a similar length in males. This length is often equated to three coccygeal joints left intact, and there are many other ways the recommended length is described by researchers, industry, and government. This study compared the observer consistency and retest consistency using three different tail length measurement methods: vulva cover assessment, length (mm), and joint palpation. The tails of 51 yearling and 48 weaner Merino ewes were assessed by two observers. Length and vulva cover assessment methods provided the most reliable results, and joint palpation was the least reliable method of tail measurement. In the sample, tails that covered the vulva of yearlings and weaners measured 57.6 mm (n = 14) and 63.7 mm (n = 30) on average, respectively, and contained two coccygeal joints (more than two coccygeal vertebrae). Tails that did not cover the vulva of yearlings and weaners measured 41.3 mm (n = 36) and 52.8 mm (n = 17) on average, respectively, and had less than two coccygeal joints. The two most reliable methods enable valid comparison to the best practice recommendations.

This article describes a blended synchronous learning (BSL) case study program in veterinary science, including the physical space for the program. The student cohort in this program was diverse with students from more than ten countries and four continents. Traditionally, the program was only provided in a face-to-face (F2F) format, before moving to completely on-line during the early COVID pandemic and then to the current BSL format with most learners located in the F2F location. The 145 students in the program were broken into two classes with groups of up to eight students working together in each class with some students online and some F2F in each group. Tools used to aid the integration of the blended class included Canvas learning management system (LMS), Zoom, Padlet, Peerwise, 4D Virtual Farm and Poll Everywhere. Students were instructed on the use of the technologies on the LMS platform and in the initial case study as part of the cohort getting to know each other. The use of the BSL environment allowed all students to participate in each case study irrespective of their physical location and allowed production of review material. The technology allowed students to interact within and between groups well, albeit there were challenges with audio in small group Zoom breakouts, depending on the device being used.

All veterinary schools in Australasia require students in the first half of their course to complete work integrated learning (WIL) during vacation time on a range of animal enterprises. This allows students to gain an understanding of how the enterprises function on a day to day basis and compare to the theoretical training that students receive on-campus. The time on-property required is equivalent to 60 days of work with a requirement to visit several enterprises (AVBC, 2016). COVID-19 required immediate cessation of all on-property placements. Given the limited number of holiday weeks available for WIL we developed an on-line experiential program to support student learning. The backbone of the online WIL experience relied on previously developed or developing virtual reality (VR) farm resources; the 4DVirtual Farm and DookieVR (Barber etal, 2016). These resources allow students to visit properties via multiple 360 images through time on a property, allowing virtual travel through time and place to see what happens on an enterprise throughout a year. They also integrate environmental variables and both 360 and standard video to provide access to further information. They are viewable using mobile phones, laptop and desktop systems as well as VR viewers. The basic VR resource allows students to take their own tour around the property however the week of experiential learning was planned to reinforce the students’ ability to see what happens on the individual property throughout the year. This compares to an individual property visit where a student gains more “hands-on” insight for a much more limited timespan of the year, usually 1-2 weeks. The week of synchronous, experiential learning used Zoom as the primary tool to allow communication between staff and students with content managed on the learning management system, Canvas. The standard format for each day involved an initial entire class group session, mostly in didactic information transfer from staff to students and then a mixture of small group, full class or individual tasks. Assessment of content understanding was evaluated on a regular basis using multiple choice questions or word responses using PollEverywhere. The large class group of 100-250 students broke into small virtual rooms of 6 to 8 students. Each day this small student group had a task to complete and submit via Feedback Fruits, which then allocated individual students to provide written feedback on the group report by the next day. Time was allocated for students to review these reports both individually and then to discuss the multiple reports that group members were assessing and submit feedback. In addition, each small group reported on a relevant name to the veterinary industry, either from current or historical times. A short video detailing the link of this name to the veterinary industry was posted to Flipgrid for both staff and other students to review. Student understanding of the week was measured at the commencement and completion of the week using an online multiple choice quiz as well as receiving student feedback by an online survey. This presentation will cover the background, development and design of the week and associated material. References AVBC (2016), Standard 9.3 Extra Mural Studies (EMS or Workplace Learning), page 32, Australasian Veterinary Boards Council, https://avbc.asn.au/wp-content/uploads/documents/public/AVBCStandardsAug2016.pdf Barber S, Hallein E, Shallcross D, Weston J, Jacobson C, Bramley E, Celi P, McGowan M (2016), Final report: Development of 4D farms to improve student learning and safety, Office of Learning and Teaching https://ltr.edu.au/resources/ID12_2365_Barber_Report_2016.pdf

BACKGROUND:Producing graduates for a breadth of sectors is a priority for veterinary science programs. Undergraduate career intentions represent de-facto 'outcome' measures of admissions policy and curricula design, as intentions are strong predictors of eventual behaviour. Informed by Ajzen's Theory of Planned Behaviour, this study aimed to identify if contextually relevant attitudes and self-ratings affect student intentions for veterinary career sectors.RESULTS:Survey responses from 844 students enrolled in five Australian veterinary programs in 2014 were analysed. Intention was measured for biomedical research/academia, industry, laboratory animal medicine, public health/government/diagnostic laboratory services, mixed practice, intensive animal production, companion animal practice, not work in the veterinary profession, and business/entrepreneurship. Hierarchical multiple linear regression analysis enabled comparison of explanation of variance in intent by demographics, animal handling experience, species preference, and attitudes to aspects of veterinary work. Career sector intentions were highest for mixed or companion animal clinical practice, then business/entrepreneurship, then non-clinical sectors. Overall, intent was explained to a greater extent by species preferences than by animal experience, attitudes to aspects of veterinary work and demographics (with the exception of mixed practice intent) with gender having no significant effect. Several variables exerted negative effects on career intent for less popular career sectors.CONCLUSION:Ajzen's Theory of Planned Behaviour (TPB) provides a framework to increase understanding of and predict career sector intentions. Incorporation of attitude and self-efficacy measures in our study revealed preference for species types contributes greatly to career sector intentions for veterinary students, particularly for the more popular practice based sectors. Importantly, specific species preferences and other attitudes can have a negative effect on intent for non-aligned veterinary sectors. Further research is required to identify additional attitudes and/or beliefs to better explain variance in intent for less popular career sectors. Veterinary admissions processes may benefit from utilising the TPB framework. Identified effects revealed by this study may stimulate innovation in marketing, recruitment, admissions and curricular design, such as timing and role modelling, to utilise positive effects and mitigate against negative effects identified for sectors requiring greater representation of career intent in the student body.

Lymphatic cannulation models are useful tools for studying the immunobiology of the lymphatic system and the immunopathology of specific tissues in diseases. Sheep cannulations have been used extensively, as models for human physiology, fetal and neonatal development, human diseases, and for studies of ruminant pathobiology. The development of new and improved cannulation techniques in recent years has meant that difficult to access sites, such as mucosal associated tissues, are now more readily available to researchers. This review highlights the new approaches to cannulation and how these, in combination with advanced omics technologies, will direct future research using the sheep model.

This study examined variation in the welfare of extensively managed ewes and potential welfare risks. A total of 100 Merino ewes (aged 2–4 years) were individually identified and examined at three key stages: pregnancy, lactation and weaning. Eight animal-based welfare measures were used to assess welfare: flight distance, body condition score (BCS), fleece condition, skin lesions, tail length, dag score, lameness and mastitis. Data were analysed by ANOVA and McNemar’s statistics. Overall, the average BCS of the group was in agreement with industry recommendations. However, a number of animals were classified with inadequate condition (either too thin or too fat) across the three observation periods. The presence of heavy dags was greatest at mid-lactation (87%, P < 0.0001), lameness was greatest at weaning (14%, P = 0.01), clinical mastitis was 1% annually, and five ewes were lost from the study. Ewes had better health at mid-pregnancy compared to mid-lactation and weaning. The main welfare issues identified were under and over feeding, ewe mortality, lameness, ecto-parasites (flystrike) and mastitis, all of which have the potential to be reduced with improved management practices. Future welfare assessment programs must consider that significant variation in on-farm welfare will occur in extensively managed systems and this needs to be accounted for when evaluating farms.

OBJECTIVE:Regarded as one of the most expensive production diseases of dairy sheep and goats, contagious agalactia (CA) is caused by any of four agents: Mycoplasma agalactiae, M. mycoides subspecies capri (Mmc), M. capricolum subspecies capricolum (Mcc) and M. putrefaciens. Although CA is worldwide in distribution, it has not been reported in Australia, even though studies between the 1950s and 1980s isolated each agent from sheep or goats without any clinical signs associated with it. The aim of this study was to examine sheep and goats in Victoria, Australia, for the presence of CA-associated mycoplasmas and to investigate the evolutionary relationships of these isolates by comparing their genetic differences with their counterparts from other parts of the world.METHODS:A 3-year epidemiological survey of small ruminant populations in Victoria, Australia, was conducted for the presence of CA-associated mycoplasmas and the isolates obtained were genotyped by multilocus sequence typing (MLST).RESULTS:Mmc was the only CA-associated agent isolated from the 1358 samples analysed in the study, but was not associated with CA on the property where it was found. MLST analyses of Mmc strains revealed a distinct clustering of Australian isolates into a novel clade, with the closest relatives being strains from Europe. The distinct clustering is consistent with the absence of clinical disease in Australia.CONCLUSION:The isolation of Mmc indicates that this subspecies persists in Australian small ruminant populations. However, full genome sequencing and in vitro animal experimentation are needed to unequivocally demonstrate the avirulence of Australian strains.

The aetiology and epidemiology of outbreaks of clinical mastitis in sheep under extensive pastoral conditions are incompletely understood. The objective of this study was to conduct a detailed investigation of a clinical mastitis outbreak that affected more than 10% of 230 at-risk ewes on a sheep and grain producing property in south east Australia during drought conditions in 2009. Milk samples were collected aseptically from all affected ewes and plated on sheep blood agar for bacterial identification. M. haemolytica was isolated from 80% of the samples that yielded cultivable microorganisms and thus was the main microorganism responsible for the outbreak. Analysis of the restriction endonuclease cleavage patterns of the isolates using pulsed field gel electrophoresis revealed some evidence of clonality, suggesting the possibility of horizontal transmission, but there was also considerable diversity between the clusters of closely related isolates. Multilocus sequence typing of the M. haemolytica isolates revealed most of the isolates belonged to ST1 with no association between the PFGE and MLST fingerprints of the isolates. Resistance to neomycin, streptomycin and sulphafurazole was detected in some of the isolates, but they were all susceptible to penicillin, ampicillin, ceftiofur, amoxycillin/clavulanic acid, ciprofloxacin, tetracycline, erythromycin and trimethoprim. This is the first published record of a comparison of the strains of M. haemolytica involved in a clinical mastitis outbreak in sheep and demonstrates the importance of this pathogen in sheep production systems, particularly during adverse climatic conditions and increased stocking rate.

Background: Two mammary lymphatic cannulation models in sheep have been described with minimal use in the past 50 years. The purpose of this study was to investigate a new surgical technique to allow long term monitoring of mammary lymph flow and composition from the mammary glands, with rapid ewe recovery and minimal complications post-surgery.Results: We developed a modified methodology for cannulating the efferent mammary lymphatic from the mammary lymph node with minimum tissue damage. Compared to the previous models, our method required only a small incision on the aponeurosis of the external abdominal oblique muscles and thus reduced the difficulties in suturing the aponeurosis. It allowed for lymph collection and assessment for at least one week post-surgery with concurrent milk collection.Conclusion: This method allows for good ewe recovery post-surgery and in vivo sampling of efferent mammary lymph from the mammary lymph nodes in real-time and comparison with milk parameters.

Lamb suckling has been suggested to be an important way of infecting a ewe's udder with different bacteria, including Mannheimia haemolytica. To test the potential role of lambs in transferring Mannheimia species to the ewe's udder, the restriction endonuclease cleavage patterns of isolates obtained from nasopharyngeal swabs were compared with those obtained from cases of mastitis. Sterile cotton swabs were used to collect nasopharyngeal samples from 50 ewes and 36 lambs from three flocks. M. haemolytica and Mannheimia glucosida as well as haemolytic Mannheimia ruminalis-like organisms were detected in the upper respiratory tract of lambs and ewes. Comparison of the restriction endonuclease cleavage patterns of the isolates suggested that the M. haemolytica isolates obtained from different milk samples from ewes with mastitis were more clonal than those obtained from the nasal swabs. However, some nasal isolates within both Mannheimia species had restriction endonuclease cleavage patterns identical to those obtained from milk samples from ewes with mastitis, indicating that lambs may have a role in transferring these organisms to the udder. More clonality was observed between the M. glucosida isolates than between M. haemolytica isolates.

ABSTRACT Mannheimia spp. are veterinary pathogens that can cause mastitis and pneumonia in domestic cattle and sheep. While Mannheimia glucosida can be found as normal flora in oral and respiratory mucosa in sheep, there have been no reported cases of human infection with this organism.

The contribution of Mycoplasma arginini to mycoplasmosis in small ruminants remains unclear because it is recovered from both healthy and diseased animals. In order to gain a better understanding of any relationships between isolates from different sites and different geographical locations, we developed a method for genotyping M. arginini using multilocus sequence typing (MLST). A MLST scheme based on five housekeeping genes was used to characterize M. arginini isolates from flocks of sheep and goats. A high level of genetic variability was detected between strains and within herds.

Species within the genus Mannheimia are among the most important causes of ovine mastitis. Isolates of these species can express leukotoxin A (LktA), a primary virulence factor of these bacteria. To examine the significance of variation in the LktA, the sequences of the lktA genes in a panel of isolates from cases of ovine mastitis were compared. The cross-neutralising capacities of rat antisera raised against LktA of one Mannheimia glucosida, one haemolytic Mannheimia ruminalis, and two Mannheimia haemolytica isolates were also examined to assess the effect that variation in the lktA gene can have on protective immunity against leukotoxins with differing sequences. The lktA nucleotide distance between the M. haemolytica isolates was greater than between the M. glucosida isolates, with the M. haemolytica isolates divisible into two groups based on their lktA sequences. Comparison of the topology of phylogenetic trees of 16S rDNA and lktA sequences revealed differences in the relationships between some isolates, suggesting horizontal gene transfer. Cross neutralisation data obtained with monospecific anti-LktA rat sera were used to derive antigenic similarity coefficients for LktA from the four Mannheimia species isolates. Similarity coefficients indicated that LktA of the two M. haemolytica isolates were least similar, while LktA from M. glucosida was most similar to those for one of the M. haemolytica isolates and the haemolytic M. ruminalis isolate. The results suggested that vaccination with the M. glucosida leukotoxin would generate the greatest cross-protection against ovine mastitis caused by Mannheimia species with these alleles.

While Mannheimia haemolytica and Mannheimia glucosida have been recognized as causes of intramammary infection in sheep, there has been no investigation of the epidemiology of the strains involved. Pulsed field gel electrophoresis was used to study the molecular epidemiology of isolates of these 2 species associated with ovine mastitis. Ten distinct strains were recognized among 12 M. haemolytica isolates, and 7 distinct strains among 13 M. glucosida isolates. The results demonstrate a high diversity of isolates with the ability to cause ovine mastitis. However, the presence of some identical isolates may suggest the possibility of horizontal transmission of these species in some flocks, possibly through lamb sucking, and/or differences in the capacity of some isolates to cause mastitis in sheep.

Mannheimia haemolytica is known to be an important cause of intramammary infection in sheep. It usually causes severe clinical mastitis, followed by toxaemia and gangrenous necrosis of the udder. However there are limited data available on the epidemiology and pathogenesis of mastitis associated with Mannheimia species. These organisms can be more significant as a cause of mastitis than Staphylococcus aureus in some flocks. Some data suggest the possibility of horizontal transmission of Mannheimia species between ewes via lamb sucking. There is no vaccine available for prevention, and the sudden onset of mastitis and its peracute nature renders most treatments unsuccessful. This review examines the significance of the species within this genus in sheep mastitis.

ABSTRACT Mannheimia glucosida , M. haemolytica , and M. ruminalis were isolated from cases of acute mastitis in ewes. M. glucosida was found to be a common cause of clinical mastitis in sheep. Selected phenotypic tests in addition to genotyping were needed to definitively identify Mannheimia species causing ovine mastitis.