AVA Conference Adelaide 2016

I worked for Stanbroke Pastoral Company from 1997 until 2003, when it was sold. During that time the herd expanded from 300,000 head to 530,000 head and my job title changed from VETERINARIAN to GENERAL MANAGER, LIVESTOCK HEALTH AND PRODUCTION, RESEARCH and RANGELANDS. The herd was predominantly Bos indicus x and the properties were mostly in northern Australia. By contrast, when working for Bryansk Meat Company in the south west of Russia, I started as ASSOCIATE VETERINARIAN and graduated to HEAD VETERINARIAN in the 6 months I was there, from September 2014 to May 2015. During that short period the herd expanded from 200,000 to 300,000 Angus cattle and from 28 to 33 farms. My presentation will cover productivity, disease, animal welfare and staff communication challenges for an Australian female veterinarian working in the dry tropics of the northern Australian cattle industry with 600 predominately male co-workers and in the temperate environment of Russia with 6000 predominantly male co-workers that did not speak English

Assurance in Australia’s animal health status underpins the ‘clean, green’ image of Australia’s animal industries and our competitive advantage in international markets. It also supports domestic consumer confidence in Australian livestock products. This presentation will outline the importance of animal health surveillance in supporting trade, mitigating the risk of serious disease outbreaks and (in the case of zoonotic diseases) safeguarding the health of people. It will explain the imperatives for surveillance in the face of a growing risk of disease emergence and the tendency for trading partners to demand more robust evidence in support of claims for disease freedom. It will also explore the challenges in getting the right sort of surveillance information to the right people at the right time. We face technical, social, economic and political issues that influence the people, policies, programs and information technology that constitute our surveillance system. Many would agree that surveillance is a shared responsibility of governments, livestock industries veterinarians and the wider community; yet we have long struggled to establish a coordinated national approach to surveillance. Against this backdrop of needs and challenges, the presentation will highlight opportunities afforded by modern technologies, the results of social research, shifting paradigms and the implementation of a National Animal Health Surveillance and Diagnostics Business Plan. The presenter will try to provoke discussion on how we might enhance partnerships, find mutual benefits and embrace new technologies to strengthen surveillance and protect the livestock production systems on which so many Australian’s depend

In beef cattle, there are a number of common management practices that result in stress, such as weaning, castration, vaccination, transportation, and commingling.  Despite the source of stress, these activities lead to the activation of the inflammatory reaction, which is initiated by the production of pro-inflammatory cytokines (namely interleukin -1, interleukin-6, and tumor necrosis factor – alpha).  These proteins are the initial instigators of the acute phase reaction, which orchestrates the subsequent production of acute phase proteins and ultimately metabolism alterations impacting feed intake, nutrient utilization, and growth.  Major acute phase proteins in the bovine include haptoglobin and ceruloplasmin, both of which are commonly measured indicators of inflammation. Recent research has revealed links between trace mineral status and impacts on the acute phase protein response of beef calves. These effects appear to have short-term impacts on beef calf productivity, suggesting a direct correlation between trace mineral nutrition and the nutrient-costs related to optimal immune responsiveness.  This presentation focuses on the role of trace mineral nutrition on the acute phase protein reaction and subsequent impacts on performance among newly weaned beef calves.

Much has been published surrounding the impact of Bovine Viral Diarrhoea virus (BVDV) on reproduction and fertility, but there is a paucity of information, under Australian conditions, which describes the effect of exposure to BVDV on production. The impact of BVDV on liveweight gains in weaner calves, and whether vaccination with Pestigard™ (Zoetis Australia) would mitigate against any impact, was assessed in two BVDV endemically infected herds during 2015. This paper describes the serological patterns for BVDV antibody observed in the two herds before, during, and after vaccination, over the nine month duration of the trial. Observations are reported relating to the stability of antibody status within both the vaccinated and control groups, particularly surrounding contact with persistently-infected animals. Implications for herd immunity, and protection status are discussed in view of the reported variations, and some explanations are offered as to how these anomalies may occur. Planning effective control strategies against BVDV, including the use of vaccination, is reviewed in light of the data from these two investigations

Much has been published surrounding the impact of Bovine Viral Diarrhoea virus (BVDV) on reproduction and fertility, but there is a paucity of information, under Australian conditions, which describes the effect of exposure to BVDV on production. The impact of BVDV on liveweight gains in weaner calves, and whether vaccination with Pestigard™ (Zoetis Australia) would mitigate against any impact, was assessed in two BVDV endemically infected herds during 2015. This paper assesses the effect of exposure to pestivirus in either vaccinated or unvaccinated weaner cattle over a nine month period. In one herd, 400 weaners (200 heifers and 200 steers) were weighed on 7 different occasions, while in the 2nd herd 120 heifers were weighed at the beginning and the end of the trial. Comparisons are made between vaccinated and control animals, and by serological status, to more accurately assess any impacts of exposure to pestivirus. Exposure to pestivirus generally had little impact on the growth rate of weaner cattle, contrary to many previous assertions. The implications of the findings are discussed in relation to on-farm control.

Bovine respiratory disease (BRD)is a complex multifactorial disease that occurs commonly in feedlot cattle but is also increasingly being identified as a significant cause of losses in the rearing of dairy calves and in intensive beef grazing systems. Many BRD preventative practices have become commonplace in the absence of adequate supporting data. We will identify those practices for which there is substantial support to assist you in the design of BRD preventative programmes for your clients

After what had been considered the benign presence of the organism in Queensland cattle for more than a century, Bovine anaemia caused by the Theileria orientalis group became an emerging disease of cattle in north-east NSW, with a sharp increase in the number of clinical outbreaks from 2007 onwards. A group of stakeholders met in September 2009 to agree on a national case definition for the condition and extension of available knowledge, to prioritise research directions and projects, and to develop a national education and communication plan. The agreed broad areas of research were: the aetiology and transmission of the disease; the prevalence of the disease, the organism and its vector(s); diagnostics, therapy and economic impact. In the ensuing 6 years, Meat and Livestock Australia funded a suite of research projects into the condition. Molecular diagnostics enabled the discovery that more than one type of T orientalis were present and that the Ikeda type was consistently implicated in cases of clinical disease and was probably a relatively new arrival to the country. Buparvaquone was chosen as a candidate chemotherapeutic and residue assay and depletion data generated. Further research confirmed that Haemaphysalis longicornis was a biological vector of the infection in Australia, but that mechanical transmission by various means could not be ruled out

Producer-funded animal health R&D in Australia is prioritised in part based on the estimated cost of the most important diseases. A survey of cattle and sheep diseases conducted in 2006 had served as a valuable tool for this purpose, but needed updating. A follow-up survey in 2014 estimated the cost of a number of endemic diseases considered to be economically damaging to the red meat industry (cattle, sheep and goats). The survey included producers, processors, government and industry representatives, as well as perusal of available literature. Assumptions of disease distribution, prevalence, production losses and costs of prevention and treatment were analysed in a spreadsheet-based model which estimated individual animal, herd/flock and national costs of each important disease. The 17 diseases of cattle, 23 of sheep and 8 of goats were further assessed in terms of knowledge gaps regarding their aetiology, prevention and treatment, and the threat each one posed in terms of geographic distribution and prevalence

We will build a schematic diagram of the rumen, and the production and utilisation of its fermentative end products. Our discussion will work through the clinical significance of ruminant physiology and biochemistry in the utilisation of the fermentative end products and the utilisation of nutrients that survive passage through the rumen. Biochemistry will be given meaning in a clinical context

Trace minerals, namely copper, selenium, and zinc, have been known to impact immune competence in cattle.  Impacts are associated with innate immune defenses, such as the role of zinc on skin and mucosal barriers, the effects of selenium on phagocytic cell function, and the role of copper and zinc on humoral immune reactions.  Deficiency complications are often associated with calves reared in grazing systems because these essential elements are commonly deficient in grazed forages, particularly warm season forages.  To protect against deficiency, supplementation strategies are required.  In most all production environments, grazing cattle rely upon salt-based, free-choice supplements to supply adequate supplementation and protect against deficiency. This management approach is complicated by several factors among which are the impacts of trace mineral antagonists in grazed forage and the reliance upon predictable, uniform intake of free-choice mineral supplements.  Numerous options are available to assist in the management of trace mineral nutrition of grazing cattle.  This presentation will focus on recent research aimed at the effects of injectable trace minerals on measures of trace mineral status and humoral immune responses of weaned calves

The rumen microbial population constantly changes depending on the feed ingested by the ruminant host. In addition, the rumen itself is a dynamic organ which responds to changes in the composition and total output of volatile fatty acids produced by the rumen microbes. These rumen changes are anatomical, physiological and biochemical. Management of the transition from pasture to concentrate feeds to avoid the development of ruminal acidosis requires matching of volatile fatty acid output from microbial fermentation to the absorptive capacity of the rumen

The results of a research project which established the production losses, direct management costs and opportunity costs associated with fluoroacetate toxicity in grazing cattle in Australia. The project, funded by MLA involved a survey of producers affected by fluoroacetate poisoning in Queensland, Northern Territory and Western Australia, field research in Queensland and the Northern Territory and the preparation of case studies and comprehensive analysis of the financial, management and social impact of fluoroacetate toxicity. Recommendations for management of the impacts of fluoroacetate toxicity based on the results of field and literature research will be presented and discussed. Aims – Facilitate discussion about fluoroacetate toxicity and prospective management approaches designed to reduce the economic, management and social impact of fluoroacetate toxicity

Antimicrobial resistance (AMR) is receiving global interest as an imminent threat, in which common infections could harm or kill again. AMR is also an emerging issue for Australia’s food and agriculture export industries as a potential, new technical barrier to trade. Fighting AMR is one of the strategic pillars for the Australian Veterinary Association and a joint focus of the Australian Government Departments of Agriculture and Water Resources, and Health. So significant is this issue that there have been calls to make AMR a national health or security priority in Australia, as has been done in other countries. The presentation aims to create awareness amongst Australian veterinarians and give a sense of the pace and energy of current international and national drivers, trends and mitigating actions towards AMR in animal and public health sectors. The presentation will also provide an opportunity for individual veterinarians to reflect whether their use of antibiotics could be modified, reviewed or updated in order to reduce the prospect for AMR in Australian animals and the broader community

A field survey conducted in 2015 by NT DPI found that, on average, only 67% of cattle within vaccinated herds were considered protected against botulism. Kelly and Fordyce (2014) suggested that a blood antibody ELISA level over 0.45 was protective against botulinum toxin challenge. This study also found significant differences between vaccine types in reaching this level of protection. The ‘water in oil in water’ adjuvant vaccine provided a higher level of protection than traditional botulism vaccines. Arthington & Havenga (2012) found that concurrent use of a 4-way trace mineral injection with a multivalent modified live respiratory vaccine significantly increased the production of neutralising antibody titres. In the current randomised controlled clinical field trial in QLD, repeat blood samples were taken from weaner cattle that had either received botulism vaccination alone (control) or botulism vaccination and a 4-way trace mineral injection (treatment group). Twenty eight days after vaccination, 90% of the treatment group had reached a botulism antibody titre of 0.45 compared to only 75% in the control group. The mean titre level in the treatment group was 0.96 compared to 0.74 in the control group. These results demonstrate that concurrent use of a 4-way trace mineral injection with a botulism vaccine may assist more cattle in developing protective levels of botulism antibodies

The aetiology and pathogenesis of ruminal acidosis in the well established grain feeding model are related to the occurrence of the condition in ruminants on lush forages. There are strategies to manage the condition with beef cattle placed in feedlots off lush forage, with the management of supplemented pasture based dairy cows, and on an ongoing basis to maximise production off these high quality pastures with various classes of ruminants

Cattle suffering from heat stress have decreased feed intake, hypoglycaemia, decreased fat mobilisation (even with hypoglycaemia), and increased BUN. Peripheral vasodilation also contributes to a loss of GIT integrity which is thought to stimulate an inflammatory cascade driven by lipopolysaccharide and reinforced by leptin which severely exacerbates the chronic metabolic effects. Our developing understanding of the physiological pathways of heat stress allows us to make nutritional interventions to reduce its clinical severity and production effects

Cattle ‘communicate’ their welfare and health through what is referred to as ‘cattle signs’. Cattle signs are parameters that can be observed and measured. The important cattle signs related to nutrition include: behavioural (particularly mentation, hair coat and body language), physiological (particularly appetite, thirst, prehension, erucation, rumination, faecal score, digestibility score, and rumen fill) and management parameters (particularly husbandry). Unfortunately, many signs do not have agreed units of measure or standards. An understanding of conditions and disorders which may cause a sign is crucial for the correct interpretation. For example, cattle (patients) non-ruminating is unusual behaviour and may indicate problems with diet quality. However, the same signs may be observed with abdominal pain, various disorders and stress. The diagnosis of a problem is based on a holistic approach and no individual measure is sufficient. During the assessment of nutrition, the prevalence of a given sign or set of signs need to be established as well at the ‘qualitative’ severity of the sign. This paper will describe how to carry out assessment of the cattle signs and why they are important in assessment of nutrition as part of herd health and productivity management

The rumen fluid obtained by stomach tube or rumenocentesis may provide useful information on the health and function of the digestive and other systems of the bovine patient. Assessment of the rumen content/fluid is essential in diagnosis of disorders of the rumeno-reticulum and disorders blocking the passage of ingesta into the intestines (e.g. pyloric obstruction). Assessment of the sample of rumen fluid should include colour, odour, viscosity, pH, sedimentation, and using some simple laboratory equipment the rumen microbial population and rumen chloride concentration. The normal rumen fluid is of olive-green to greenish-brown colour, slightly viscous, pH of 6.0 to 7.2, sediments in 5-10 minutes and secondary floatation few minutes later. Normal rumen fluid should possess active protozoa visible under low power objective on a warm microscopic slide and should have chloride concentration of

The urine sample obtained by catheterisation, bladder massage, perineal or preputial stimulation and/or free catch may provide useful information of the health and function of the urinary, genital, and other body systems. Urine analysis is an essential step in the evaluation of the primary kidney disorders. For some diagnoses concurrent collection of blood may yield additional information. The assessment of the urine sample can be carried out on farm and in laboratory. The on-farm assessment includes specific gravity, colour, opacity, odour, pH, and presence and quantification of ketone bodies, blood, pigments and protein. Normal urine of cattle patients has specific gravity of 1.020-1.050, is straw-coloured, mildly turbid, with a slight odour on ammonia and has basic pH. Common manifestations of abnormalities for the assessed characteristics of the urine and their interpretation will be briefly discussed. This paper will briefly describe collection of urine sample, on-farm analysis that may be carried out and interpretation of the findings as part of assessment on individual cattle patients

Audits can result in transformational change which can improve clinical practice, business organisation and farm management. Audits measure the value of key performance indicators (e.g. fertility indices) and the quality of processes (e.g. antibiotic selection) and identify the need for change. It is an ongoing cyclical procedure which ensures best current practices are used and outcomes optimised. It provides a mechanism for identifying learning needs and implementing evidence-based clinical and business practice. It is a powerful tool in population medicine and management. It is important to be able to assure clients and peers that the expertise and service offered is safe, effective and efficient. This paper describes how to perform an audit and why it is important in cattle practice

The reproductive performance of dairy herds is affected by multiple factors. While the importance of heat detection efficiency is well recognised for its direct effect on submission rate and pregnancy rate; heat detection accuracy also has the potential to affect a farm’s reproductive performance. Poor heat detection accuracy can affect herd conception rates and embryonic loss. This presentation will look at the ways in which dairy farmers can strategically use cow-side milk progesterone assays to improve heat detection accuracy. The testing of milk progesterone has a potential role in cows eligible for breeding as well as in cows that show oestrous behaviour despite being previously diagnosed pregnant. The benefits and limitations of the use of cow-side milk progesterone assays by farmers will also be discussed

Ovsynch has been commonly used to synchronise lactating cows for fixed-time AI since the 1990s. Since Ovsynch results in a fixed-time AI, the pregnancy rate achieved is usually determined by the conception rate. In a year-round calving herd, lactating cows are often synchronised at the farm’s veterinary herd health visits after a negative pregnancy test or after showing no visible oestrus (NVO). Due to the use of transrectal ultrasound for pregnancy testing, veterinarians can now accurately determine the presence and size of ovarian structures at the time of synchronisation. Together with farm records and disease history, veterinarians have access to a considerable amount of information that can be used to assess the risk of conception. This presentation outlines which factors have an effect on conception rate and discusses treatment options for cows with particular ovarian structures

Previous work had reported on the evidence of anti-Besnoitia besnoiti antibodies in South Australian cattle (Nasir et al. 2012). Testing for B. besnoiti antibodies by PrioCHECK® Besnoitia Ab 2.0 ELISA initially identified 18.4% (95% CI: 15.8–21.0%) of 869 individual cattle sera as positive by ELISA. Additional tests by immunoblot and IFAT, however, could not confirm any of the ELISA results. The use of a higher threshold in the ELISA suggested a way to improve the diagnostic specificity of that assay. There is thus no evidence of B. besnoiti infection in South Australian cattle. Around the same time, there were reports of epistaxis (nose-bleeds) in Western grey kangaroos around Australia and including South Australia that suggested the presence, in the nasal passage of these marsupials, of Besnoitia-like organisms (BLOs). The present study was aimed at characterising those organisms further. Three clinical cases (with epistaxis) were closely examined, as well as serological and molecular assays performed

This talk will give an overview over the research into BVD in our research group over the last few years. At the University of Adelaide’s Roseworthy situated School of Animal and Veterinary Sciences we have worked on Bovine Viral Diarrhoea BVD) for the past years, aiming to improve diagnostic testing protocols, including an attempt to identify the “Trojan” cow carrying a persistently infected (PI) calf in utero. We have improved on the application of diagnostic tests, validated commercially available ELISAs locally and described their performance characteristics on serum and milk, ear notches and pools of samples. We also looked at the feasibility of control efforts in this country and compared their possibility to those successfully carried out in other countries. In addition, we have explored and excluded the possibility of possible additional host reservoirs for the virus in other ruminant hosts, such as sheep, alpaca and buffalo (in the NT)

Certification schemes that aim to provide an assurance on animal welfare have been developed in many countries. As part of a large collaborative project AssureWel, Bristol has been looking at methods to increase the potential welfare impact of schemes. As part of that work we have developed a set of four best practice principles that should help schemes deliver promotion of positive welfare (good life) and limit harms (minimise poor health outcomes). Firstly the scheme can operate a management system that co-ordinates scheme activities which actively promote improvement in animal welfare within participating farms. This management system should include the following generic steps: plan (establish the objectives including desired outcomes, scheme requirements and monitoring processes), do (implement scheme inspection systems and support structures), check (measure and monitor the process and results) and improve (take action to improve performance). Secondly the scheme should develop progressive resources and outcomes requirements that comply with relevant legislation, encourage the provision of opportunities valued by the animals, promote farm level continuous improvement in important welfare outcomes and require innovation not to compromise welfare goals. Thirdly the scheme should target its assessment and support resources on important welfare concerns. Activities should include assessment of relevant welfare requirements and outcomes, promoting interest amongst farmers in their management, ensuring technical advice is available and insisting on remedial action for those farmers with consistent poor outcomes. Finally by taking an evidence-based, participatory and transparent approach the scheme should also embrace external scrutiny and involvement. These principles certification schemes should help schemes adopt a systematic scheme level continuous improvement approach, as already used in quality and environmental certification schemes, to promote improvement at a farm level. These principles could also inform the development of an international agreed standard that could facilitate trade in higher animal welfare products

An understanding of the aetiology of urolithiasis has virtually eliminated the condition in large commercial beef feedlots. However, the condition still occurs in opportunity feedlots and in lamb feedlots. The reasons for this can lie in prior supplementation history and the mineral concentrations of stock water in extensive grazing systems prior to introduction to concentrate feeding, inappropriate diet formulations, the feeding of concentrates separate to roughage, and possibly in extended feeding periods associated with inadequate dietary nutrient density and poor feeding practices