Stanton PhD Thesis final_docx - Atrium - University of Guelph

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ehavior (Cohn and de Sá-Rocha, 2006). This led to the hypothesis that social status may alter the expression of sickness behavior, especially in confined situations. Anorexia, adipsia and decreased exploratory behavior associated with classic sickness behavior. Where treatment of illness is not available these behaviours are adaptive since they promote energy conservation which is needed for the febrile response (Hart, 1988). However, in modern animal agriculture, where treatment is occurring, this response is often considered to be detrimental to growth and recovery rather than adaptive. These behavioural changes may be especially problematic for calves post-weaning. When individually housed calves are moved to group housing they need to locate and consume feed and water in a novel environment. If their motivation to locate and consume feed and water is reduced due to sickness associated behavioral changes they will likely be unable to maintain adequate nutrient intake. Additionally, water and grain are necessary for continued rumen development (Kehoe et al., 2007) so animals that are anorexic and consuming less water will be slowing the necessary development of their rumen. It has also been hypothesized that the evolutionary role of a species will impact the expression of sickness behavior. Cattle, as prey animals, have been identified as ‘stoic’ in response to pain and disease (Weary et al., 2009). The expression of obvious illness in prey animals is likely to draw predatory attention and increase the risk of the sick animal being targeted. This hypothesis has not been formally tested, but it does raise the important issue regarding the role of species on the expression of sickness behavior and indicates the need for research into species specific sickness behaviors for the detection of disease. 5
In cattle, early disease detection has been identified as a key component of successful disease management. Automated monitoring of health and behavior has been studied for the improvement of disease detection. These automated monitoring systems have been designed in part to overcome the difficulties in identifying sick cattle due to their stoic nature and the decreasing availability of skilled farm labour. Examples of automated disease detection include the use of infrared thermography to detect increased body temperature (Schaefer et al., 2007) and monitoring of eating and drinking (Buhman et al., 2000; Schaefer et al., 2007) in beef calves for the early detection of BRD. In dairy cattle, changes in feeding, drinking, lying and social behavior have been used as early behavioral indicators in cows with a variety of transition diseases including metritis (Huzzey et al., 2007), dystocia (Proudfoot et al., 2009), and subclinical ketosis (Huzzey et al., 2007; Goldhawk et al., 2009; Proudfoot et al., 2009). In dairy calves, automated milk feeder technology has been used to identify sick calves by changes in feeding behavior (Svensson and Jensen, 2007; Borderas et al., 2008; Borderas et al., 2009). These findings have been very useful and have the potential to greatly improve disease detection among group housed, milk-fed dairy calves. However, in the United States 75% of operations house milk-fed dairy calves individually (USDA, 2007); automated feeders are expensive and as such studies that depend on them have limited application for many producers. In addition, these studies do not apply to newly weaned calves , which are also at risk of clinical disease. 1.3 REVIEW OF CURRENT MANAGEMENT PRACTICES TO REDUCE DISEASE In the United States, 97% of dairy calves are separated from their mother within 24 hours of birth (USDA, 2009). After birth, 75% of operations house calves individually, often with minimal physical contact between animals until calves have been weaned from milk-based diets. 6
Page 1 and 2: AN EVALUATION OF THE IMPACT OF MANA
Page 3 and 4: differences in weight gain or calf
Page 5 and 6: 3.2.2 Experimental Study Design 68
Page 7 and 8: 7.4.5 Culling and mortality prior t
Page 9 and 10: Table 6.5: Reasons for death loss a
Page 11 and 12: and season as fixed effects and for
Page 13 and 14: , which requires that “all calves
Page 15: ehaviour of dams challenged with LP
Page 19 and 20: increased rest and decreased appeti
Page 21 and 22: 1.4.2 Nutritional Stressors Dairy c
Page 23 and 24: humans, the metabolic rate increase
Page 25 and 26: Without human intervention, calves
Page 27 and 28: average group size of three or four
Page 29 and 30: al., 2004). Group composition and g
Page 31 and 32: first is the addition of antibiotic
Page 33 and 34: viral diarrhea virus (BVDV) bovine
Page 35 and 36: 1.7 CONCLUSION AND THESIS OBJECTIVE
Page 37 and 38: Buhman, M. J., L. J. Perino, M. L.
Page 39 and 40: Hemsworth, P. H., G. J. Coleman, J.
Page 41 and 42: Schein, M. W. and M. H. Fohrman. 19
Page 43 and 44: Waltner-Toews, D., S. W. Martin and
Page 45 and 46: ehavioural observations ( Borderas,
Page 47 and 48: and had access to ad libitum calf s
Page 49 and 50: may indicate abdominal discomfort,
Page 51 and 52: identified in 5% (40/788) of calves
Page 53 and 54: of diarrhea in calves on this farm
Page 55 and 56: The most common response to the vig
Page 57 and 58: at any observation period. For this
Page 59 and 60: 3 was associated with lower ADG rel
Page 61 and 62: of heifers to allow them to calve a
Page 63 and 64: 2.5 REFERENCES Al-Chaer, E. D. & Tr
Page 65 and 66: Panivivat, R., Kegley, E. B., Penni
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Table 2.2: List of exclusions used
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Table 2.4: The lsmeans ± S.E. of t
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Figure 2.1: Timeline describing tri
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Proportion of calves performing beh
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in a lower rate of vocalizations an
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sites. During the summer months bot
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treatment and weight gain category.
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pre-weaning calf starter intake, an
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Calves spent a total of 13 ± 6 (me
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calves were still allowed access to
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It was hypothesized that the more t
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calves to consume sufficient calf s
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Table 3.1: Descriptive list of obse
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Number of steps per day 7000 6000 5
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Number of lying bouts per day 35 30
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Weight gain (kgs) first 7 days post
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The concept of separating stressors
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were bedded with straw. While house
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4.2.5 Data Collection Calf starter
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4.3 RESULTS enrolment. On average,
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4.3 DISCUSSION There was no effect
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4.4 REFERENCES Chua, B., E. Coenen,
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Steps per day 2500 2000 1500 1000 5
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Appendix 4.1: Scoring sheet used fo
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positive for M. bovis and 4 differe
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feedlots (Van Donkersgoed, 1992). I
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protocol included the identificatio
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(cases) and two calves closest in a
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No statistical analysis was perform
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5.4.3 Growth Three calves returned
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5.4.4 Testing for Mycoplasma Of the
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may be an early sign of respiratory
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small number of unilateral ear droo
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evaluated for efficacy and carefull
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5.6 REFERENCES Biddle, M. K., L. K.
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USDA. 2007. Dairy 2007, part II: Ch
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Table 5.2: Incidence and median age
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Table 5.4: Breakdown of the number
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Figure 5. 5.1: 1: Images taken from
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6.1 ABSTRACT Bovine respiratory dis
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efore entry into the milking herd o
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with bovine viral diarrhea (BVD). O
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6.3.3 Outcome Measures All calves w
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tests, or multiple partial F-tests,
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The effect of treatment on height a
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this study involved continuing with
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is important to emphasize that the
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6.7 REFERENCES J. Carroll and N.E.
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Table 6.1: Disease variables consid
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Table 6.3: Least squares means ( ±
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Table 6.5: Reasons for death loss a
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CHAPTER 7: THE IMPACT OF BOVINE RES
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7.2 INTRODUCTION Bovine respiratory
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days following study enrolment than
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Age at First Calving Since age at f
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(Weaning, Transition, Grower 1, Gro
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The excluded source farm resulted i
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of calves with BRD60 survived to fi
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7.4.8 Milk Production First Test Da
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BRD before 6 months of age decrease
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BRD following movement to group hou
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calves with BRD60 were 1.5 (95% CI:
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7.7 REFERENCES Correa, M. T., C. R.
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Table 7.1: Calving Ease Scoring Sys
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Table 7.3: Least-square means (± S
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Table 7.5: Proportion of calves sur
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Table 7.7: Producers primary reason
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Table 7.9: Effect of BRD60 on calvi
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Table 7.11: Distribution of heifers
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Figure 7.2: Difference in least squ
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Figure 7.4: Time to event analysis
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CHAPTER 8: CONCLUSIONS AND FUTURE R
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Heifers with poor post-weaning grow
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strategic antimicrobial use was met
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Specifically, How can disease sever
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Does transportation, initial social
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