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- Author or Editor: Thomas D. Parsons x
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Abstract
Objective—To determine feeding, cropping, and manure-handling practices of swine operations of various sizes.
Design—Producer survey.
Sample Population—85 sow units and 132 finish floors.
Procedure—Swine producers were surveyed by mail and during farm visits for information regarding herd characteristics and management practices, with emphasis on the 3 components of the nutrient cycle: cropping, feeding and nutrition, and manure handling. Farms were categorized by operation type as sow units or finish floors and, subsequently, stratified by size as small sow units (< 600 head), large sow units (≥ 600 head), small finish floors (< 2,000 head), and large finish floors (≥ 2,000 head).
Results—Large sow units and large finish floors were approximately twice as likely to use environmentally sound nutrient management practices as small sow units or small finish floors. These large operations were more likely to use progressive feeding practices, to be aware of their nutrient flows, and to be capable of using these nutrients properly.
Conclusions and Clinical Relevance—There is a need for greater environmental awareness among all swine producers, especially among small producers. This provides a possible growth area for large-animal veterinary consultants. Economy of scale and increased governmental regulations allow large farms to use environmentally sound practices. Thus, large swine farms are not necessarily harmful to the environment. (J Am Vet Med Assoc 2000;217:1526–1530)
Objective
To identify the preferable testing and vaccination strategy for control of porcine parvovirus (PPV) during a 6-month period.
Design
Decision-tree analysis and computer simulations.
Sample Population
Computer modeling of 300-sow farrow-to-finish herd.
Procedure
Serologic testing of 30 females to estimate herd PPV prevalence versus not testing any females was the initial decision alternative. On the basis of serologic test results, herds were classified into 1 of 3 PPV-risk categories: low (≥ 80% seropositive females), moderate (40 to < 80% seropositive females), or high (< 40% seropositive females). Vaccinating all females, only gilts, or not vaccinating was the second decision alternative.
Results
For initial model assumptions (test sensitivity and specificity = 0.95; test cost = $5/female; vaccination cost = $0.30/dose; vaccination efficacy = 0.95; and foregone gross margin = $10.85/pig), vaccination of all females (with or without serologic testing) was preferable, but the financially preferable option was to omit serologic testing. Most profitable vaccination option varied with foregone gross margin, vaccination cost, and efficacy. For herds in which all sows were known to be immune, vaccinating only gilts was financially preferable, and serologic testing was not warranted. Variation in expected monetary losses was less in vaccination options than with nonvaccination.
Clinical Implications
For most herds in the United States, serologic screening for PPV prior to selection of a vaccination program is unlikely to be cost-effective, because vaccination is inexpensive ($0.30/dose) and effective (95%). At current profit margins ($10.85/pig), vaccination of all females has the least-risk and is the preferred option.
Summary
Medical records of 116 horses admitted to the Texas Veterinary Medical Center between Jan 1, 1984 and Dec 31, 1991 with duodenitis/proximal jejunitis (dpj) were reviewed. The prevalence of laminitis was 28.4% (33/116; 95% confidence interval: 20.2 to 36.6%). The prevalence of dpj and DPJ-associated laminitis did not appear to vary significantly by year during the study period. Anamnesis, physical examination, clinicopathologic data, and initial treatment recorded at the time of admission were reviewed to determine risk factors associated with development of laminitis associated with dpj. A trend of increasing prevalence of laminitis with increasing weight was observed. Using a multiple logistic regression model, horses weighing ≥ 550 kg were approximately twice as likely to develop laminitis than horses weighing < 550 kg (P = 0.048). Horses with hemorrhagic reflux observed at the time of admission were nearly twice as likely to develop laminitis than horses without hemorrhagic reflux (P = 0.022).
Treatments administered prior to admission or at our clinic did not significantly affect development of laminitis, except for administration of heparin to prevent laminitis. Of 33 horses that developed laminitis associated with dpj, 2 had laminitis at the time of admission. These 2 horses were excluded from analysis of the effects of heparin administered as prophylaxis for laminitis; neither horse was treated with heparin. The proportion of horses that developed laminitis among horses that received heparin (0.0%; 0/12) was significantly (P = 0.018) less than that among horses that did not receive heparin (29.8%; 31/104). Because of the small number of horses that received heparin and the retrospective design of this study, the clinical importance of this association could not be determined.
