David C J Main

The development, implementation and testing of a lameness control programme based on HACCP principles and designed for heifers on dairy farms

This paper describes the development and testing of a lameness control programme (LCP) for heifers on dairy farms. The LCP, which is based on the analysis of hazards and critical control points (HACCP), was tested via a randomised intervention study on 60 farms. Tangible hazards for each farm were identified, allotted to 11 categories of proximate hazard and scored on each farm to quantify the risks presented by each hazard. Feet were inspected for signs of claw horn disease and infection, such as digital dermatitis. Intervention was generally ineffective, primarily through failure to implement the LCP. However, retrospective analysis was able to demonstrate highly significant associations between risks attached to proximate hazards and probabilities of lameness and foot lesions, allowing the severity of these hazards to be ranked. The most significant proximate hazards of environmental origin were prolonged standing on concrete, standing in wet slurry and factors that cause claw trauma. The most severe proximate hazards however were those associated with failures of management, especially poor claw condition and inadequate foot care. Overall farm risks (OFR) were estimated by summing the products of the generic severity for proximate hazards with on-farm risks. Changes in OFR were significantly related to changes in outcome (lameness and lesions).

Quality Assurance Schemes

This paper considers the consumers changing definition of quality in relation to meat and the current development of Quality Assurance (QA) schemes to ensure that certain quality standards are met. The key ingredients of QA schemes are food safety, animal welfare and sensory aspects (meat quality) although the latter is not a major feature of many schemes at present. For each of these components, points in the production-processing chain where problems can arise should be identified and control procedures introduced. Monitoring is required to check the effectiveness of these. This approach is based on HACCP principles although best practice rules are the basis of most current QA schemes. The paper identifies key points on the farm and in the abattoir where food safety, animal welfare and meat quality can be compromised and shows how best practice procedures are introduced to reliably raise standards. There is some concern about the credibility of some QA schemes in relation to the standards set, the strictness of inspection and especially the impartiality of auditing procedures. This may be ensured in schemes within Europe which comply with EN 45011 standards. The move towards more tightly regulated QA schemes to raise consumer confidence could benefit some traditional products and organic meat production schemes which already operate with strict specifications.

Assessment of the behaviour and welfare of laying hens on free-range units

The aims of this study were twofold: to develop and test an animal-based protocol for the assessment of the physical and emotional elements of the welfare of laying hens on free-range units and to investigate the effects of different approaches to housing and management on the welfare of the birds. The protocol was tested on 25 free-range units for laying hens, each of which was visited on four occasions by one of five trained observers; further information about husbandry, health and productivity was gathered from interviews with the farmers. Measures of the birds attitude included arousal, noise, flight distance and response to a novel object, measures of their activity included feather pecking, aggression and use of range, and measures of their physical welfare included mortality, body condition and egg quality. Increased arousal was associated with increased flight distance, greater reluctance to approach a novel object and higher levels of feather pecking and feather loss, but the correlation between pecking and feather loss was low. The birds maintained body condition throughout the period of lay. Neither body condition, feather pecking nor feather loss was affected by the extent of beak trimming. Estimated losses (deaths and culls) ranged from 1·8 to 21·4 per cent (median 6·95 per cent). Few birds showed signs of ill health, limb lesions or red mite infestation. No feature of building design had a significant effect on mortality, but there were consistent differences in the birds attitude, behaviour and performance attributable to the type of floor and the presence or absence of perches, which suggested that the welfare of the hens was inferior when they were housed on plastic floors with no perches.

Evaluating an intervention to reduce lameness in dairy cattle

Lameness in dairy cattle remains a significant welfare concern for the UK dairy industry. Farms were recruited into a 3-yr study evaluating novel intervention approaches designed to encourage farmers to implement husbandry changes targeted toward reducing lameness. All farms completing the study were visited at least annually and received either monitoring only (MO, n=72) or monitoring and additional support (MS, n = 117) from the research team. The additional support included traditional technical advice on farm-specific solutions, facilitation techniques to encourage farmer participation, and application of social marketing principles to promote implementation of change. Lameness prevalence was lower in the MO (27.0 ± 1.94 SEM) and MS (21.4 ± 1.28) farms at the final visit compared with the same MO (38.9 ± 2.06) and MS (33.3 ± 1.76) farms on the initial visit. After accounting for initial lameness, intervention group status, and year of visit within a multilevel model, we observed an interaction between year and provision of support, with the reduction in lameness over time being greater in the MS group compared with the MO group. Farms in the MS group made a greater number of changes to their husbandry practices over the duration of the project (8.2 ± 0.39) compared with those farms in the MO group (6.5 ± 0.54). Because the lameness prevalence was lower in the MS group than the MO group at the start of the study, the contribution of the additional support was difficult to define. Lameness can be reduced on UK dairy farms although further work is needed to identify the optimum approaches.

Herd health planning: farmers' perceptions in relation to lameness and mastitis

Between December 2002 and December 2003, the herd health planning activities on 61 dairy farms in the uk were compared with several measures of lameness and mastitis. Lameness had been reported as a problem in 53 of the herds directly by the farm and in the other eight by the nominating local veterinary practice; 54 of the farms also reported having a mastitis problem. Fifty-three (87 per cent) of the farms had some form of written herd health plan, of which 21 (40 per cent) had been in place for 12 months or less. All the farms were recording mastitis in some way, although 38 (62 per cent) of the farmers did not review these records and only four retained the results of a comprehensive record review. Farms defined as having a high incidence of mastitis were more likely to be reviewing their health records, but farms defined as having a high prevalence of lameness in a sentinel group of early lactation heifers were less likely to be reviewing their health records.

Measuring the response to therapeutic foot trimming in dairy cows with fortnightly lameness scoring

Lameness scoring (0-3) was carried out on four UK dairy farms during the housing period over three consecutive years (2010-2012). At the start of the study cows were matched by parity and stage of lactation and randomly allocated into a treatment (TX) and a control (CX) group. Cows were enrolled when two sound scores (0 or 1) were followed by a lame score (2). Farmers were immediately notified of score 3 cows, which were then excluded from the study, irrespective of whether they were in treatment or control groups. The animals in the TX group received treatment 3-48 h after being scored lame. Farmers remained blind to the treatment group. Throughout the study the participating farmers continued to identify and treat lame cows according to their usual approaches, this included treating animals in the CX or TX group if they so chose. The fortnightly lameness scoring and treatment of the TX group resulted in higher cure rates at each scoring session following treatment when compared with the CX group (Pu2009<u20090.001). Two weeks after inclusion, 78% (SEu2009 ±u2009 3.2) of TX cows were sound, compared with 66% (SE u2009± u20093.1) of CX cows. At 18u2009 weeks following initial recruitment this had fallen to 41% (SE u2009± u20096.3) (TX) and 13% (SE u2009±u2009 4.7) (CX). The percentage of total scores which were sound scores in the TX and CX groups following inclusion in the trial was 81% and 66.1%, respectively (Pu2009<u20090.001). The main lesions found on treatment in the TX group were sole haemorrhage (41% of cases) and digital dermatitis (33%). Severe lesions (sole ulcers and toe necrosis) were only found in 6.6% of cases. In the treated CX animals the percentage of severe lesions was 14%.

Navigating the iceberg: reducing the number of parameters within the Welfare Quality(®) assessment protocol for dairy cows.

The Welfare Quality(®) protocols provide a multidimensional assessment of welfare, which is lengthy, and hence limited in terms of practicality. The aim of this study was to investigate potential iceberg indicators which could reliably predict the overall classification as a means of reducing the length of time for an assessment and so increase the feasibility of the Welfare Quality(®) protocol as a multidimensional assessment of welfare. Full Welfare Quality(®) assessments were carried out on 92 dairy farms in England and Wales. The farms were all classified as Acceptable or Enhanced. Logistic regression models with cross validation were used to compare model fit for the overall classification on farms. Absence of prolonged thirst, on its own, was found to correctly classify farms 88% of the time. More generally, the inclusion of more measures in the models was not associated with greater predictive ability for the overall classification. Absence of prolonged thirst could thus, in theory, be considered to be an iceberg indicator for the Welfare Quality(®) protocol, and could reduce the length of time for a farm assessment to 15 min. Previous work has shown that the parameters within the Welfare Quality(®) protocol are important and relevant for welfare assessment. However, it is argued that the credibility of the published aggregation system is compromised by the finding that one resource measure (Absence of prolonged thirst) is a major driver for the overall classification. It is therefore suggested that the prominence of Absence of prolonged thirst in this role may be better understood as an unintended consequence of the published measure aggregation system rather than as reflecting a realistic iceberg indicator.

Implementing Welfare Quality® in UK assurance schemes: evaluating the challenges

This paper presents an account of a Welfare Quality® assessment of 92 dairy farms carried out by seven experienced assessors. The aim was to evaluate the potential of the Welfare Quality® assessment protocol with respect to its uptake by UK farm assurance schemes. Data collection, and measure aggregation were performed according to the Welfare Quality® protocol for dairy cows. This study examined the data itself, by the testing of how hypothetical interventions might be reflected in changes in the aggregated scores, and also investigated human-related aspects, through inter-assessor standardisation sessions to evaluate reliability, and an assessor focus group to collect feedback. Overall, three main ‘challenges’ were identified. The first challenge related to the large amount of missing data. Unexpectedly, this was such that it was only possible to calculate an overall classification for 7% of farms. The second challenge concerned the way in which aggregated scores did not always reflect hypothetical interventions. The final challenge was inter-assessor reliability, where not all assessors were found to achieve acceptable levels of agreement on a number of outcome measures by the third training session. Suggestions for managing these challenges included, follow-up to assessor training, the use of multiple imputation methods to fill in missing data, and, where applicable, not aggregating the scores. The conclusion of the study was that the protocol provided useful information from which to make an informed selection of measures, but that the challenges, combined with the lengthy assessment time, were too great for its use as a certification tool.

Application of Welfare Assessment to Commercial Livestock Production

Farm assurance schemes are an inevitable and essential part of the UK livestock industries as they provide valuable assurances to the market over food safety, nonhuman animal welfare, and environmental concerns. However, there is potential for welfare assessment within such schemes to extend beyond existing resource-based parameters to include outcome-based observations of the behavior and physical condition of the animal. This may be associated with direct benefits for producers (useful management information), consumers (improved welfare assurance), industry (maintain UK competitive position), and regulators (maximize compliance with legislation). The University of Bristol has previously produced protocols to assist with this process (www.vetschool.bris.ac.uk/animalwelfare). An industry-funded project explores mechanisms for adding value to farm assurance schemes by inclusion of on-farm evaluation of health and welfare outcomes. This project is examining the feasibility and benefits of including some on-farm observations of health and welfare outcomes.

Welfare outcomes assessment in laying hen farm assurance schemes

Most farm assurance schemes in the UK at least, in part, aim to provide assurances to consumers and retailers of compliance with welfare standards. Inclusion of welfare outcome assessments into the relevant inspection procedures provides a mechanism to improve animal welfare within assurance schemes. In this study, taking laying hens as an example, we describe a process for dealing with the practical difficulties in achieving this in two UK schemes; Freedom Food and Soil Association. The key challenges arise from selecting the most appropriate measures, defining sampling strategies that are feasible and robust, ensuring assessors can deliver a consistent evaluation and establishing a mechanism to achieve positive change. After a consultation exercise and pilot study, five measures (feather cover, cleanliness, aggressive behaviour, management of sick or injured birds, and beak trimming) were included within the inspection procedures of the schemes. The chosen sampling strategy of assessing 50 birds without handling provided reasonable certainty at a scheme level but less certainty at an individual farm level. Despite the inherent limitations within a time and cost sensitive certification assessment, the approach adopted does provide a foundation for welfare improvement by being able to highlight areas of concern requiring attention, enabling schemes to promote the use of outcome scoring as a management tool, promoting the dissemination of relevant technical information in a timely manner and increasing the scrutiny of standards important for the welfare of the birds.