B. A. Ventura

Effects of barrier perches and density on broiler leg health, fear, and performance

Deterioration of footpad and hock condition and increased stress are important welfare concerns in high-density broiler production. It has been argued that environmental enrichment may help address these issues. We hypothesized that increasing environmental complexity by providing access to barrier perches across a range of densities should improve footpad and hock health, reduce leg fluctuating asymmetry (FA), and mitigate fear in broilers without compromising bird performance. In this study, 2,088 one-day-old broiler chicks were randomly assigned to one of the following barrier and density treatment combinations over 4 replications: simple barrier, complex barrier, or no barrier (control) and low (8 birds/m(2)), moderate (13 birds/m(2)), or high (18 birds/m(2)) density. In wk 7, data were collected on average tibia width and length, FA of tibia width and tibia length, footpad and hock lesions, tonic immobility, feed conversion, final BW, and mortalities. Broilers at higher densities had more severe footpad (P < 0.0001) and hock lesions (P < 0.0001). Their tibias were also longer (P < 0.0001) and less symmetric in length (P < 0.05). The tibias of birds in complex barrier pens were more symmetric in length compared with controls (P < 0.05). Barrier treatment had no effect on hock lesions, although there was a trend for simple barriers to reduce the severity of footpad lesions compared with the control treatment (P = 0.089). Birds kept in simple barrier pens were more susceptible to tonic immobility induction (P < 0.05). Final BW, feed conversion, and mortalities were neither affected by stocking density nor by barrier inclusion. In conclusion, this study shows a negative effect of high density on broiler footpad health and FA. Although barrier perches did not appear to reduce fearfulness, the improvement in footpad health suggests that simple barriers may provide key welfare benefits to broiler chickens.

Access to barrier perches improves behavior repertoire in broilers

Restriction of behavioral opportunities and uneven use of space are considerable welfare concerns in modern broiler production, particularly when birds are kept at high densities. We hypothesized that increased environmental complexity by provision of barrier perches would help address these issues by encouraging perching and enhancing use of the pen space across a range of stocking densities. 2,088 day-old broiler chicks were randomly assigned to one of the following barrier and density treatment combinations over four replications: simple barrier, complex barrier, or control (no barrier) and low (8 birds/m2), moderate (13 birds/m2), or high (18 birds/m2) density. Data were collected on focal birds via instantaneous scan sampling from 2 to 6 weeks of age. Mean estimates per pen for percent of observations seen performing each behavior, as well as percent of observations in the pen periphery vs. center, were quantified and submitted to an analysis of variance with week as the repeated measure. Barrier perches, density and age affected the behavioral time budget of broilers. Both simple and complex barrier perches effectively stimulated high perching rates. Aggression and disturbances were lower in both barrier treatments compared to controls (P<0.05). Increasing density to 18 birds/m2 compared to the lower densities suppressed activity levels, with lower foraging (P<0.005), decreased perching (P<0.0001) and increased sitting (P = 0.001) earlier in the rearing period. Disturbances also increased at higher densities (P<0.05). Use of the central pen area was higher in simple barrier pens compared to controls (P<0.001), while increasing density above 8 birds/m2 suppressed use of the central space (P<0.05). This work confirms some negative effects of increasing density and suggests that barrier perches have the potential to improve broiler welfare by encouraging activity (notably by providing accessible opportunities to perch), decreasing aggression and disturbances, and promoting more even distribution of birds throughout the pen space.

Societal views and animal welfare science: understanding why the modified cage may fail and other stories.

The innovations developed by scientists working on animal welfare are often not adopted in practice. In this paper, we argue that one important reason for this failure is that the solutions proposed do not adequately address the societal concerns that motivated the original research. Some solutions also fail because they do not adequately address perceived constraints within the industry. Using examples from our own recent work, we show how research methods from the social sciences can address both of these limitations. For example, those who persist in tail-docking cattle (despite an abundance of evidence showing that the practice has no benefits) often justify their position by citing concern for cow cleanliness. This result informs the nature of new extension efforts directed at farmers that continue to tail dock, suggesting that these efforts will be more effective if they focus on providing producers with methods (of proven efficacy) for keeping cows clean. Work on pain mitigation for dehorning shows that some participants reluctant to provide pain relief believe that the pain from this procedure is short lasting and has little impact on the calf. This result informs the direction of new biological research efforts to understand both the magnitude and duration of any suffering that result from this type of procedure. These, and other examples, illustrate how social science methodologies can document the shared and divergent values of different stakeholders (to ensure that proposed solutions align with mainstream values), beliefs regarding the available evidence (to help target new scientific research that meets the perceived gaps), and barriers in implementing changes (to ease adoption of ideas by addressing these barriers).

What Difference Does a Visit Make? Changes in Animal Welfare Perceptions after Interested Citizens Tour a Dairy Farm.

Citizens’ concerns about farm animal welfare are often dismissed on the assumption that they are not well informed about farming practices. We conducted exploratory surveys of interested citizens (n = 50) before and after a self-guided tour of a 500-head dairy farm. ‘Before’ survey questions explored perceptions, concerns, and values about dairy cattle farming and welfare, in addition to a short knowledge-based quiz on dairy cattle husbandry. An ‘after’ survey explored the extent to which these constructs shifted after the tour. Before, most participants correctly answered quiz questions about general feeding and housing practices, but scores were low on questions about specific practices such as cow-calf separation. Participants considered several elements as necessary for a ‘good’ life for dairy cattle: fresh food and water, pasture access, gentle handling, space, shelter, hygiene, fresh air and sunshine, social companions, absence of stress, health, and safety from predators. These elements reflect a diverse conception of animal welfare that incorporates values for physical and mental well-being, natural living, and humane care. The visit had a mixed effect on perceptions of whether dairy cows had a ‘good’ life, improving perceptions for a quarter of participants, worsening perceptions in a third, with no shift in the remaining participants. The visit appeared to mitigate some concerns (e.g., provision of adequate food and water, gentle humane care) while reinforcing or eliciting others (e.g., lack of pasture access, early cow-calf separation). Moreover, animal welfare-relevant values held by participants (e.g., natural living, care) appeared to play an important role in influencing perceptions of farm practices. These results suggest that education and exposure to livestock farming may resolve certain concerns, but other concerns will likely persist, especially when practices conflict with deeply held values around animal care.

Mineral balance in horses fed two supplemental silicon sources

Numerous studies suggest that silicon (Si) supplementation is beneficial for mineral metabolism and bone health. Mineral balance studies have not been performed in horses to determine how these supplements affect absorption of other minerals. The purpose of these studies was to investigate the effects of two different Si supplements on mineral absorption and retention in horses. Eight geldings were randomly placed in one of two groups: control (CO) or supplemental Si, which was provided by one of two supplements. The first, sodium aluminium silicate (SA), contains a bioavailable form of Si and is high in aluminium (Al). The second supplement contains oligomeric orthosilicic acid (OSA). All horses received textured feed and ad libitum access to hay. Supplemented horses received either 200 g of SA or 28.6 ml of OSA per day. Following a 10-day adaptation period, the horses underwent a 3-day total collection. Blood samples were taken on days 0 and 13. The two balance studies were conducted 4 months apart to reduce carryover effects. Intakes of Al and Si were greater with SA supplementation (p < 0.05). Sodium aluminium silicate increased faecal and urinary Si excretion (p < 0.05). Calcium retention and apparent digestion were increased by SA (p < 0.05). It also maintained plasma Si compared with the CO which tended to have a decrease in plasma Si (p = 0.08). Supplemental OSA increased retention of Ca and B (p < 0.05) and apparent digestion of B (p < 0.01). Orthosilicic acid tended to increase Si retention (p = 0.054), apparent digestion (p < 0.065), and also increased plasma Si. Both supplements were able to alter Ca retention and B metabolism, however, only OSA was able to alter Si retention, digestibility and plasma concentration. Orthosilicic acid, an Si supplement without substantial Al, appears to be a viable option for Si supplementation as it increased Si retention and digestibility.

The welfare of dairy cattle: perspectives of industry stakeholders

The aim of the current study was to describe the perspectives of stakeholders within the dairy industry on key issues affecting the welfare of dairy cattle. A secondary aim was to examine if these stakeholders believed that people outside of the industry should also have a voice in formulating solutions to these issues. Five heterogeneous focus groups were conducted during a dairy cattle industry meeting in Guelph, Canada in October 2012. Each group contained between 7–10 participants and consisted of a mix of dairy producers, veterinarians, researchers, students, and industry specialists. The 1-h facilitatorled discussions focused on participants’ perceptions of the key welfare issues and the role of different stakeholder groups in addressing these concerns. Discussions were audio-recorded and transcribed verbatim, and the resulting transcripts coded and the themes identified. Lameness was uniformly recognized as the most important welfare issue facing dairy cattle; cow comfort, painful procedures (like dehorning) and production diseases (like mastitis) were also commonly discussed. Participants had mixed views on the roles of different stakeholders in formulating solutions. Most felt that producers and others working within the dairy industry (particularly veterinarians) should be primarily responsible, but many participants acknowledged that the general public, as consumers and as citizens, also play an important role. Participants seemed to focus on a two-fold knowledge deficit - first between researchers and producers, and second between dairy industry groups and the public - and agreed that improved knowledge translation was required to develop solutions to welfare concerns. These results indicate that many people within the dairy industry see value in more inclusive engagement with non-industry stakeholders about dairy cattle welfare. Future work will assess perspectives of people outside of the dairy industry to identify areas of shared concern and provide a basis for policy solutions that better incorporate societal values.