Abatement of Particulate Matter Emission in Broiler Houses Using an Optimized Oil Spraying Method

[EN] In this follow-up study, we investigated effects of two rapeseed oil application rates (8 or 16 mL m-2 d-1) in combination with two spraying frequencies (daily or every other day) in four oil treatments: 8 mL m-2 (24 h)-1, 16 mL m-2 (48 h)-1, 16 mL m-2 (24 h)-1, and 32 mL m-2 (48 h)-1 during two growth cycles of broilers. Oil treatments were randomly assigned to four rooms, whereas two rooms served as control (0 mL m-2). Oil spraying started on day 21. Prior to the second growth cycle, the spraying system was optimized to improve the distribution of oil and reduce the generation of small oil particles. We measured ventilation rate and concentrations of PM10, PM2.5, ammonia, and odor. Furthermore, we recorded bird performance and birds’ exterior quality. PM10 emission was significantly reduced by 59% at 8 mL m-2 d-1 and by 64% at 16 mL m-2 d-1. For PM2.5, these values were 81% and 74%, respectively. In the two every other day treatments, PM10 emission was 44% higher on days after spraying than on spraying days. No significant effect of oil spraying was found on ammonia emission, odor emission, bird performance, and birds’ exterior quality. The latter finding confirms that the incidence of foot-pad lesions is not increased at an application rate of 16 mL m-2 d-1. It is recommended to validate the effects of oil spraying inside full-scale commercial broiler houses at a daily application rate of 16 mL m-2 or less.Winkel, A.; Cambra López, M.; Groot Koerkamp, P.; Ogink, N.; Aarnink, AJA. (2014). Abatement of Particulate Matter Emission in Broiler Houses Using an Optimized Oil Spraying Method. Transactions of the ASABE. 57(6):1853-1864. doi:10.13031/trans.57.10870S1853186457

Gold standards concepts for automatic lameness assessment systems in dairy cows

Lameness is an important welfare problem in modern dairy farms. in order to support lameness control in dairy farms, several concepts to develop a reliable automatic lameness assessment systems (ALAS) have been undertaken. Golden standards methods used for ALAS development are discussed based on a literature review. 16 out of 18 articles related with automatic lameness assessment systems used locomotion scores as gold standard. Main advantages of locomotion scores as gold standard lie on their practical application. Locomotion scores are easy and cheap to use in practice. Disadvantages of locomotion scores as gold standard are related with validity and repeatability of the method. Locomotion scores as tool for pain and hoof lesions (potential source of pain) seems limited because, cows seems to present an important tolerance to pain and locomotion is also impaired by the practical conditions in which it is assessed. Repeatability for locomotion assessment showed a large variation between and within observers. The main factor in the variation of repeatability seems to be the subjectivity associated to locomotion scores. Poor validity and repeatability hinders the interpretation of what is finally being assessed by LSs and ultimately by ALAS. Hoof and painful lesions are also used as gold standard for ALAS development. As Ls diagnosis of hoof and painful lesions are also subjective and may present poor repeatability. In conclusion, currently there is not an optimal gold standard for the development of ALAS.status: publishe

Learning and Experimentation Strategy: Outline of a Method to Develop Sustainable Livestock Production Systems

Over the past decade, the Dutch government has increasingly emphasised the need for integral solutions for sustainability problems in the livestock production sector. This led to the adoption of research approaches in line with transition management and system innovation that had been developed in other domains. In 2008, the government set further policy targets of 5 and 100% sustainable livestock production at the farm level for 2011 and 2023, respectively. Policy measures included stimulation of sector initiatives for sustainable agriculture (sectoral innovation agendas) and demand for projects with a focus on system innovation. Two broad approaches may contribute to the realisation of these targets, notably top-down and bottom-up. Currently, the links between the bottom-up and the top-down processes are relatively weak. As both may contribute to a system innovation, a major challenge is to make a fruitful combination between the two approaches. To this end, we have developed what we call a ‘learning and experimentation strategy’ (LES) that we will elaborate in this chapter