Cost effective combined axial fan and throttling valve control of ventilation rate

This paper is concerned with Proportional-Integral-Plus (PIP) control of ventilation rate in mechanically ventilated agricultural buildings. In particular, it develops a unique fan and throttling valve control system for a 22m3 test chamber, representing a section of a livestock building or glasshouse, at the Katholieke Universiteit Leuven. Here, the throttling valve is employed to restrict airflow at the outlet, so generating a higher static pressure difference over the control fan. In contrast with previous approaches, however, the throttling valve is directly employed as a second control actuator, utilising airflow from either the axial fan or natural ventilation. The new combined fan/valve configuration is compared with a commercially available PID-based controller and a previously developed scheduled PIP design, yielding a reduction in power consumption in both cases of up to 45%

Frequency analysis of vocalisations in relation to the growth in broiler chicken

Poultry is one of the lowest cost sources of animal protein in the world and, more than 40 billion chickens are produced every year globally. For reasons of public concern and due to the large number of animals involved, it is considered by many people to be important to take care of the welfare and health status of the chickens reared under intensive farm conditions. Precision Livestock Farming (PLF) can support the farmer in his day to day routine management through the use of sensors, cameras and microphones, and these have the potential to improve production and to enable monitoring of welfare status. In this context, the 7FP EU-PLF project aims to test the efficiency of the use of those sensors at farm level. In particular, the aim of this study was to record and analyse broiler vocalisations under normal farm conditions and to identify the relation between animal sounds, and growth trends. Recordings were made at regular intervals, for the entire short production life of the birds, in order to evaluate the variation of frequency and bandwidth of the sounds emitted by the animals during the cycle of production. The recordings were made in an automated, non-invasive and non-intrusive way and the sound data was compared with the weight of the birds automatically measured by a 'step on scale' placed on the floor of the broiler house. Sound analysis was performed based on the amplitude and frequency of the sound signal in audio files recorded at farm level. Through analysis of the sounds recorded, a significant correlation (P<0.001) between the frequencies of the vocalisations recorded and the weight of the broilers was found across all production cycles and farms assessed. The ongoing goal will be the development of a tool able to automatically detect the growth of the animals based on the frequency of the vocalisation emitted by the birds at different ages, and as a possible tool for determining deviations from their expected growth trend

Automated real-time stress monitoring of police horses using wearable technology

Mounted police horses and riders are repeatedly subjected to demanding and stressful situations. Intensive selection and training of police horses is required to ensure performance, safety and welfare of the horses and their riders. At the mounted police in Brussels, Belgium, the selection of police horses is mainly based on intuition built upon previous experience which makes it a subjective decision. Although this decision mostly leads to good results, sometimes horses are purchased that turn out to be unsuited for the mounted police. Including an objective measure when evaluating the longer term suitability of candidate police horses could help the mounted police to further improve their selection procedure for police horses. This study investigated the potential of real-time stress detection as a measure to evaluate the longer term suitability of police horses. Four experimental protocols were developed in consultation with the mounted police and were performed by 17 horse-rider pairs. The horses were divided into four categories according to their experience and suitability as police horses: good beginner, bad beginner, good experienced and bad experienced. The relative stress of the horses was monitored with wearable technology during every protocol. For one protocol, the time percentage spent over 20% relative stress by the horse was found to be significantly lower for good compared to bad beginner horses (p-value = 0.0277). In conclusion this study demonstrated that real-time stress detection with wearable technology in mounted police horses provides information on the longer term suitability of police horses

Higher levels of CO2 during late incubation alter the hatch time of chicken embryos

status: publishe