Pen Fouling in Finisher Pigs: Changes in the Lying Pattern and Pen Temperature Prior to Fouling

Pen fouling, where the pigs choose to rest in their designated excretion area (the slatted floors) and excrete in their designated resting area (the solid floors), is an undesired behaviour and should be prevented when possible. One strategy to prevent fouling is early detection by means of either animal or environmental measures changing prior to fouling. The aim of the present study was to investigate whether the lying pattern of pigs and the temperature in the pen changed the last 5 days prior to an event of fouling and whether this differed from pens without an event of fouling (controls). Fouling events was recorded at pen level when at least half of the solid floor was wet with excreta and/or urine (day0). Each fouling pen was paired with a control pen that had not been scored as a fouling pen prior to or at least 1 week after the fouling event. Fouling and control pens were either not provided with straw or provided daily with 150 g of straw per pig. Percentage of pigs lying on the solid floor and the slatted floor (36 events) as well as pen temperature above the solid and slatted floor (24 events) was analysed using four linear mixed effects models. The percentage of pigs lying on the solid floor decreased (40–24%; P < 0.05) while the number of pigs lying on the slatted floor increased (14–24%; P < 0.05) from day-2 to day0 only in the fouling pens, with differences seen between fouling and control pens on the same days (P < 0.01). However, these changes and differences was only seen in pens without straw. Also only in pens without straw did pen temperature above the solid floor decrease from day-2 to day0 (18.6–17.6°C; P < 0.001), with differences seen between fouling and control pens only on day0 (P < 0.05). In contrast, pen temperature measured above the slatted floor did not change, independent of whether the pen was provided with straw or not. Thus, in pens not provided with straw, both the lying pattern of pigs and pen temperature above the solid floor have potential as early detectors of pen fouling

Pen Fouling in Finisher Pigs: Changes in the Lying Pattern and Pen Temperature Prior to Fouling

Pen fouling, where the pigs choose to rest in their designated excretion area (the slatted floors) and excrete in their designated resting area (the solid floors), is an undesired behaviour and should be prevented when possible. One strategy to prevent fouling is early detection by means of either animal or environmental measures changing prior to fouling. The aim of the present study was to investigate whether the lying pattern of pigs and the temperature in the pen changed the last 5 days prior to an event of fouling and whether this differed from pens without an event of fouling (controls). Fouling events was recorded at pen level when at least half of the solid floor was wet with excreta and/or urine (day0). Each fouling pen was paired with a control pen that had not been scored as a fouling pen prior to or at least 1 week after the fouling event. Fouling and control pens were either not provided with straw or provided daily with 150 g of straw per pig. Percentage of pigs lying on the solid floor and the slatted floor (36 events) as well as pen temperature above the solid and slatted floor (24 events) was analysed using four linear mixed effects models. The percentage of pigs lying on the solid floor decreased (40-24%; P < 0.05) while the number of pigs lying on the slatted floor increased (14-24%; P < 0.05) from day-2 to day0 only in the fouling pens, with differences seen between fouling and control pens on the same days (P < 0.01). However, these changes and differences was only seen in pens without straw. Also only in pens without straw did pen temperature above the solid floor decrease from day-2 to day0 (18.6-17.6°C; P < 0.001), with differences seen between fouling and control pens only on day0 (P < 0.05). In contrast, pen temperature measured above the slatted floor did not change, independent of whether the pen was provided with straw or not. Thus, in pens not provided with straw, both the lying pattern of pigs and pen temperature above the solid floor have potential as early detectors of pen fouling.status: publishe

Prediction of Tail Biting Events in Finisher Pigs from Automatically Recorded Sensor Data

Tail biting in pigs is an animal welfare problem, and tail biting should be prevented from developing into tail damage. One strategy could be to predict events of tail biting so that the farmer can make timely interventions in specific pens. In the current investigation, sensor data on water usage (water flow and activation frequency) and pen temperature (above solid and slatted floor) were included in the development of a prediction algorithm for tail biting. Steps in the development included modelling of data sources with dynamic linear models, optimisation and training of artificial neural networks and combining predictions of the single data sources with a Bayesian ensemble strategy. Lastly, the Bayesian ensemble combination was tested on a separate batch of finisher pigs in a real-life setting. The final prediction algorithm had an AUC > 0.80, and thus it does seem possible to predict events of tail biting from already available sensor data. However, around 30% of the no-event days were false alarms, and more event-specific predictors are needed. Thus, it was suggested that farmers could use the alarms to point out pens that need greater attention.status: publishe

Automatic detection of locomotor play in young pigs : A proof of concept

Play behaviour is considered an indicator of animal welfare in young pigs. However, as play behaviour events are short-lasting and occur sporadically, continuous monitoring is necessary. This study presents a first attempt at automatic detection of locomotor play behaviour in young pigs from video by classifying locomotor play from other solitary behaviours including standing, walking, and running. Two methods were developed, compared, and sequentially combined: (1) a less computational heavy method utilising the Gaussian Mixture Model for quantification of movement combined with the calculation of contour features and standard machine learning classifiers (FEATURES); (2) a computational heavy method utilising a deep learning classifier taking both spatial and temporal features into account (DEEP). The DEEP classifier outperformed the FEATURES classifier and obtained values of internal validation recall, precision, and specificity of 94%, 88% and 96%, respectively. When combining the two classification methods, almost similar performance was retained, whilst 44% of the other behaviours were correctly classified without the need for deep learning methods. The combination thereby decreased the computational power needed to run the algorithm. Thus, locomotor play can be automatically detected in young pigs and the combination of a less computational heavy method with a deep learning method can reduce the computational requirements for the classification and detection of complex behaviours. Future work should focus on the segmentation of single pigs during high-speed activity in order to enable the play detection algorithm to work in real-life settings

Influence of temperature during incubation on the mRNA levels of temperature sensitive ion channels in the brain of broiler chicken embryos

Thermosensation is crucial for the survival of any organism. In animals, changes in brain temperature are detected via sensory neurons, their cell bodies are located in the trigeminal ganglia. Transient receptor potential (TRP) ion channels are the largest temperature sensing family. In mammals, 11 thermoTRPs are known, as in poultry, there are only three. This research further elucidates TRP mRNA expression in the brain of broiler embryo's. Three incubation treatments were conducted on 400 eggs each: the control (C) at 37.6 °C; T1 deviating from C by providing a + 1 °C heat stimuli during embryonic day (ED) 15–20 for 8 h a day; and T2, imposing a + 2 °C heat stimuli. After each heat stimuli, 12 eggs per treatment were taken for blood sampling from the chorioallantoic membrane and brain harvesting. Incubation parameters such has residual yolk (free embryonic) weight, chick quality and hatch percentage were collected. After primer optimization, 22 target genes (13 TRPs and 9 non-TRPs) were measured on mRNA of the brain using a nanofluidic biochip (Fluidigm Corporation). Four target genes (ANO2, TRPV1, SCN5A, TRAAK) have a significant treatment effect - independent of ED. Another four (TRPM8, TRPA1, TRPM2, TRPC3) have a significant treatment effect visible on one or more ED. Heat sensitive channels were increased in T2 and to a lesser degree in T1, which could be part of an acclimatisation process resulting in later life heat tolerance by increased heat sensitivity. T2, however, resulted in a lower hatch weight, quality and hatchability. No hormonal differences were detected

Effect of lower temperature stimuli during incubation on fear and social-related behaviours in broilers

Temperature is the most influential environmental parameter during egg incubation affecting embryo development, hatchability and post-hatch performance of broilers. Industrial incubation operates to control the temperature and humidity around the eggs closely based on predefined setpoints and keep fluctuations to a minimum. On the other hand, during brooding, the mother hen regularly leaves the nest for self-maintenance resulting in a striking difference between the constant industrial versus fluctuating natural incubation temperature profiles. Previous studies on ducks and laying hens have found fear and/or social behaviours to be affected by temperatures below recommended values during incubation, a similar result could be existing in commercial broilers. Therefore, this study examines the effect of lowering machine temperatures during incubation on behaviour. Three incubation treatments were defined with a constant machine temperature of 37.6 °C on embryonic day (ED) 0–13 and 19–21 with the machine temperature differing on ED 13–18: (1) Control (C; 37.6 °C), (2) non-optimal Incubation Treatment (IT; 36.6 °C), (3) Natural Treatment (NT, 30 °C for 30 min per day). Post-hatch fear and social behaviour were quantified using six scientifically accepted behavioural tests: three fear tests (novel object on day (d) 1 and d8, tonic immobility (d40), inversion (d42)), two social tests (isolation (d19) and social reinstatement (25)) and one social/fear test (emergence (d18 and d20)). For the emergence test, wherein the time taken for an individual chick to emerge from a T-shaped box was measured, a treatment effect was found on the latency to emerge (P < 0.05) with C chicks emerging more often and faster than IT chicks. As no differences for IT were found in other social tests, the emergence suggest IT chicks to be more hesitant towards novel environments. No differences were present between NT and C or NT and IT. For the isolation test, where an individual chick is visually and audibly isolated for 3 min and the number of vocalisations was measured, an interaction was found between treatment and sex (P < 0.001). Females vocalised more than males in IT and C, but this was not the case for NT. NT male chicks could thus be considered more sensitive to social separation, which could be explained by the higher impact of early stress, caused by the severe temperature drops in NT, having a stronger impact on the anxiety behaviour of males compared to females in later life

Increased temperature during incubation increases the sociality of male broilers in later life

Egg incubation through artificial means is a highly controlled process, where eggs are held at a fixed air temperature of 37.6°C. Nevertheless, much research has been conducted on alternative temperature profiles to evaluate their influence on production and welfare traits. Most attention has been paid on increasing temperature as this had been shown to improve heat tolerance in later life. Limited research has been conducted on the effects on animal behavior, although the absence of negative emotions such as fearfulness and the presence of social expression is considered crucial for positive animal welfare as stated by the Welfare Quality® Protocol for Poultry. Therefore, the objective of the current study was to investigate the effect of two heat tolerance improving thermal treatments: (T1, +1°C and T2, +2°C from embryonic day 15-20) on fearful and social-related behaviors in later life. A total of 12 pens (4 per treatment) containing 13 to 14 chickens was reared for 42 days. During this rearing period, post-hatch fearful and social behavior were quantified using seven behavioral tests: an emergence test, a social reinstatement test, an isolation test, a novel arena test, a novel object test, a human stationary and a human approach test. These tests were chosen based on a thorough literature study and repeated 2 or 3 times. The research results showed that social-related behaviors were affected by the interaction of treatment and gender. Whereas in standard incubation, males have a lower social reinstatement tendency, both treatments changed their behavior. T1 males vocalized more than females during isolation (males: 73 ± 4 calls versus females: 38 ± 2 calls, P<0.001) and T2 males showed more social motivation during a social reinstatement test compared to C (T2: 121 ± 20 sec versus C: 66 ± 25 sec, P<0.05) and T1 (57 ± 27 sec, P<0.05). Finally, an effect of age was found with older birds being less fearful of a novel object and environment, but more fearful of an approaching human. Also, they seem more socially driven to contact conspecifics. However, the validity of these age results is questionable as habituation, changing sensory and/or cognitive skills, variance between repeats and possible reduced mobility at an older age could affect the behavioral response over time. In conclusion, the increased temperature during incubation can improve heat tolerance in later life, however, sociality is also affected. An increased tendency to reinstate contact with conspecifics is found, mainly in males