Young broiler feeding kinematic analysis as a function of the feed type

The present study aims to compare the kinematic feeding variables of 3-4 days old broiler chickens using three different feed types: fine mash (F1), coarse mash (F2), and crumbled (F3); size was 476 mu m, 638 mu m, and 1243 mu m, respectively. The head displacement and the maximum beak gape were automatically calculated by computational image analysis to find the feeding behavior of broilers. The results did not show strong correlations between birds' weight, beak size (length and width), and the kinematic variables. The "catch-and-throw" movements in F1 (the smallest feed particle) generally occurred in the first mandibulation, while in F3 (the largest feed particle) occurred in the latest mandibulation. It can be suggested that the adoption of "catch-and-throw" in the latest mandibulations increases with larger particles. Abstract Past publications describe the various impact of feeding behavior of broilers on productivity and physiology. However, very few publications have considered the impact of biomechanics associated with the feeding process in birds. The present study aims at comparing the kinematic variables of young broiler chicks (3-4 days old; 19 specimens) while feeding them with three different feed types, such as fine mash (F1), coarse mash (F2), and crumbled feed (F3). The feeding behavior of the birds was recorded using a high-speed camera. Frames sequences of each mandibulation were selected manually and classified according to the temporal order that occurred (first, second, third, or fourth, and further). The head displacement and the maximum beak gape were automatically calculated by image analysis. The results did not indicate strong correlations between birds' weight, beak size (length and width), and the kinematic variables of feeding. The differences between the tested feed were found mostly in the first and second mandibulations, probably explained by the higher incidence of "catch-and-throw" movements in F3 (33%) and F1 (26%) than F2 (20%). The "catch-and-throw" movements in F1 (the smallest feed particle) mostly occurred in the first mandibulation, as in F3 (the largest feed particle) also occurred in the latest mandibulations. It might be suggested that the adoption of "catch-and-throw" in the latest mandibulations increases with larger particles. The kinematic variables in the latest mandibulations (from the third one on) seem to be similar for all feed types, which represent the swallowing phase. It might be inferred that the temporal sequence of the mandibulations should be essential to describe the kinematics of a feeding scene of broiler chickens, and the first and second mandibulations are potentially the key factors for the differences accounted by the diverse feed particle sizes912CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQsem informaçã

Precision Poultry Farming

This book presents the latest advances in applications of continuous, objective, and automated sensing technologies and computer tools for sustainable and efficient poultry production, and it offers solutions to the poultry industry to address challenges in terms of poultry management, the environment, nutrition, automation and robotics, health, welfare assessment, behavior monitoring, waste management, etc. The reader will find original research papers that address, on a global scale, the sustainability and efficiency of the poultry industry and explore the above-mentioned areas through applications of PPF solutions in poultry meat and egg productio

A behavioural approach to feeding broilers

International audienc

Effect of heat and physiological stress on the growth performance, physiology and welfare of broiler chickens

PhD ThesisBroilers can be faced with a several stressful conditions during their production cycle which can have implications for both growth performance and animal welfare. Animal welfare encompasses the physical and mental well-being of animals, assessed from the biological functioning and subjective experience. The aims of this thesis were i) to develop and validate non-invasive means of assessing the welfare of broilers under physiological and episodic heat stress conditions, ii) to investigate the impact of episodic heat stress, physiological stress and light wavelength on the growth performance, physiology and welfare of broiler chickens and, finally, iii) to investigate a novel means of alleviating heat stress in broilers. Endogenous corticosterone measured in the urate sphere was suppressed by dexamethasone administration. In a cognitive bias task, birds offered mealworms injected with corticosterone to mimic chronic stress were pessimistic in their judgement about ambiguous positions. A positive correlation was established between physiological indicators of stress and cognitive bias. Although light wavelength was confounded with light intensity in our study, there was no difference in growth performance and cognitive ability of birds reared in the blue and red light, except for increased activity of birds in red light. Under simulated episodic heat stress, the change in CBT measured from a temperature-ID chip (ΔCBT-chip) and a data logger (ΔCBT-logger) was positively correlated. Significant positive correlations were found between the change in surface body temperature (SBT) under wing (ΔWT) and ΔCBT-chip, and between ΔWT and ΔCBT-logger. Significant positive regression equations relating change in CBT and RR with apparent equivalent temperature (a factor which combines environmental temperature and RH) were also developed. High temperature coupled with high RH aggravated the respiratory rate (RR) of broilers and this was accompanied by suppression of peening behaviour. High heat stress for 3 hours had a greater impact on birds than moderate heat stress for 6 hours. For broilers exposed to moderate heat stress, the provision of additional cup drinkers reduced the rise in CBT and the proportion of time spent in wing drooping behaviour, but enhanced SBTs suggesting increased heat dissipation.Federal University of Agriculture, Abeokuta, Ogun state, Nigeri

Using naturally-occurring variation in beak morphology to reduce feather pecking damage in laying hens

Outbreaks of severe feather pecking continue to be a serious welfare and economic concern for the poultry industry, particularly within the egg sector. Increasing consumer awareness of how poultry is raised and managed has led to a shift from cage systems to loose-housed ‘alternative’ systems, increasing the risk of outbreaks. Severe feather pecking, a form of injurious pecking, is commonly observed in laying hen flocks and can lead to cannibalism and high mortality. As a result, research has increasingly focused on how best to prevent and control severe feather pecking without needing beak treatment (an effective method of reducing physical damage caused by severe feather pecking and is commonly performed at day-old using infrared energy). Alternative practices to beak treatment include genetic selection against the behaviour itself, using enrichment materials to encourage appropriate foraging behaviour, and genetic selection of traits related to the behaviour (i.e., feather cover, liveability, and beak shape). This project examined the possibility of using genetic selection of beak shape to reduce damage inflicted by severe feather pecking. Significant beak shape variation exists within and between breeding laying hen lines, and research has shown that aspects of beak shape are heritable. This suggests incorporating beak shape data into selection indices is possible; however, characterisation of beak phenotypes and the amount of physical damage different beak shapes can cause is first needed. The shapes of the premaxillary and dentary bones within the beak have also never been characterised before in laying hens. Examining the bone shape is important as it has been suggested that it may influence the external beak shape to a certain extent. A pilot study was performed to determine if the analysis of the beak and its underlying bone shape defined and quantified by geometric morphometrics (GMM) of radiographic images was repeatable. Twenty-four hens were radiographed four times. Repeatability ranged from 0.52 to 0.81, demonstrating that imaging live hens over time and landmarking those images was repeatable. Using radiography and GMM, a study was conducted to characterise the variation in premaxillary and dentary bone shape within two pure lines of White Leghorn laying hens. Premaxillary bone shapes ranged from long and narrow with pointed bone tips to short and wide with more curved bone tips. Dentary bone shapes ranged from long and wide to short and narrow. For both bones, the shape differed between the two lines, and the size of the bone significantly affected its shape. The results showed that a range of shape phenotypes exist for both the premaxillary and dentary bone, which may influence beak shape. Photographs of the two pure lines were also taken to analyse the beak shape using GMM and examine the relationship between beak shape, the underlying bone shape, feather cover, and mortality. Maxillary beak shapes ranged from long and narrow with pointed beak tips to short and wide with more curved beak tips. The maxillary beak was moderately correlated to the premaxillary bone in shape and size. The shape data suggest distinct beak and bone phenotypes within each line for the beak and its underlying bones. In addition, feather cover and mortality differed between the two lines, with one line having better feather cover and lower mortality over the 100-week production cycle. Therefore, beak shape may be one factor contributing to the differences seen in feather cover and mortality. These distinct phenotypes could be selected to help reduce damage inflicted by severe feather pecking and improve laying hen welfare. Two studies were conducted to understand and quantify the physical damage different beak shapes can cause. The first study used live hens with either a sharp or blunt beak that pecked at “chicken” models (foam blocks covered with feathered chicken skin). The change in block and skin weight, the number of feathers removed from the skin, and the number of successful (resulting in feather or tissue removal) versus non-successful (no removal) pecks at the model were recorded. The change in block weight did not differ between the two groups; however, the sharp beak group had a larger change in skin weight and removed significantly more feathers than the blunt group. The mean number of pecks made at the model also did not differ between the beak shape groups; however, sharp beak hens had a greater percentage of successful pecks, while blunt beak hens had a greater percentage of non-successful pecks. The results of this study show that sharp beak hens were more capable of removing feathers and, by extension, tissue, thus resulting in damage. The second study used a robotic device to mimic a hen’s natural pecking motion ex vivo. Using this device, chicken heads pecked into agarose gel, which mimics muscle, at three pecking forces. The depth and volume of the indentations into the gel were assessed to quantify damage. No differences in indentation depth or volume were found between the different beak shape groups. Pecking force did affect depth and volume; however, the results were inconsistent. The results of this study suggest that the beak shapes tested were perhaps too similar to discern differences. These two studies also suggest other factors beyond beak sharpness (i.e., the curvature of the maxillary beak over the mandibular beak), such as other beak shape characteristics or the motivation to perform the behaviour, contribute to feather removal and tissue damage. This project’s results show that specific beak phenotypes within laying hen breeding lines could be incorporated into selection indices. This project provides a foundation for future genetic and behavioural research investigating the effect of beak shape on other beak-related behaviours like feeding and preening and identifying quantitative trait loci that underlie beak shape. More research is needed to examine the relationship between beak shape and its capacity to cause damage

The Effects of Light Intensity During Rearing on Brown- and White-Feathered Egg Strain Pullets’ Use of Space, Behaviour, and Health

This study aimed to determine the effects of light intensity (L) and strain (S) on growth, behaviour, frequency and success of jumping between structures, bone health, and welfare of pullets reared in a perchery. Three L (10, 30, or 50 lux, provided by white LED lights) and two Lohmann S (Brown-Lite (LB) and LSL-Lite (LW)) were tested. Pullets were floor reared in pens within light tight rooms from 0 to 16 weeks of age (wk). Each pen contained a system of four parallel perches, a ramp, drinker line, and two tube feeders. Data collected included body weight (BW), behaviour, jumping frequency and success, fear and stress response, keel bone damage (KBD), breast muscle weight, tibia bone characteristics and strength, and mortality. L did not affect BW, aggression, jumping success, fear, stress, KBD, breast muscle weight, tibia bone characteristics and strength, or mortality. At 13 and 16 wk, pullets reared in 50 lux spent more time preening than 10 lux pullets. At four wk, pullets reared in 30 and 50 lux had higher jumping frequency than 10 lux pullets, however jumping success did not differ. LB pullets had a higher BW than LW pullets at eight and 16 wk. Throughout the experiment, LB pullets spent more time pecking at litter and walls than LW pullets, while LW pullets spent more time resting and preening. LW pullets performed more jumps than LB pullets and were equally as successful in navigational jumps. S did not affect aggression, however LB pullets had higher fear and heterophil/lymphocyte ratio, suggesting S characteristic differences. S did not affect KBD. LB pullets had heavier breast muscle and tibia, however LW pullets had a proportionally higher breast muscle yield and thicker and stronger tibia. Mortality was higher in LW pullets than LB pullets in the first wk. The results suggest that pullets could navigate their environment safely under the Canadian industry standard of 10 lux. Higher L at 30 or 50 lux may have a minor improvement on welfare by increasing bird activity. Conclusively, these light intensities can prepare pullets for navigating complex environments during the laying phase