Promoting health and welfare in organic laying hens. Recommendations to ensure hen health and welfare in organic husbandry

In the HealthyHens project we investigated laying hen health and welfare in organic poultry systems in eight European countries. This leaflet presents our findings and recommendations. Most of our recommendations are also relevant for conventional poultry systems

Recycling manure as cow bedding: potential benefits and risks for UK dairy farms

Material obtained from physical separation of slurry (recycled manure solids; RMS) has been used as bedding for dairy cows in dry climates in the US since the 1970s. Relatively recently, the technical ability to produce drier material has led to adoption of the practice in Europe under different climatic conditions. This review collates the evidence available on benefits and risks of using RMS bedding on dairy farms, with a European context in mind. There was less evidence than expected for anecdotal claims of improved cow comfort. Among animal health risks, only udder health has received appreciable attention. There are some circumstantial reports of difficulties of maintaining udder health on RMS, but no large scale or long term studies of effects on clinical and subclinical mastitis have been published. Existing reports do not give consistent evidence of inevitable problems, nor is there any information on clinical implications for other diseases. The scientific basis for guidelines on management of RMS bedding is limited. Decisions on optimum treatment and management may present conflicts between control of different groups of organisms. There is no information on the influence that such 'recycling' of manure may have on pathogen virulence. The possibility of influence on genetic material conveying antimicrobial resistance is a concern, but little understood. Should UK or other non-US farmers adopt RMS, they are advised to do so with caution, apply the required strategies for risk mitigation, maintain strict hygiene of bed management and milking practices and closely monitor the effects on herd health

Inter-rater reliability of categorical versus continuous scoring of fish vitality: does it affect the utility of the reflex action mortality predictor (RAMP) approach?

Scoring reflex responsiveness and injury of aquatic organisms has gained popularity as predictors of discard survival. Given this method relies upon the individual interpretation of scoring criteria, an evaluation of its robustness is done here to test whether protocol-instructed, multiple raters with diverse backgrounds (research scientist, technician, and student) are able to produce similar or the same reflex and injury score for one of the same flatfish (European plaice, Pleuronectes platessa) after experiencing commercial fishing stressors. Inter-rater reliability for three raters was assessed by using a 3-point categorical scale (‘absent’, ‘weak’, ‘strong’) and a tagged visual analogue continuous scale (tVAS, a 10 cm bar split in three labelled sections: 0 for ‘absent’, ‘weak’, ‘moderate’, and ‘strong’) for six reflex responses, and a 4-point scale for four injury types. Plaice (n = 304) were sampled from 17 research beam-trawl deployments during four trips. Fleiss kappa (categorical scores) and intra-class correlation coefficients (ICC, continuous scores) indicated variable inter-rater agreement by reflex type (ranging between 0.55 and 0.88, and 67% and 91% for Fleiss kappa and ICC, respectively), with least agreement among raters on extent of injury (Fleiss kappa between 0.08 and 0.27). Despite differences among raters, which did not significantly influence the relationship between impairment and predicted survival, combining categorical reflex and injury scores always produced a close relationship of such vitality indices and observed delayed mortality. The use of the continuous scale did not improve fit of these models compared with using the reflex impairment index based on categorical scores. Given these findings, we recommend using a 3-point categorical over a continuous scale. We also determined that training rather than experience of raters minimised inter-rater differences. Our results suggest that cost-efficient reflex impairment and injury scoring may be considered a robust technique to evaluate lethal stress and damage of this flatfish species on-board commercial beam-trawl vessels

The use of the antennae in tactile obstacle localisation in the walking stick insect

Dürr V, Brenninkmeyer C. The use of the antennae in tactile obstacle localisation in the walking stick insect. In: Proc.Congr.Int.Soc.Neuroethol. Vol 6. 2001: 263-263

Gastrointestinalhelminthosen bei Legehennen in deutschen Öko-Betrieben

Ziel einer Querschnittsstudie war es, die bislang spärlichen Erkenntnisse über den Endoparasitenbefall bei Legehennen in ökologisch geführten Betrieben Deutschlands zu erweitern. Die Studiendurchführung erfolgte im Rahmen des europäischen Forschungsprojekts “HealthyHens“. In sieben Öko-Betrieben wurden jeweils 15 Legehennen (Lohmann Brown oder TetraSL) kurz vor Ende ihrer Legeperiode (ca. 70. Lebenswoche) mittels helminthologischer Teilsektion (Magen-Darm-Trakt) untersucht; Zestodenexemplare wurden zusätzlich molekularbiologisch (rRNA-Gene) charakterisiert. Die über Deutschland verteilten Betriebe unterschieden sich u.a. in Haltungsform (Boden- oder Volierenhaltung, jeweils mit Grünlandauslauf), Größe (500–30.000 Legehennenplätze, z.T. an mehreren Standorten) und Besatzdichte in Stalleinheiten (4,3–6,8 Hühner/m2); als “Wurmmittel“ wurden überwiegend nur pflanzliche Stoffe (Kräutermischungen, Oregano) verwendet, auf einem Betrieb kam Flubendazol zum Einsatz. Infektionen mit Ascaridia galli und Heterakis gallinarum waren in allen Betrieben (innerbetriebliche Prävalenz (IP): 87–93 % bzw. 60–100 %;), mit Capillaria spp. und Raillietina cesticillus in sechs (IP: 53–100 %) bzw. vier Betrieben (IP: 7–73 %) nachzuweisen; weitere Gastrointestinalhelminthenarten wurden nicht festgestellt. Die Stärke des Ascaridia-Befalls (innerbetriebliche mittlere Abundanz (IMA): 3,3±2,7–55,7±70,0 Würmer) unterschied sich zwischen den Betrieben nicht signifikant, jedoch gab es zwischen den Betrieben signifikante Unterschiede (Kruskal-Wallis-Test mit nachfolgenden multiplen Vergleichen nach Dunn) in der Stärke des Heterakis-Befalls (IMA: 30,0±27,5–121,4±84,6 Würmer). Die Ergebnisse legen nahe, dass Helminthenbefall in ökologisch geführten Legehennenbetrieben zu erwarten ist, seine artliche Zusammensetzung sowie die Befallshäufigkeit und -stärke aber variiert. Daher sollte eine Helminthenbekämpfung zur Verbesserung der Tiergesundheit nicht pauschalen Empfehlungen folgen, sondern vielmehr auf die jeweilige Betriebssituation bezogen durchgeführt werden. Wir bedanken uns für die Förderung des Projekts durch die BLE im Rahmen des CORE Organic II Programms (www.coreorganic2.org)

Feather-pecking and injurious pecking in organic laying hens in 107 flocks from eight european countries

Feather-pecking and cannibalism may reduce the potential of organic husbandry to enhance the welfare of laying hens. We report risk factors for these issues based on a large survey of 107 commercial flocks in eight European countries. Information was collected regarding housing, management and flock characteristics (age, genotype). Near the end of lay, 50 hens per flock were assessed for plumage condition and wounds. Potential influencing factors were screened and submitted to a multivariate model. The majority of the flocks (81%) consisted of brown genotypes and were found in six countries. Since white genotypes (19%) were found only in the two Scandinavian countries, a country effect could not be excluded. Therefore, separate models were made for brown and white genotypes. Feather damage in brown hens could be explained by a model containing a lower dietary protein content and no daily access to the free range (30% of the variation explained). For feather damage in white hens, no model could be made. Wounds in brown hens were associated with not having daily access to free range (14% of the variation explained). Wounds in white hens were explained by a model containing not topping-up litter during the laying period (26% of the variation explained). These results suggest that better feeding management, daily access to the free-range area and improved litter management may reduce incidence of plumage damage and associated injurious pecking, hence enhancing the welfare of organic laying hens. Since this was an epidemiological study, further experimental studies are needed to investigate the causal relationships

Possible risk factors for keel bone damage in organic laying hens

Keel bone damage (KBD) in laying hens is an important welfare problem in both conventional and organic egg production systems. We aimed to identify possible risk factors for KBD in organic hens by analysing cross-sectional data of 107 flocks assessed in eight European countries. Due to partly missing data, the final multiple regression model was based on data from 50 flocks. Keel bone damage included fractures and/or deviations, and was recorded, alongside with other animal based measures, by palpation and visual inspection of at least 50 randomly collected hens per flock between 52 and 73 weeks of age. Management and housing data were obtained by interviews, inspection and by feed analysis. Keel bone damage flock prevalences ranged from 3% to 88%. Compiled on the basis of literature and practical experience, 26 potential associative factors of KBD went into an univariable selection by Spearman correlation analysis or Mann–Whitney U test (with P<0.1 level). The resulting nine factors were presented to stepwise forward linear regression modelling. Aviary v. floor systems, absence of natural daylight in the hen house, a higher proportion of underweight birds, as well as a higher laying performance were found to be significantly associated with a higher percentage of hens with KBD. The final model explained 32% of the variation in KBD between farms. The moderate explanatory value of the model underlines the multifactorial nature of KBD. Based on the results increased attention should be paid to an adequate housing design and lighting that allows the birds easy orientation and safe manoeuvring in the system. Furthermore, feeding management should aim at sufficient bird live weights that fulfil breeder weight standards. In order to achieve a better understanding of the relationships between laying performance, feed management and KBD further investigations are needed