EFSA scientific risk assessment on animal health and welfare aspects of avian influenza (EFSA-Q-2004-075).

Outbreaks of highly pathogenic avian influenza (HPAI) (2000-2003) resulted in 50 million EU birds culled or dead. The circulation of H5N1 in Asia could represent the origin of a human pandemic. Questions have been raised to combat the ongoing AI crisis. HPAI H5N1 has spilled over to resident and migratory wild bird populations which could represent a means of the virus reaching the EU, but lack of data make any forecast imprudent. Poultry holdings located close to migratory bird breeding and resting sites are considered at greater risk of exposure and methods to prevent exposure should be implemented. Legal safeguards for importation of poultry commodities currently only apply to HPAI and rely on detection of clinical signs that may not be observable during incubation period. Illegal imports represent an additional risk. Insufficient data on the effectiveness of commodity processing are available and few indications can be deducted. Biosecurity is the primary tool to prevent AI introduction and secondary spread. Massive spread was observed in densely populated poultry areas resulting in vaccination programs. Vaccination should be used to support eradication together with enhanced biosecurity and restriction measures, which shall also be implemented in case of prophylactic vaccination. Animal welfare aspects of AI include use of appropriate culling methods, correct vaccine application, and availability of trained staff. EFSA has recently set up a new scientific work group to further assess the risk of HPAI introduction and spread posed in particular by wild, migratory birds, as well as further follow-up of recent AI developments.

Residues from veterinary medicinal products, growth promoters and performance enhancers in food-producing animals: a European Union perspective.

The authors present an overview of the presence of residues from veterinary medicinal products, growth-promoting agents and performance enhancers in food-producing animals, as a result of administering these substances--legally or illegally--on farms. The current situation in the European Union (EU) is represented by an analysis of the 2004 results from the national residue monitoring plans of EU Member States. Aspects of ante-mortem and postmortem inspection are also considered, as well as the practical challenges facing veterinary inspectors attempting to uncover illegal uses and prevent public health risks. Substances which are considered illegal because their risks have not yet been assessed, such as those employed in minority species or for minor uses, are also discussed.

Retention of different sizes of electronic identification boluses in the forestomachs of sheep.

Twelve types of electronic identification ruminal boluses of different dimensions were used to obtain a model for predicting their retention in the forestomachs of sheep. Boluses (n = 1,662) were made of ceramic materials, and their dimensions varied in o.d. (9 to 21 mm), length (37 to 68 mm), volume (2.5 to 21.0 mL), and specific gravity (0.85 to 3.91). Each bolus contained a half-duplex, standardized, glass-encapsulated transponder (32 x 3.8 mm). Boluses were administered to sheep (n = 1,497) of different ages by using the appropriate balling guns, and their retention under semiintensive conditions was recorded for at least 2 yr. When a bolus was lost, the sheep was rebolused with a heavier bolus. All sheep wore 2 plastic ear tags: one for the official control of health programs and the other for farm use. To determine the anatomical limit for a bolus passing through the gastrointestinal tract, the size of the reticulo-omasal orifice was measured in 46 adult sheep (male, n = 14; female, n = 32) that died by causes not related to bolus administration during the experiment. No signs of disease or growth alteration were detected in the bolused sheep. Total ear tag losses during the experiment period were 7.5% on average. Bolus retention (5 to 100%) varied according to bolus features and age of the sheep, but it showed a plateau after 18 mo. Inadequately dimensioned boluses were regurgitated or passed through the gastrointestinal tract and were excreted with the feces. The diameter of the reticulo-omasal orifice in adult sheep differed between male and female (23.1 and 21.8 mm, respectively; P < 0.01) and was greater than the o.d. of the retained boluses. Retention rate was predicted from bolus weight and volume by a logistic regression (R2 = 0.997; P < 0.001). When retention data from the literature (59.0 to 100%) were included in the model, the adjustment was slightly lower (R2 = 0.967). As a result, the minimum bolus weight estimated to reach a 99.5% retention rate in sheep varied between 16 and 45 g when volume varied between 3 and 22 mL, for boluses with a specific gravity between 2.0 and 5.2. In conclusion, bolus retention rate in sheep varied dramatically according to their features. For safe and efficient retention of electronic identification boluses in sheep, boluses of small volume and diameter (e.g., < 15 mm) with specific gravity and weight greater than 3.0 and 20 g, respectively, are recommended.

The use of passive injectable transponders in fattening lambs from birth to slaughter: effects of injection position, age, and breed.

A total of 1,159 Tiris half-duplex passive injectable transponders (PIT) of 32-mm length were used to study the electronic identification of 618 fattening lambs of two breeds used for different production purposes (Ripollesa, meat breed, n = 271, and Manchega, dairy breed, n = 347). The lambs were s.c. injected in the armpit and the retro-auricular positions at 2, 15, and 30 d of age. All lambs were also tagged with a small plastic ear tag after birth. A group of 76 lambs were injected only in the right armpit and were kept for breeding. The PIT losses, breakages, and electronic failures were evaluated at weekly weight recordings throughout the fattening period using two types of hand-held transceivers. Fattened lambs were harvested in a commercial abattoir between 3 and 4 mo of age when they reached market weight (11 to 12 kg hot carcass weight). The total number of PIT that fell or broke in the slaughtering line, the location method, and the recovery time were recorded. On the farm PIT losses were not affected (P > 0.05) by age at injection, injection position, or breed. Mean losses of PIT and ear tags during the same period were 5% and 6.3%, respectively (P > 0.05). No PIT breakages or failures were observed during the fattening period. Mean recovery of PIT in the abattoir (85.6%) was affected (P < 0.05) by breed and injection position. Losses of PIT in the abattoir were greater (P < 0.05) in the Ripollesa breed (18.4%) than in Manchega (10.0%), and for both breeds losses were greater (P < 0.05) in the retro-auricular than in the armpit positions (18.6 vs 10.8%, respectively). The percentage of PIT broken during slaughtering was low (0.3%). The mean recovery times (18 +/- 2 s) were not affected (P > 0.05) by breed, injection position, or age, thus allowing a harvesting speed of 200 lambs/h on average. In conclusion, the injection of 32-mm PIT into the armpit or the retro-auricular region is not recommended as a practice for the electronic identification of fattening lambs, even though they perform similarly to small plastic ear tags. This is partly a consequence of the PIT losses observed on the farm but mainly because of the difficulties with recovering the PIT in the abattoir. More research will determine whether the use of smaller transponders or injection in other positions could improve their performance in fattening lambs.

IDEA: a large-scale project on electronic identification of livestock.

The aim of the IDEA (Identification électronique des animaux) project is to collect information on the feasibility of the introduction into the European Union (EU) of an animal electronic identification system, as referred to in Directive 92/102 and Regulation 1760/2000. The project will run for a period of four years (1998-2001) and will include one million animals in six countries (France, Germany, Italy, The Netherlands, Portugal and Spain). The Joint Research Centre, as technical co-ordinator of the project, provides technical support in terms of testing and certification of electronic identification devices, establishment of the central database, transmission and recording of data and evaluation of results. Identification has been undertaken in cattle, sheep, goats and buffalo using three types of electronic tags (ruminal bolus, ear tag and injectable transponder). The performance of these tags is checked at defined intervals until recovery in the slaughterhouse. The evaluation of the results in terms of the performance of the device and the necessary organisational support structures will lead to recommendations for a system to trace animals from birth to slaughterhouse, including the appropriate technology to be applied in any generalised system for the livestock sector in the EU.

Effects of injection position and transponder size on the performances of passive injectable transponders used for the electronic identification of cattle.

A total of 686 Tiris half-duplex passive injectable transponders (PIT) of two sizes (23 and 32 mm) were randomly injected s.c. in three positions, armpit, ear scutulum, and upper lip, in 343 fattening calves (1 to 3 mo old). Injections were performed by two trained and two untrained operators. Losses and breakages on the farm were recorded at wk 1, 3, 7, 11, and 15 in restrained animals using two types of hand-held transceivers with a stick antenna. Dynamic reading efficiency (DRE) in animals running through a raceway was also evaluated at wk 1 and 3 and monthly until slaughter, using a stationary transceiver working at 137 dB x microV x m(-1) at 3 m. The total number of PIT that fell or broke in the slaughtering line, the location method, and the recovery time were also recorded. Results on the farm showed low breakages on average (0.4%) and differences (P < 0.05) in losses according to position (armpit, 1.7%; ear, 5.2%; and lip, 14.0%). An interaction (P < 0.05) between position x size was observed, and losses were greatest using a 32-mm PIT in the lip. The DRE was affected (P < 0.05) by PIT position and size, and values were greater for the 32-mm PIT in all positions (armpit: 99.9 +/- 0.1 vs 95.8 +/- 4.9%; ear: 93.8 +/- 2.2 vs 81.9 +/- 4.6%; lip: 66.8 +/- 4.9 vs 53.4 +/- 4.7%, respectively, for 32 vs 23 mm). Recovery of PIT in the abattoir was on average 96.7, 96.7, and 99.2% for armpit, ear, and lip, respectively (P > 0.05). Most of the PIT injected in the armpit were recovered by sight or palpation, but 31.9% were recovered after cutting the muscles around the area and 10.7% were recovered on the internal side of the hide, which jeopardized carcass identification. Recovery of PIT injected in the ear was 23.4% in the hide and 76.6% in the auricular muscles of the head. The easiest recovery was in the lip, 8.9% of PIT were located in the hide and 91.1% in the head. Recovery time was affected (P < 0.05) by position: the quickest was lip (27 +/- 2 s), followed by ear (52 +/- 5 s) and armpit (78 +/- 7 s). In conclusion, taking into account retention and reading performances, injection of a 32-mm PIT into the armpit showed the best results on the farm, but a careful and longer recovery was needed in the abattoir. Improvement of recovery methodology and time would be necessary in order to recommend injection of PIT in the armpit instead of in the ear for cattle tracking or monitoring.

Comparative analysis of morphological and behavioral characters in the domestic dog and their importance in the reconstruction of phylogenetic relationships in canids

Relationships among 25 dog breeds, classified a priori by their respective ancestral trunks, were studied using data from 29 morphological and 13 behavioral characteristics. Although a certain correlation was found between both types of traits (r = 0.13; P < 0.05), this relationship was not manifested, regarding the level of racial classification, in the obtained dendrograms. The relationships between breeds obtained from morphological data were more congruent than those obtained from behavioral data when compared with phylogenies from other sources of information (mainly electrophoretic analysis). This indicates that the morphological characters could give more and better complementary information than the behavioral ones in the reconstruction of the phylogenetic relationships of canids. The mean character difference (MCD), used as a measure of taxonomic resemblance between breeds, had a value of 0.53 (+ or - 0.12 STD), and was of a magnitude very similar to that obtained in other domestic animal species (cattle, horse, sheep and goats), indicating that a similar degree of morphological differences between breeds of these species exists.