Using electronic identification (eid) and molecular markers (dna) for improving the traceability and meat.

Experimental results allow us to build up a logistic model for the prediction of bolus retention rate in the forestomachs of ruminants. Bolus retention rate was predicted with a standard error of the mean of approximately 1% (R2 = 0.989) in cattle and sheep. Bolus retention rate in buffaloes was also satisfactorily predicted by the model, but no definitive conclusions were obtained for goats. New ruminal boluses for the identification of cattle, buffaloes, sheep and goats, were developed aiming to obtain an annual retention rate >98% according to ICAR (2005) recommendations. The dimensions (weight; length × outside diameter; and, specific gravity) of the final electronic ruminal bolus prototypes produced were: 1) Optimised bolus for cattle (all ages), buffaloes (all ages) and goats (adults): 73g; 77 × 18mm; and, >3; and, 2) Optimised mini-bolus for lambs (>10kg) and sheep (all ages and weights): 20g; 56 × 11mm; and, >3. These bolus prototypes overcame the main drawbacks of the standard boluses previously available. Their mid- and long-term retention rate was greater than the conventional identification devices and fulfilled the ICAR (2005) recommendation. Further research is needed for goats.

Performance of low frequency (134.2kHz) glass encapsulated transponders of different sizes, high frequency (13.56 MHz) smart-tag label transponders and equipment developed in the project for reading and transfer of identification from the animal to the carcass and meat were evaluated in laboratory trials. Special reports on the radio-frequency environment and operating conditions of the reading and recording equipment produced in the project under abattoir conditions (working and not working) were done. Operating conditions did not alter significantly the devices and reader performances.

An improved hand-held transceiver (transponder reader), able to read ISO transponders and store information, for on-farm use was produced. The transceiver has an incorporated antenna but can be connected to a stick antenna, it is powered by batteries and uses wireless communication by radio frequency to interface with personal computers and other devices. Technical description: Waterproof and shock resistant. Power supply at 13.2V and 650mA. Loop antenna incorporated. Replaceable (Flash) data memory of up to 32MByte and wireless RF data communication. User interface composed of a 49 key keyboard and a 128 × 64 pixels transflective liquid crystal display. Communication by radio frequency which allows the configuration, downloading and loading of reader information at up to 30m distance. Capable of reading ISO transponders (134.2kHz) at a reading distance of 38cm. Working temperature: -10°C to +55°C.

The developed EID+DNA traceability system was implemented in a total of 8,953 pigs intended for growing-fattening and slaughtering under different on-field EU conditions: 7,065 white pigs under intensive and indoors conditions, and 1,888 black pigs under semi-intensive and outdoors conditions. Pigs were identified with visual ear tags and with EID devices (intraperitoneally injected transponders and electronic ear tags) as early as possible before weaning. At EID, ear biopsies were also taken and stored frozen for later DNA auditing. Animal EID, administrative data, movements and slaughter data were stored in the EID+DNA web database. Readability of visual ear tags was satisfactory during on-farm growing-fattening periods, but not during slaughter. Readability of intraperitoneally injected transponders (EID) was satisfactory in white pigs (98.2-99.4%) but reading limitations (insufficient reading distance) were reported in the heavy black pigs requiring the use of improved readers. Automatic transfer of animal EID to the carcasses by using smart-tags, after adaptation of reading-recording equipment to the high throughput abattoir conditions was satisfactory. All slaughtered animals were also DNA sampled and samples stored frozen until analysis. Traceability from farm to the end of slaughtering line, audited by DNA analysis done at random in a total of 5% samples, averaged 99.5% (99.6 and 100% for white and black pigs, respectively). In conclusion, the proposed EID+DNA dual traceability system was enough effective for the EU meat industry although operational differences and limitations between countries were reported.

The developed EID+DNA traceability system was implemented in a total of 9,546 ruminants intended for fattening and slaughter under on-field EU conditions (5,838 beef cattle and 3,708 lambs). All animals were identified with official ear tags, according EU regulations, and with EID boluses as early as possible. At bolusing, ear biopsies were also taken and stored frozen for later DNA auditing. Animal EID, administrative data, movements and slaughter data were stored in the EID+DNA web database. Retention of improved EID boluses developed in the project was greater than observed for official ear tags. Automatic transfer of animal EID to the carcasses by using smart-tags was affected by abattoir throughput but, after equipment reading-recording adaptation, was satisfactory. All slaughtered animals were also DNA sampled and samples stored frozen until analysis. Traceability from farm to the end of slaughtering line, audited by DNA analysis done at random in a total of 5% samples, averaged 98.0% and 97.8% for lamb and cattle, respectively. Traceability of meat from abattoir (carcase) to retailer (meat cut) was 100%. In conclusion, the proposed EID+DNA dual traceability system was enough effective for the EU meat industry although operational differences and limitations between countries were reported.

Comparison of different sampling, preservation and analysis methodologies allowed choosing specially designed ear tag biopsiers as the most appropriate device for collecting biopsies for molecular marker (DNA) analysis. Specific sets of 8 DNA microsatellites (STR, short tandem repeat) were chosen from the internationally agreed ISAG list and tested for genetic identification of cattle, sheep and pigs. Extra sets of 4 microsatellites were also chosen as complementary markers for the three species. Chosen STR was used for auditing the traceability of cattle, sheep and pig samples during the implementation phase of the project. Specific sets of 41 and 48 single nucleotide polymorphism (SNP) were also identified for cattle and pigs for genetic identification of cattle and pigs, respectively. Chosen SNP was used for auditing the traceability of pig samples during the implementation phase of the project. Exclusion probability with both STR and SNP methodologies was >99.9%.

Intraperitoneal injection of 32mm glass encapsulated transponders was the procedure agreed in the project for pig identification. Readability results were > 98% during the farm and the slaughterhouse periods. The injection procedure was adequate for piglets between 3 and 30d of age, but it can also be done in older pigs with an adapted restraining. Short and simple training of operators is required for farm implementation. Injection is recommended on the left side of the pig, between ventral line (Linnea alba) and mammary blood vessels to avoid bleeding, at approximately 1cm from the ventral line and 2(-8)cm caudally to the navel (according the animal size and age), in a perpendicular direction towards the abdominal cavity. Only local disinfection is required. No negative effects of the intraperitoneal injection on animal performance are expected. Very low risk of placing transponders in the carcass was shown but improvement of the natural attachment to the abdominal viscera is recommended for an easier recovery after slaughtering.

An automatic system to be used for transferring animal electronic identification (EID) to the carcasses was developed based on the use of read and write high frequency (HF, 13.56MHz) inlay transponders included in flexible labels ("smart-tags"). The system allowed the automatic transfer of information from low frequency (LF, 134.2 kHz) electronic devices used for animal identification (electronic bolus, ear tag, injectable) to the HF smart-tag labels placed on the carcass or meat cuts. Smart-tags are price competitive and no-collision (able to be read in groups) devices. The process followed in the slaughtering line is: 1) One (or two) smart-tag is placed on the shank of the slaughtered animal before evisceration; 2) Hook from which the animal body is hanging activates a LF reader when arriving at the reading point; 3) LF transponder (animal EID) is read (inside the animal or at evisceration) and LF reader switched off; 4) EID code is transferred to a HF recording unit; 5) EID animal code is recorded on the HF smart-tag and the reader is switched off; 6) Optional information is recorded in HF smart-tag before carcass releasing.

An automatic retriever of bolus transponders was developed based on an invented process using the principles of reading and immediate physical separation of the transponder. The process to recover the identification boluses located inside ruminant forestomachs comprises the steps of: 1) slaughter the animal; 2) evisceration; 3) cutting for emptying the cavity of the forestomachs where the bolus is located (reticulo-rumen) and removing its whole reticulo-rumen content (digesta containing the bolus); 4) displacement and elevation of the whole content; 5) dropping of the whole digesta content in a vertical pipe equipped with a circular antenna for detecting the transponder located inside of the bolus; 6) transponder detection; 7) activation of a pneumatic flap for instantaneous interception of the dropping bolus; and, 8) collection and storing of the retrieved boluses. Automatic recovery was found ineffective for intraperitoneally injected transponders.

Software models on computer spreadsheets for estimating animal identification costs using conventional and electronic systems for ruminants (sheep and goat, cattle) and pigs were developed in the project. The models were shared with public and private organizations on demand and were used for studying cost-benefit analysis of meat traceability under European conditions. Results obtained with the model indicate the advantage of using mixed identification systems (conventional and electronic) under the current scenario. Cost was dramatically affected by animal specie, farm size and prices of reading equipment, ranging between: sheep and goat (2.48-4.64), pigs (3.33-5.21) and cattle (14.1-18.24). Case studies analysed in detail include the implementation of Regulation 21/2004 for sheep and goat in Spain (already published) and a comparative study in the European Union (developed by the JRC for the European Commission). Meat traceability cost and cost-benefit analysis were also performed by simulation analysis for beef and pork in different European scenarios.

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