// Determination using Real-Time PCR
// Identification, Differentiation and Quantification of Animal Species
Animal species analysis
The identification of animal species in food is becoming increasingly important for reasons of quality assurance, health, and ethnic aspects. This analysis serves primarily to ensure that food products are non-hazardous to health and correctly labelled. For example, fast and reliable processes can reliably detect the admixture of inferior products and the associated adulteration. This is not only about product quality but also the safety of the end consumer.
The exclusion of meat or animal products is also absolutely necessary for certain forms of nutrition such as vegetarianism or veganism. This requires highly sensitive analytical methods and is an essential part of quality assurance. Religious diets in which certain animal species (e.g. pork and goat) are not allowed to be eaten are also becoming increasingly important and require sensitive detection methods. The restrictions on dietary habits apply not only to meat products but also to products containing porcine gelatine, for example.
The monitoring of the authenticity of fish also plays an ever-increasing role. The demand for certain fish species is growing steadily. However, the stock of fish species continues to decline because of overfishing. In some cases, fish species with limited availability are replaced by cheaper species. Such product adulterations and obvious deceptions can also be detected by fish species differentiation.
The variety of sample matrices and process steps always influence the choice of suitable detection methods. The CONGEN ServiceLab is a specialist in the field of animal species analytics using real-time PCR. Specific and sensitive methods enable rapid analysis with reproducible results.
General Detection of Animals
- Terrestrial vertebrates (without amphibians)
- Beef (Bos taurus)
- Bison (Bison bison, Bison bonasus)
- Cat (Felis catus)
- Camel / Dromedary / Bactrian Camel (Camelus species)
- Dog (Canis familais)
- Donkey (Equus asinus)
- Fallow Deer (Dama dama)
- Goat (Capra hircus)
- Hare (Lepus europaeus)
- Horse (Equus caballus)
- Kangaroo (Marcropodidae)
- Mouse (Mus musculus)
- Pork (Sus scrofa)
- Rabbit (Lepus cuniculus)
- Rat (Rattus norvegicus)
- Red Deer (Cervus elaphus)
- Reindeer (Rangifer tarandus)
- Roe Deer (Capreolus capreolus)
- Ruminants (beef, sheep, goat)
- Sheep (Ovis aries)
- Springbok (Antidorcas marsupialis)
- Water buffalo (Bubalus arnee)
- Chicken (Gallus gallus)
- Goose (Anser anser)
- Ostrich (Sruthio camelus)
- Poultry (goose, chicken, turkey, duck, ostrich, quail)
- Turkey (Meleagris gallopavo)
- Quail (Coturnix coturnix)
- Differentiation of fish species with sequencing
- Alaska pollock (Gadus chalcogramma)
- Atlantic cod (Gadus morhua)
- Atlantic halibut (Hippoglossus hippoglossus)
- Greenland halibut differentiation (Reinhardtius hippoglossoides)
- Atlantic salmon (Salmo salar)
- Chinook salmon (Oncorhynchus tshawytscha)
- European hake (Merluccius merluccius)
- Haddock (Melanogrammus aeglefinus)
- Humpback salmon (Oncorhynchus gorbuscha)
- Pacific cod (Gadus macrocephalus)
- Pollock / Saithe (Pollachius virens)
- Rainbow trout (Oncorhynchus mykiss)
- Skipjack tuna (Katsuwonus pelamis)
- Sockeye (Oncorhynchus nerka)
- Trout (Salmo trutta)
- Whiting (Merlangius merlangus)
Additional Animal Species
- Crustacean differentiation by sequencing
- Scallop species differentiation by sequencing
- Squid species differentiation by sequencing
The analyses comprises the following steps:
Homogenization and DNA extraction
You send a representative part of the sample material to our service laboratory. The sample is homogenized, and the DNA is extracted in duplicate. Of course, appropriate controls will be carried out:
- The negative extraction control as an indication of buffer contamination or carry over during extraction.
- The positive extraction control (as proof of the functionality of the method used) is carried out in the form of a lot-dependent process control.
The extracted sample DNA can be analysed for up to six parameters using real-time PCR. In qualitative procedures, negative, inhibition, and positive controls are routinely used. If the controls show the expected results, you will receive a test report with the corresponding results and the system-specific detection limit. Please note that the determination is not matrix-specific.
Qualitative DNA Detection
In contrast to allergens, the detection of animal components or animal species in a sample is generally not designed for the determination of contaminants. The animal detections serve to identify animal species in order to prevent product adulteration. The detection limit is therefore designed for the determination of ingredients in the % range. One exception is the sensitive detections for beef and pork, which each have a much lower detection limit. For example, sensitive detection on pork is interesting for the autentication of halal products.
Relative quantitative DNA detection
A reliable and correct quantification is only possible for meat samples with a muscle meat content ≥ 95 % because samples with an offal content of > 5% (e.g. liverwurst) have a higher DNA content and thus falsify the overall result.
The quantitative method we offer is based on relative quantification. This means that the specific animal species DNA (e.g. beef) is determined relative to the total animal DNA content in meat products. Two real-time PCR systems are used: a detection system and a reference system. The copy number is determined using a standard series. The ratio of detection genes to animal reference genes is determined from the calculated copy numbers for the tested sample and the positive control. The sample matrix and the degree of processing influence the quantitative result as well as the detection and determination limit. Because of the relative calculation, the determination limit is sample-specific.
Among other things, fish fillets can be identified by sequencing. However, this detection is only suitable for whole fish fillets. Furthermore, the CONGEN ServiceLab offers a differentiation by sequencing for scallops and crustaceans. A sequencing of mixed samples is not possible.
PCR is carried out on the sample for analysis, whereby a specific, highly conserved gene section is specifically amplified. This PCR product is then sequenced. By comparing the sequence with a database, it is possible to determine the species.