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R Osta

Publications and source records attributed to R Osta.

17 recordsLinked to original sources
PubMed2001

Random amplified polymorphic DNA fingerprints for identification of species in poultry pâté.

Because some fraudulent or unintentional mislabeling occurs that can be undetected, resulting in lower quality pâté, and because some population groups, for philosophical or religious reasons, do not wish to eat meat from certain species, a new procedure was developed and evaluated to detect pâté species composition by randomly amplified polymorphic DNA (RAPD). The RAPD method was used to generate fingerprint patterns for pork, chicken, duck, turkey, and goose meats. Ten DNA samples from pork, chicken, turkey, and duck meats were tested to confirm the effectiveness and specificity. Specific results for each species were obtained by the RAPD method. Sensitivity of the method was studied by DNA dilution in each species, detecting as little as 250 pg of DNA. Isolations of DNA from 30 pâtés (tinned and untinned) were carried out, and an optimal DNA was obtained for using as template DNA in polymerase chain reaction (PCR). The RAPD-PCR pattern was useful to identify species composition of pork, duck, duck-pork, goose, and poultry pâtés. This study demonstrates the usefulness of RAPD fingerprinting to distinguish between species in pâtés.

Animals↗
PubMed2001

Technical note: A quick and more sensitive method to identify pork in processed and unprocessed food by PCR amplification of a new specific DNA fragment.

We developed and evaluated a PCR procedure to detect pork in heated and unheated meat, sausages, canned food, cured products, and pâtés using a faster, more specific, and more sensitive method than others previously described. Isolation of a new DNA-specific porcine repetitive element was performed by nonspecific PCR amplification. After analyzing this repetitive sequence, a pair of primers were synthesized. To confirm the effectiveness and specificity of this fragment, 55 pig blood DNA samples (from differents breeds) were tested and positive results were obtained. With 200 samples tested from other species, the specific pork amplification was not detected. Using this method, we can partially quantify degree of contamination, depending on the PCR amplification cycles, detecting up to 0.005% pork in beef and 1% pork in duck pâté using 30 and 20 PCR amplification cycles, respectively. The amount of porcine DNA detected in cattle DNA was 1.25 and 250 pg when using 30 and 20 amplification cycles, respectively. Pork has been identified in both heated and unheated meat products, sausages, canned food, hamburgers, and pâtés. In conclusion, specific PCR amplification of a repetitive DNA element seems to be a powerful technique for the identification of pork in processed and unprocessed food, because of its simplicity, specificity, and sensitivity (with 30 amplification cycles we can detect 0.005% pork). Furthermore, it is a very fast method, because 1% pork contamination can be detected with 20 PCR cycles. The procedure is also much cheaper than other methods based on RFLP-PCR, immunodiffusion, or other techniques that need expensive equipment.

Animals↗
PubMed1997

Construction of hybrid proteins that migrate retrogradely and transynaptically into the central nervous system.

The nontoxic proteolytic C fragment of tetanus toxin (TTC peptide) has the same ability to bind nerve cells and be retrogradely transported through a synapse as the native toxin. We have investigated its potential use as an in vivo neurotropic carrier. In this work we show that a hybrid protein encoded by the lacZ-TTC gene fusion retains the biological functions of both proteins in vivo-i.e. , retrograde transynaptic transport of the TTC fragment and beta-galactosidase enzymatic activity. After intramuscular injection, enzymatic activity could be detected in motoneurons and connected neurons of the brainstem areas. This strategy could be used to deliver a biological activity to neurons from the periphery to the central nervous system. Such a hybrid protein could also be used to map synaptic connections between neural cells.

Animals↗
PubMed1994

Effect of genetic factors on the criteria of stress in fighting bulls.

The effect of 40 genetic markers (blood groups and biochemical polymorphisms) on 5 haematological parameters (haematocrit, haemoglobin concentration, red blood cells count, white blood cells count and differential leucocyte count) was studied in 179 fighting bulls to investigate whether genetic background was related to stress endurance. Analysis of data was carried out by Harvey's methods (1977). Environmental factors (season, management before the bullfight, "encierro" and suffered punishment), body constitution and pedigree were also included in the analysis. The A, B and S system of cattle blood groups, erythrocyte carbonic anhydrase (Ca) and transferrin (Tf) genotypes showed a significant effect on all studied parameters. Our results show that fighting bulls with the H antigen and those without A, G2 and G3 antigens had lower haematocrit and haemoglobin concentrations than the average population, whereas the fighting bulls with CaS/CaS and TfA/TfE genotypes showed a higher reversal of the leukocyte differential count than the average population. These results may suggest a better adaptation to resistance to stress in animals displaying H antigens and CaS/CaS, TfA/TfE genotypes and in those without A, G2 and G3 antigens.

Aggression↗
PubMed1993

[Relationship between genetic markers and serum enzymatic activity in fighting bulls].

The relationships between 41 genetic markers (blood groups and biochemical polymorphisms), 3 environmental factors (season, management before the Lidia ("encierro"), punishment suffered), body constitution, and pedigree on the one hand, and the activity of muscular enzymes in serum, creatine kinase (CK), lactate dehydrogenase (LDH), aspartate transaminase (AST)) on the other, were analyzed in 179 fighting bulls. The C system of cattle blood groups and the "encierro" were significantly related to the activity of the muscular enzymes of the studied animals. The fighting bulls with the W1 and C1 antigens had a higher CK and LDH activity respectively, whereas the fighting bulls with the X1 antigen as well as those that participate in the "encierro" had a lower AST activity. This results could suggest a lesser degree of muscular injury during the Lidia in animals with X1 antigen, in those that participate in the "encierro", and in those without W1 and C1 antigens.

Animal Husbandry↗
PubMed1992

Characterization of five new bovine dinucleotide repeats.

Five new bovine (TG)n microsatellite sequences were characterized. During the screening procedure, one-third of the clones had essentially the same flanking sequences. A fast technique was devised to eliminate these clones.

Alleles↗