A quantitative PCR method to quantify ruminant DNA in porcine crude heparin

Heparin is a well-known glycosaminoglycan extracted from porcine intestines. Increased vigilance for transmissible spongiform encephalopathy in animal-derived pharmaceuticals requires methods to prevent the introduction of heparin from ruminants into the supply chain. The sensitivity, specificity, and precision of the quantitative polymerase chain reaction (PCR) make it a superior analytical platform for screening heparin raw material for bovine-, ovine-, and caprine-derived material. A quantitative PCR probe and primer set homologous to the ruminant Bov-A2 short interspersed nuclear element (SINE) locus (Mendoza-Romero et al. J. Food Prot. 67:550–554, 2004) demonstrated nearly equivalent affinities for bovine, ovine, and caprine DNA targets, while exhibiting no cross-reactivity with porcine DNA in the quantitative PCR method. A second PCR primer and probe set, specific for the porcine PRE1 SINE sequence, was also developed to quantify the background porcine DNA level. DNA extraction and purification was not necessary for analysis of the raw heparin samples, although digestion of the sample with heparinase was employed. The method exhibits a quantitation range of 0.3–3,000 ppm ruminant DNA in heparin. Validation parameters of the method included accuracy, repeatability, precision, specificity, range, quantitation limit, and linearity

Authentication of dairy products by immunochemical methods: a review

International audienceAntibody-based techniques for the assessment of authenticity of dairy products are reviewed in this paper. Because of the inherent complexity of the protein and peptide fractions from milk and even more so from cheese, the use of immunoreagents which are more selective than polyclonal antibodies is usually required for the assaying dairy authenticity by immunochemical methods. Significant advances in this area have been achieved over the last decade thanks to advances in the antipeptide antibody technology, based on the use of properly designed peptides which mimick specified protein substructures as model antigens. Tailor-made antibodies have been developped either for the detection of single protein components or for recognizing protein adducts created by the technological processes employed. Different reagent configurations and immunoassay formats have been devised for a number of analytical applications relevant to the quality control of dairy products, ranging from the monitoring of molecular markers to the tracing of technological processes applied to milk for cheese-making

Proteinograma do soro lácteo de ovelhas da raça Santa Inês em diferentes fases de lactação

This study aimed to evaluate the influence of lactation phases on the proteinogram of whey protein in Santa Inês ewes. Ewes were accompanied in a semi-intensive system using the same sanitary and nutritional management evaluated at 15, 30, 60 and 90 days postpartum (end of weaning and lactation). Clinical examination of the mammary gland was carried out through and bacteriological culture. The screening of the material resulted in 44 milk samples of healthy glands concurrent negative by CMT and bacteriological culture exam. For obtaining the whey protein renin solution was used. The whey was fractionated into aliquots and kept in the -80C freezer to later separation of protein fractions. For determination of total protein of whey protein was employed the biuret, observing the linearity of the test. Separation of protein fractions was performed, using polyacrylamide gel containing sodium dodecyl sulfate (SDS-PAGE). Eigth protein were observed including lactoferrin, serum albumin, IgA, IgG (heavy chain IgG (IgG CP), light chain IgG (IgG CL), ß-lactoglobulin, a-lactalbumin and proteins identified as PM 15000 and PM 29000. No significant difference was observed at different stages of lactation in the following protein: IgA (P>0.3895), lactoferrin (P>0.1611), PM 29000 (P>0.4879), α-lactalbumin (P>0.0799) and PM15000 (P>0.4494). In total protein (P<0.0022), albumin protein (P<0.0377) and IgG (P<0.0354) it was observed a significant variation in the first moments of observations, in the ß-lactoglobulin protein (P<0.0005) there was significant variation with reduction of 15 to 30 days postpartum with progressive elevation until the last stage of lactation (90 days postpartum). The SDS-PAGE technique allowed the quantification of eigth whey proteins in health ewes. The protein fractions identified reflect the profile of whey to ovine species, with influence of stages of lactation in albumin, IgG and ß-lactoglobulin.Universidade Federal Rural de Pernambuco UFRPE, Av. Bom Pastor s/n. Caixa Postal 152, Boa Vista, Garanhuns, PE 55292-270UFRPE Av. Dom Manoel de Medeiros s/n, Dois Irmãos, Recife, PE 52171-030Campus Garanhuns Universidade Federal Rural de Pernambuco, Avenida Bom Pastor s/n Caixa Postal 152 Boa Vista, Garanhuns PE 55292-270Departamento de Clínica e Cirurgia Veterinária Universidade Estadual Paulista (Unesp), Campus Jaboticabal Via de acesso Prof. Paulo Donato Castellane s/n, Jaboticabal, SP 14884-900Departamento de Medicina Veterinária Universidade Federal Rural de Pernambuco Avenida Dom Manoel de Medeiros s/n, Caixa Postal 152, Dois Irmãos,RecifeDepartamento de Clínica e Cirurgia Veterinária Universidade Estadual Paulista (Unesp), Campus Jaboticabal Via de acesso Prof. Paulo Donato Castellane s/n, Jaboticabal, SP 14884-90

Brucellosis as an Emerging Threat in Developing Economies:Lessons from Nigeria

Nigeria is the most populous country in Africa, has a large proportion of the world's poor livestock keepers, and is a hotspot for neglected zoonoses. A review of the 127 accessible publications on brucellosis in Nigeria reveals only scant and fragmented evidence on its spatial and temporal distribution in different epidemiological contexts. The few bacteriological studies conducted demonstrate the existence of Brucella abortus in cattle and sheep, but evidence for B. melitensis in small ruminants is dated and unclear. The bulk of the evidence consists of seroprevalence studies, but test standardization and validation are not always adequately described, and misinterpretations exist with regard to sensitivity and/or specificity and ability to identify the infecting Brucella species. Despite this, early studies suggest that although brucellosis was endemic in extensive nomadic systems, seroprevalence was low, and brucellosis was not perceived as a real burden; recent studies, however, may reflect a changing trend. Concerning human brucellosis, no studies have identified the Brucella species and most reports provide only serological evidence of contact with Brucella in the classical risk groups; some suggest brucellosis misdiagnoses as malaria or other febrile conditions. The investigation of a severe outbreak that occurred in the late 1970s describes the emergence of animal and human disease caused by the settling of previously nomadic populations during the Sahelian drought. There appears to be an increasing risk of re-emergence of brucellosis in sub-Saharan Africa, as a result of the co-existence of pastoralist movements and the increase of intensive management resulting from growing urbanization and food demand. Highly contagious zoonoses like brucellosis pose a threat with far-reaching social and political consequences

HEAT DENATURATION OF WHEY PROTEINS COMPARATIVE STUDIES WITH PHYSICAL AND IMMUNOLOGICAL METHODS

International audienc