Although the prevalence of lead poisoning in southern Africa's Gyps vultures is now well-established, its finer physiological effects on these endangered species remain poorly characterised. We evaluated the sub-lethal impact of acute lead exposure on Cape and White-backed Vulture chicks from two breeding colonies in South Africa, by analysing its possible effects on key blood biochemistry parameters, immune function, packed cell volume and δ-aminolevulinic acid dehydratase (δ-ALAD) activity. All 37 White-backed Vulture nestlings sampled displayed elevated lead levels (>10 μg/dL), and seven had blood [Pb] >100 μg/dL.
View Article and Find Full Text PDFElevated lead levels in scavenging raptors can originate from a variety of environmental and anthropogenic sources, including soil, water, mining activities and legacy lead from leaded fuel, but has mostly been attributed to fragments of lead-based ammunition embedded in the tissues of carcasses. To identify the origins of lead in the tissues of white-backed vulture (Gyps africanus) chicks at Dronfield Nature Reserve, South Africa, we used MC-ICP-MS to compare the isotopic composition of lead in blood samples to those of soil in the chicks' immediate environment, different mining activities in South Africa and lead ammunition commonly used in hunting and game management practices. The isotopic ratios in vulture blood samples ranged widely (Pb/Pb: 0.
View Article and Find Full Text PDFAfrican wildlife face challenges from many stressors including current and emerging contaminants, habitat and resource loss, poaching, intentional and unintentional poisoning, and climate-related environmental change. The plight of African vultures exemplifies these challenges due to environmental contaminants and other stressors acting on individuals and populations that are already threatened or endangered. Many of these threats emanate from increasing human population size and settlement density, habitat loss from changing land use for agriculture, residential areas, and industry, and climate-related changes in resource availability.
View Article and Find Full Text PDFPoisoning, including secondary lead poisoning, is cited as the single most important cause of vulture mortalities in Africa. To evaluate the prevalence of lead poisoning among South Africa's Gyps vultures compared to other, non-scavenging birds, we obtained blood and bone samples from Cape (Gyps coprotheres) and White-backed (G. africanus) vultures.
View Article and Find Full Text PDFInt J Biochem
February 1992
1. Peptide T and four other aminoacyl derivatives of this octapeptide were synthesized on solid phase support using the Boc and Fmoc procedures. 2.
View Article and Find Full Text PDF1. Aflatoxin B1 serves as an activator for protein kinase C (PKC). 2.
View Article and Find Full Text PDFFormalin-fixed samples (n = 75) of commercial boerewors (traditional farm style sausage) were examined for total nitrogen (N) and hydroxyproline (Hypro) N to assess their collagen content. Hypo N/total N x 10(3) (unaffected by residual fat) varied from 8.23 to 16.
View Article and Find Full Text PDFThe free fatty acid (FFA) content of milk from the paired normal (N) and septic (Staphylococcus aureus or S. agalactiae) subclinically mastitic (SSM) quarters of dairy cows was determined by thin layer chromatography. Within-cow comparisons showed the FFA content of milk from the SSM quarters to be consistently significantly higher than that of the opposing N quarters: initially and after warm agitation and both rapid and slow cooling prior to storage at 4 degrees C for 48 h.
View Article and Find Full Text PDFThe effect of different pre-slaughter rest periods at the abattoir before slaughter on the blood biochemical parameters and meat pH of a number of cattle were studied on 2 occasions, once in summer and once in winter. In the first trial, 42 out of a consignment of 50 and in the second trial, 45 out of a consignment of 54 feedlot-finished oxen were randomly selected and divided into 3 groups each. One group was slaughtered on arrival at the abattoir, a second group 3 h after arrival and the third group was rested in the lairage prior to slaughter the following day.
View Article and Find Full Text PDFFollowing concern about the recent publication indicating the possible ability of Brucella abortus to survive commercial pasteurisation of naturally contaminated milk, such milk was subjected to biological (BT), serological and bacteriological tests. The raw milk was Brucella Milk Ring Test positive and biotype I was isolated from 4/5 BT guinea pigs, the one tested being seropositive to the Rose Bengal Test, and with serum agglutination and complement fixation titres of 160 and 36 international units respectively. After batch (63 degrees C/30 min) and high temperature, short time (72 degrees C/15 sec) pasteurisation, all 10 BT guinea pigs were bacteriologically and serologically negative, indicating that officially approved methods of commercial pasteurisation rendered naturally Brucella-contaminated raw milk safe for consumption.
View Article and Find Full Text PDFThe investigation was performed on 3 cows, sampled repeatedly before and during the initial 48 h of artificially induced, acute, clinical mastitis. The results of the investigation both augment and support those of earlier work on the levels and significant correlations of glucose, serum albumin and somatic cells in normal and abnormal secretions monitored before and after the usual milking of healthy lactating cows had been suspended. During acute mastitis, udder secretions from artificially infected quarters showed highly significant escalations of somatic cell counts which coincided with equally significant increases of a high and intermediate level of serum albumin values in both the infected and non-infected quarters.
View Article and Find Full Text PDFThe serological and biochemical characteristics of 100 strains of Streptococcus agalactiae isolated from quarter mild of dairy cows and of 107 strains cultured from various sites of human patients, were determined and compared. All the isolates were CAMP-phenomenon and Na-hippurate positive, aesulin negative, fell into Lancefield's Group B and could be placed into one of the 6 recognised serotypes. No human isolates fell into type R but for the rest all the other types were represented in the series of bovine and human cultures.
View Article and Find Full Text PDFIntrapapillary deposition of 5-30 CFU of 6 separate human strains of Group B streptococci into 7 lactating quarters of 6 cows resulted in clinical mastitis in all. Identical streptococci were subsequently recovered from 6 of the affected quarters. Details of milk somatic cell counts, bacterial isolations and clinical findings are tabulated.
View Article and Find Full Text PDFThe results of parallel examination by two methods of 223 consignment samples of carcase meal were compared. Selective pre-enrichment of 5 g of sample prior to plating on to a solid media disclosed that 2,7% of consignments were contaminated with Salmonella. Non-selective pre-enrichment of 100 g followed by selective enrichment prior to plating food 21,5% of the consignment to contain Salmonella.
View Article and Find Full Text PDFOn the single examination of 6804 quarter milk samples during a routine mastitis survey in 17 herds it was found that whereas 12,4% of quarters were diagnosed as subclinically mastitic when using the IDF standard set of diagnostic criteria, only 2,4% were positive when applying the additional criterium of a positive test for bovine serum albumin. The remaining 10% of quarters were then classified as being affected with septic inflammation of the ducts. The ratio of true subclinical septic mastitis to duct and test canal infections is recorded and the implications of the findings are briefly discussed.
View Article and Find Full Text PDFJ S Afr Vet Assoc
December 1976
A series of 152 quarters affected with subclinical staphylococcal and streptococcal mastitis was treated at random by intramammary infusion with one of 4 formulations containing inert solvent, specially prepared immunoglobulin (Ig) and antibiotics (penicillin G and streptomycin) in various combinations. The effect of treatment was measured by assessing the conversion of mastitic quarters to a normal or mastitis-negative state over a post-treatment period of 28 days. Considering the solvent as a placebo, solvent plus Ig had no significantly better effect than solvent only; solvent plus antibiotics gave results that were highly significant after 14 days even though about a third of the strains of S.
View Article and Find Full Text PDFOnderstepoort J Vet Res
March 1976
Cysticerci of Taenia solium were exposed to gamma radiation in doses varying from 20-140 krad. Radiation had an adverse effect on the ability of the cysticerci to evaginate in vitro after a time lag of 9 days. This effect was most marked at doses of 100 krad and higher, thus no cysticerci exposed to 140, 120 and 100 krad evaginated after 12, 18 and 21 days, respectively.
View Article and Find Full Text PDFJ S Afr Vet Assoc
September 1975
Using aqueous urea solution extracts of heated ostrich muscle as antigen for the production of precipitating rabbit antiostrich sera, it was possible to specifically identify raw, heated (70-95 degrees C) and air dried-salted ostrich meat by means of gel immunodiffusion tests. The sera did not react with chicken, turkey or horse meat or with beef in any form. The soluble proteins extracted from ostrich meat heated to temperatures of 70 degrees C for 30 minutes appear to constitute at least two closely related antigenic determinants of which only one is thermostable at temperatures above 70 degrees C).
View Article and Find Full Text PDF