PubMed · 9599167
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
F van Rossem. 1997-11-15. [Americans study Internal Quality Control].. https://pubmed.ncbi.nlm.nih.gov/9599167/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Hypodermosis is a myiasis of cattle mainly found in the Northern Hemisphere. In Italy it has been reported primarily in southern regions with a farm prevalence reaching a peak of 85%, while few data are available in the north of the country. This paper reports the results of a serological survey carried out on hypodermosis in Vicenza province (northeastern Italy). During January and February 1999, bulk milk samples were collected from 224 dairy farms and tested, using an hypodermosis ELISA kit. Epidemiological data, such as farm location, herd size, number of cows, grazing management, treatments against Hypoderma larvae, presence of imported animals, were gathered and statistically analysed in relation to the serological results. In 15 farms the presence of warbles was monitored by manual palpation and larvae collected for identification.Ninety-seven (43.3%) samples were detected as positive, whereas 12 (5.4%) and 115 (51.3%) were inconclusive and negative, respectively. Thirteen farms were positive upon parasitological examination and the larvae collected were identified as Hypoderma bovis.Seroprevalence was highly correlated with the practice of free grazing and slightly, but significantly, correlated with the number of cows on the farm. The mean antibody level of positive herds was significantly higher on farms without imported animals. On farms with warbled animals there was a high inverse correlation between antibody level and quantity of milk in the tanks and the number of lactating cows. The ELISA test on bulk milk samples has been shown, under field conditions, to be a useful, cost-effective and easy test for the diagnosis of bovine hypodermosis.
Equine protozoal myeloencephalitis (EPM) is a neurological disease of horses and ponies caused by infection of the central nervous system with the protozoan parasite Sarcocystis neurona. A herd-level analysis of a cross-sectional study of serum antibodies to S. neurona in Michigan equids was conducted, using data collected in 1997 for study that included 1121 equids from 98 Michigan horse farms. Our objective was to identify specific herd-level risk factors associated with seropositivity. We tested associations between herd seroprevalence and various farm-management practices (including feed-storage methods and wildlife control). Multivariable models were developed for three strata based on relative opossum abundance (opossum districts). Herd seroprevalence ranged from 0 to 100% (median=57%). No risk factor was significantly associated with herd seroprevalence at P< or = 0.05 in all opossum districts. Our results suggest that equids living in areas with large opossum populations might be infected with S. neurona from multiple sources.
A three-year grazing experiment (1998-2000) was conducted with first-season grazing cattle (FSGC) on improved pastures in central-eastern Sweden. Comparison was made between five groups with 10 calves in each group where four of these were set stocked and either (1) untreated, (2) ivermectin bolus treated, (3) subjected to biological control with the nematophagous fungus Duddingtonia flagrans, or (4) treated with a copper wire particle bolus. The fifth treatment was an evasive grazing strategy, whereby untreated calves were turned out onto pasture used by older cattle the previous year and then these calves were moved to silage aftermath in mid-July. To introduce low-levels of parasite infection to the experiment, each animal received a 'priming dose' of approximately 5,000 Ostertagia ostertagi and 5,000 Cooperia oncophora infective third stage larvae immediately prior to the start of the first grazing year of the trial. Results showed that efficient and sustainable parasite control of FSGC was possible to achieve without the use of anthelmintics by using turnout pastures that the previous year had been grazed by older cattle, in combination with a mid-July move to aftermath leys. Biological control also proved beneficial but the efficacy was impaired if high faecal egg counts coincided with rapid dung pat degradation due to heavy rainfall. No indication of parasite control was observed with the copper wire particle bolus. It was also demonstrated that the impact of gastrointestinal (GI) parasitism varied between years and that the level of overwintering contamination is important but likewise, is unpredictable. Although faecal egg counts in 1999 were low, due both to a delayed turnout and drought for the major part of the grazing season, deposited eggs successfully developed to infective larvae and overwintered in large numbers. The population of overwintered infective larvae at the time of turnout in early May played an important role in the course of infection in 2000 and resulted in an average 65 kg advantage of the ivermectin treated calves compared with the untreated calves.Thus, this three-year grazing experiment has emphasised the importance of subclinical gastrointestinal nematode infections in FSGC in Sweden. In addition, the study has shown that adequate parasite control may be achievable without the use of anthelmintics.