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51.
Karin Östensson Vo Lam Natahlie Sjögren Ewa Wredle 《Tropical animal health and production》2013,45(4):979-986
Dairy production is not traditional in Vietnam. The farmers have little practical knowledge and udder health control is generally lacking. In order to give the farmers appropriate advice, knowledge about the distribution of udder pathogens is crucial. The aim of the study was to investigate the prevalence of sub-clinical mastitis and to identify udder pathogens isolated from smallholder dairy herds in Southern Vietnam. Twenty farms with a herd somatic cell count (SCC) ranging from low (≤400?×?103?cells/mL) to high (>400?×?103?cells/mL) were randomly selected. Milk samples were collected from 458 quarters of 115 clinically healthy cows. SCC was analyzed on farm by a portable cell counter. Bacteriological samples were taken using Mastistrip© cassettes and sent to Sweden for examination. For all herds the mean herd SCC was 632?×?103/mL milk. The prevalence of subclinical mastitis at quarter SCC basis was 63.2 % and at cow basis 88.6 %. Only 40 % of all cows were bacteriologically negative in all quarters. Streptococcus agalactiae was the most commonly found bacteria species, isolated from 96 of the 458 quarter samples, in 13 of the 20 farms. The results indicate pronounced subclinical mastitis problems among the dairy cows in this region mainly due to infections with S. agalactiae. The high prevalence of this highly contagious pathogen is probably attributable to the generally poor milking hygiene and low awareness of proper measures to prevent occurrence and spread of udder infections. A strict, targeted action program for the herds in this area is required in order to lower the prevalence of subclinical mastitis. 相似文献
52.
Karin H. Jensen Lene J. Pedersen Anne Mette Giersing Hageisø Knud Erik Heller Erik Jørgensen Jan Ladewig 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):276-285
Abstract Ninetysix pigs, half females and half castrated males from 12 litters, were housed in 24 groups of 4 litter mates (2 females, 2 castrates). The pigs were weaned at 4 weeks of age and from the age of 115 days half of the groups were subjected to a schedule of unpredictable, inescapable electroshocks for 33 days, and half served as control. The adrenocortical reactivity to ACTH stimulation and to an emotional stressor (the procedure associated with initiation of blood collection) was measured in females, whereas the behavioural and pituitary-adrenocortical reactivity to an open field test was measured in castrates, as was the behavioural reactivity in a social test. Intermittent stress increased adrenocortical reactivity to ACTH stimulation significantly. This effect was present within the first week of intermittent stress (p < 0.06), but no difference was found after 4–5 weeks of stress. In contrast, the adrenocortical reactivity to additional emotional stressors was unaffected by stress after one week of intermittent stress, but increased after 4–5 weeks. In the open field test, centre location increased after one week of intermittent stress, whereas exploration decreased and walking and ambulation increased after 4–5 weeks of stress. In addition, 4–5 weeks of intermittent stress decreased aggressiveness in a social test. In conclusion, the change in reactivity to an additional acute stressor during intermittent stress appeared in different variables and contexts at different times during the course of intermittent stress. Thus, assessment of stress based on changed reactivity has to include several distinct measures of behavioural and hormonal reactivity. 相似文献
53.
Wei Xinghu Liu Shujuan Müller Karin Song Zhaoliang Guan Gongcou Luo Jiafa Wang Hailong 《Journal of Soils and Sediments》2019,19(11):3797-3804
Journal of Soils and Sediments - Acid rain events in Yuebei, a region of northern Guangdong Province, China, have been increasing due to rapid urbanization in recent years. A three-year study was... 相似文献
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56.
Eeckhaut E Struijs K Possemiers S Vincken JP Keukeleire DD Verstraete W 《Journal of agricultural and food chemistry》2008,56(12):4806-4812
Estrogenic plant compounds from the human diet such as the lignan secoisolariciresinol diglucoside (SDG, 1) can exert biological activity in the human body upon ingestion and bioactivation to enterodiol (END, 5) and enterolactone (ENL, 6). Bioavailability of lignans is influenced by the food matrix and gut microbial action, of which the latter is subject to a large interindividual variation. In this study, the fate of the lignan precursor SDG, present in the lignan macromolecule of flax seed ( Linum usitatissimum), was determined during an artificial stomach and small intestinal digestion and during metabolism by two different enterolignan phenotypes in a TWINSHIME environment (TWIN Simulator of the Human Intestinal Microbial Ecosystem). The lignan macromolecule acted as a delivery system of SDG in the large intestine. SDG was only hydrolyzed into secoisolariciresinol (SECO, 2) through microbial action in the ascending colon, after which it was bioactivated into enterolignans from the transverse colon onward. Single demethylation was a first step in the bioactivation, followed by dehydroxylation. Enterolignan phenotypes remained stable throughout the experimental period. The establishment of END and ENL production equilibria reflected the subdominance of ENL-producing bacteria in the gastrointestinal tract. 相似文献
57.
Casparus J. BRINK Anneke POSTMA Etienne SLABBERT Ferdinand POSTMA A. Muthama MUASYA Karin JACOBS 《土壤圈》2020,30(6):778-790
Aspalathus linearis is a commercially important plant species endemic to the Cape Floristic Region of South Africa and is used to produce a herbal tea known as rooibos tea. Symbiotic interactions between A. linearis and soil bacteria play an important role in the survival of Aspalathus plants in the highly nutrient-poor, acidic fynbos soil. The aim of this study was to characterize and compare rhizosphere and bulk soil bacterial communities associated with natural and commercially grown A. linearis, as well as the effect of seasonal changes on these communities. Bacterial communities were characterized using high throughput amplicon sequencing, and their correlations with soil chemical properties were investigated. The N-fixing bacterial community was characterized using terminal restriction fragment length polymorphism and real time quantitative polymerase chain reaction. Actinobacteria, Proteobacteria, and Acidobacteria were the most dominant bacterial phyla detected in this study. Highly similar bacterial communities were associated with natural and commercially grown plants. Significant differences in the bacterial community were observed between rhizosphere and bulk soils collected in the dry season, while no significant differences were detected in the wet season. This study provides insights into bacterial community structure and potential factors shaping bacterial community structure with commercially important A. linearis. 相似文献
58.
Suchodolski JS Morris EK Allenspach K Jergens AE Harmoinen JA Westermarck E Steiner JM 《Veterinary microbiology》2008,132(3-4):379-388
Limited information is available about the prevalence and phylogenetic classification of fungal organisms in the gastrointestinal tract of dogs. Also, the impact of fungal organisms on gastrointestinal health and disease is not well understood. The aim of this study was to evaluate the prevalence of fungal DNA in the small intestine of healthy dogs and dogs with chronic enteropathies. Small intestinal content was analyzed from 64 healthy and 71 diseased dogs from five different geographic locations in Europe and the USA. Fungal DNA was amplified with panfungal primers targeting the internal transcriber spacer (ITS) region. PCR amplicons were subjected to phylogenetic analysis. Fungal DNA was detected in 60.9% of healthy dogs and in 76.1% of dogs with chronic enteropathies. This prevalence was not significantly different between the two groups (p=0.065). Fungal DNA was significantly more prevalent in mucosal brush samples (82.8%) than in luminal samples (42.9%; p=0.002). Sequencing results revealed a total of 51 different phylotypes. All sequences belonged to two phyla and were classified as either Ascomycota (32 phylotypes) or Basidiomycota (19 phylotypes). Three major classes were identified: Saccharomycetes, Dothideomycetes, and Hymenomycetes. The most commonly observed sequences were classified as Pichia spp., Cryptococcus spp., Candida spp., and Trichosporon spp. Species believed to be clinically more important were more commonly observed in diseased dogs. These results indicate a high prevalence and diversity of fungal DNA in the small intestine of both healthy dogs and dogs with chronic enteropathies. The canine gastrointestinal tract of diseased dogs may harbor opportunistic fungal pathogens. 相似文献
59.
Soy-derived isoflavones have been reported to be specific inhibitors of protein tyrosine kinases like the type 1 insulin-like growth factor receptor (IGF-1R) and the epidermal growth factor receptor (EGFR). This study was conducted to investigate, whether IGF-I and EGF stimulate porcine myoblast growth and whether the responses are influenced by isoflavones. Satellite cell-born myoblasts derived from the semimembranosus muscle of newborn piglets were treated for 26h with IGF-I or EGF alone and in combination with genistein or daidzein. The DNA amount was measured and DNA synthesis was recorded as 6 h-[(3)H]thymidine incorporation during exponential growth in serum-free basal medium. IGF-I and EGF synergistically stimulated DNA synthesis of porcine myoblast with EGF causing a greater response. Genistein (100mumol/l) effectively reduced the growth factor-mediated DNA synthesis, which was associated with an inhibition of growth factor receptor protein expression. In response to daidzein no reduction in growth factor-mediated DNA synthesis was found. Daidzein (1; 10mumol/l) combined with IGF-I caused even a slight increase in DNA amount compared with the untreated control. The expression of the IGF-1R precursor protein was reduced with 10 and 100mumol/l daidzein, whereas the EGFR expression remained unchanged with daidzein. The results suggest that dietary isoflavones may interact with growth factor-induced stimulation of pig skeletal muscle growth. 相似文献
60.
Allenspach K Lomas B Wieland B Harris T Pressler B Mancho C Lees GE Vaden SL 《American journal of veterinary research》2008,69(10):1301-1304