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111.
Background
Heart rate and plasma cortisol concentration are often used in evaluation of physiological reactions to stress and fear, but arterial blood pressure is rarely measured in farm animals. Goats are prey animals and can be expected to react strongly to a predator, especially when they have kids. We hypothesized that exposure to a dog elicits a flight response during pregnancy and a fight response when goats have kids to defend. Arterial blood pressure and heart rate should increase in both these cases, due to a synchronized discharge of the sympathetic nervous system.Methods
Seven goats were exposed to a dog for 15 minutes at 12 ± 3 days before, and again at 10 ± 1 days after, parturition. Arterial blood pressure, heart rate, and activity were registered by telemetry. Behavioral data were collected during 5 minute sessions, followed by blood samples obtained via intrajugular catheters. Plasma cortisol concentration was analyzed by radioimmunoassay.Results
At the appearance of the dog, the mean arterial blood pressure of the goats increased from 90 ± 8 to 111 ± 8 mmHg (p < 0.001) during pregnancy and from 96 ± 8 to 108 ± 8 mmHg during lactation (p < 0.001). Heart rate did not change at dog exposure during lactation, but increased from 117 ± 6 to 126 ± 10 beats/min (p < 0.01) during pregnancy. Dog exposure resulted in plasma cortisol concentration increasing from 17 ± 1 to 43 ± 7 nmol/l (p < 0.01) during pregnancy and from 21 ± 1 to 49 ± 6 nmol/l (p < 0.01) during lactation. In response to the dog, goats vocalized at a higher frequency and started to ruminate later during lactation compared to pregnancy.Conclusions
When goats were exposed to a dog during pregnancy, their heart rate, blood pressure, and plasma cortisol increased, in contrast to lactation when only their blood pressure and plasma cortisol increased. However, when they were lactating, goats vocalized more and started to ruminate later compared to when they were pregnant. 相似文献112.
Late season production of raspberries and blackberries has become more common due to increased consumer demand and new production techniques, but information is scarce regarding the effect on nutritional quality, especially during storage. Antioxidant levels in berries can be influenced by pre-harvest climate conditions (light intensity, day length and temperature) and post-harvest storage time. This study analysed the effect of these factors on the content of different antioxidants (vitamin C, ellagic acid, anthocyanins and total phenolics) in raspberries (Rubus idaeus L. cv. Polka) and blackberries (Rubus fructicosus L. cv. Loch Ness) during storage. The analyses were performed using high performance liquid chromatography (HPLC) with photodiode array detection. Ellagic acid content during storage ranged between 104 and 114 mg/100 g fresh weight in raspberries and 172 and 182 mg/100 g fresh weight in blackberries. Anthocyanin content increased during storage from 64 to 77 mg/100 g fresh weight in raspberries, but decreased from 199 to 162 mg/100 g fresh weight in blackberries. Vitamin C content in raspberries ranged during storage between 22 and 28 mg/100 g fresh weight, but in blackberries values were lower (10–12 mg/100 g fresh weight). Significant changes in total phenolics and sugars occurred during different storage periods (0–9 or 10 days). The results suggest that late season raspberries and blackberries maintain high quality in terms of antioxidant content. 相似文献
113.
Karna Hansson Bengt A. OlssonMats Olsson Ulf JohanssonDan Berggren Kleja 《Forest Ecology and Management》2011,262(3):522-530
Soil properties were compared in adjacent 50-year-old Norway spruce, Scots pine and silver birch stands growing on similar soils in south-west Sweden. The effects of tree species were most apparent in the humus layer and decreased with soil depth. At 20-30 cm depth in the mineral soil, species differences in soil properties were small and mostly not significant. Soil C, N, K, Ca, Mg, and Na content, pH, base saturation and fine root biomass all significantly differed between humus layers of different species. Since the climate, parent material, land use history and soil type were similar, the differences can be ascribed to tree species. Spruce stands had the largest amounts of carbon stored down to 30 cm depth in mineral soil (7.3 kg C m−2), whereas birch stands, with the lowest production, smallest amount of litterfall and lowest C:N ratio in litter and humus, had the smallest carbon pool (4.1 kg C m−2), with pine intermediate (4.9 kg C m−2). Similarly, soil nitrogen pools amounted to 349, 269, and 240 g N m−2 for spruce, pine, and birch stands, respectively. The humus layer in birch stands was thin and mixed with mineral soil, and soil pH was highest in the birch stands. Spruce had the thickest humus layer with the lowest pH. 相似文献
114.
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116.
A Jöborn J C Olsson A Westerdahl P L Conway & S Kjelleberg 《Journal of fish diseases》1997,20(5):383-392
A non-virulent Carnobacterium sp., designated strain K1, isolated from the gastrointestinal tract of Atlantic salmon, Salmo salar L., which produced inhibitory substances against bacterial fish pathogens, was examined in vitro for characteristics important for the colonization of the fish gastrointestinal tract and in vivo for persistence in the tract after oral dosing. In vitro growth experiments showed that the cells of this strain were metabolically active in both the intestinal mucus and faeces from salmonids. The production of growth inhibitors against the two common fish pathogens Vibrio anguillarum and Aeromonas salmonicida by Carnobacterium sp. strain K1 was demonstrated in vitro in mucus and faecal extracts. Furthermore, it was demonstrated that the Carnobacterium cells remained viable in the gastrointestinal tract for several days and that no detrimental effect to the fish was observed as a result of the presence of the bacterium. 相似文献
117.
Kerstin Olsson 《Potato Research》1988,31(3):423-429
Summary The levels of incorporation of Mg and Ca into tuber cell walls and middle lamellae were compared with the intensity of attack
byPhoma exigua var.foveata (P.e.f.) (gangrene) andFusarium solani var.coeruleum (F.s.c.) (dry rot) in six genotypes varying in their levels of resistance. The Mg:Ca ratio was higher in those genotypes more resistant
toP.e.f., while the cation effect on attack byF.s.c was variable. Although genotype resistance may be improved by extra Mg bridges in the pectin structure the genotypic differences
in susceptibilty to gangrene could not be explained by differences in Mg content assessed from alcohol-insoluble solids. Analyses
of breeders' selections showed no general relationship between Mg or Ca contents and disease incidence. Therefore, genotypic
differences in incorporation of these cations could not be used for screening for improved resistance. 相似文献
118.
Jos A. M. Botermans Lotta Georgsson Björn R. Weström Anne-charlotte Olsson Jørgen Svendsen 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):250-262
The effect of feeding environment on individual pigs (small, medium and large barrows) housed in groups of 16 pigs was studied. The experiment comprised the following four treatments: trough feeding, four dry feeders, one dry feeder and one wet/dry feeder per 16 pigs, respectively. Performance, skin injuries, plasma cortisol, agonistic behaviour, ingestive behaviour and activity were studied. The effect of competition for feed was most clearly evident for the small pigs. The small animals in the one dry feeder treatment were forced to eat more during the night, had more forced withdrawals from the feeder, and tended to have more scratches and skin injuries than did the small animals in the four dry feeder treatment. It was concluded that this competition led to impaired well-being in the smallest pigs. No significant differences were detected in plasma cortisol levels, when comparing the different feeding systems within each pig size category. Trough feeding greatly affected pig feed intake pattern: during the growing period when pigs had ad libitum access to feed, the pigs fed in a trough ate mostly at feeding times, while the pigs in the four dry feeder treatment ate at times spread out over the entire 24 h period. It was concluded that there was a confounding effect between pig size category (small or large) and feeding system with regard to ingestive behaviour and aggressive interactions at feeding. 相似文献
119.
Gunnela M Gustafson Ingemar Olsson 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):10-19
The partitioning of nutrients and trace elements from feeds, drinking water and mineral supplements on growth, faeces and urine of growing cattle was studied with eight steers in a balanced Latin square design with two replicates, each comprising four treatments (diet compositions), four periods and four animals. The treatments were four rations with a silage proportion of 15, 30, 60 and 100% of the dry matter. Records were taken of the individual intake of silage, concentrates, mineral supplements and water, and excretions by collecting all urine and faeces. All feeds, urine, faeces and water were analysed for their content of Al, Ca, Cd, Cl, Co, Cu, Fe, K, Mg, Mn, Mo, N, Na, Ni, P, S, Se, and Zn. Elements that were mainly excreted in faeces (Ca, Cd, Cu, Fe, P, and Zn) tended to have a constant uptake in amount. As there is a fairly good correlation between DM consumption and faeces production, it is possible to estimate the amount of these elements excreted at farm level by analysing a faeces sample. Elements that are excreted in significant amounts in both faeces and urine (Cl, K, Mg, Mo, N, Na, S, and Se) tended to have a constant uptake over treatments as a fraction of the feed content. It is more difficult to estimate the amounts of these elements at farm level because it is more difficult to predict urine production than faeces production. 相似文献
120.
S.‐E. Olsson 《The Veterinary quarterly》2013,33(3):268-278
Summary Observations based on necropsy findings in 89 dogs with osteochondrosis are presented. Osteochondrosis was most common in the elbow joint, followed by the shoulder joint, the stifle and the hock joint. There were 59 male and 30 female dogs, and the mean age was 2 years. The high frequency of bilateral lesions and the occurrence of osteochondrosis in more than one pair of joints in 25 of the 89 dogs indicates that general factors are important. The various manifestations of osteochondrosis and their frequency are reported. Various local factors believed to be important for the occurrence of the lesions within the joints are also considered. 相似文献