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1.
Naití A. Morales Maike Heidemeyer Robert Bauer Sebastian Hernández Enzo Acuña Simon Jan van Gennip Alan M. Friedlander Carlos F. Gaymer 《水产资源保护:海洋与淡水生态系统》2021,31(2):340-355
- Marine protected areas (MPAs) are becoming a widely used tool for the conservation of biodiversity and for fishery management; however, most of these areas are designed without prior knowledge of the basic ecological aspects of the species that they are trying to protect.
- This study investigated the movement of two top predators: the Galapagos shark, Carcharhinus galapagensis, and the yellowtail amberjack, Seriola lalandi, in and around the Motu Motiro Hiva Marine Park (MMHMP) using MiniPAT satellite tags to determine the effectiveness of this MPA for the protection of these species.
- The Galapagos sharks (n = 4) spent most of their tag deployment periods inside the MMHMP. However, high intraspecific variability was observed in their movement dynamics. Daily individual maximum movements ranged from 17 to 58 km and the maximum distance from Salas y Gómez Island, the only emergent island within the MMHMP, ranged from 31 to 139 km.
- The maximum linear distance travelled for a female juvenile Galapagos shark (152 cm total length) was 236 km, which is greater than the maximum distance previously documented for juveniles of this species (<50 km).
- For the yellowtail amberjack (n = 1), 91% of the satellite geolocations were within the MMHMP, with a maximum daily distance travelled of 6 km. The maximum distance travelled between points was 111 km and the maximum distance from Salas y Gómez Island was 62 km.
- All archival tagged fish spent most of their time at depths of <50 m and never left the epipelagic zone. Daytime versus night-time differences were pronounced in all individuals but showed high interindividual variability.
- This study provides a baseline on the movement of these two top predators in the MMHMP and provides valuable insights for the creation of MPAs in the region and elsewhere.
2.
Nielsen NS Petersen A Meyer AS Timm-Heinrich M Jacobsen C 《Journal of agricultural and food chemistry》2004,52(25):7690-7699
The influence of the addition of metal chelators on oxidative stability was studied in a milk drink and in a mayonnaise system containing highly polyunsaturated lipids. Milk drinks containing 5% (w/w) of specific structured lipid were supplemented with lactoferrin (6-24 muM) and stored at 2 degrees C for up to 9 weeks. Mayonnaise samples with 16% fish oil and 64% rapeseed oil (w/w) were supplemented with either lactoferrin (8-32 muM), phytic acid (16-124 muM), or EDTA (16-64 muM) and were stored at 20 degrees C for up to 4 weeks. The effect of the metal chelators was evaluated by determination of peroxide values, secondary volatile oxidation products, and sensory analysis. Lactoferrin reduced the oxidation when added in concentrations of 12 muM in the milk drink and 8 muM in the mayonnaise, whereas it was a prooxidant at higher concentrations in both systems. In mayonnaise, EDTA was an effective metal chelator even at 16 muM, whereas phytic acid did not exert a distinct protective effect against oxidation. The differences in the equimolar effects of the metal chelators are proposed to be due to differences in their binding constants to iron and their different stabilities toward heat and low pH. 相似文献
3.
Maike?Krauss Hans-Martin?KrauseEmail author Simone?Spangler Ellen?Kandeler Sebastian?Behrens Andreas?Kappler Paul?M?der Andreas?Gattinger 《Biology and Fertility of Soils》2017,53(1):49-59
Since the development of effective N2O mitigation options is a key challenge for future agricultural practice, we studied the interactive effect of tillage systems on fertilizer-derived N2O emissions and the abundance of microbial communities involved in N2O production and reduction. Soil samples from 0–10 cm and 10–20 cm depth of reduced tillage and ploughed plots were incubated with dairy slurry (SL) and manure compost (MC) in comparison with calcium ammonium nitrate (CAN) and an unfertilized control (ZERO) for 42 days. N2O and CO2 fluxes, ammonium, nitrate, dissolved organic C, and functional gene abundances (16S rRNA gene, nirK, nirS, nosZ, bacterial and archaeal amoA) were regularly monitored. Averaged across all soil samples, N2O emissions decreased in the order CAN and SL (CAN?=?748.8?±?206.3, SL?=?489.4?±?107.2 μg kg?1) followed by MC (284.2?±?67.3 μg kg?1) and ZERO (29.1?±?5.9 μg kg?1). Highest cumulative N2O emissions were found in 10–20 cm of the reduced tilled soil in CAN and SL. N2O fluxes were assigned to ammonium as source in CAN and SL and correlated positively to bacterial amoA abundances. Additionally, nosZ abundances correlated negatively to N2O fluxes in the organic fertilizer treatments. Soils showed a gradient in soil organic C, 16S rRNA, nirK, and nosZ with greater amounts in the 0–10 than 10–20 cm layer. Abundances of bacterial and archaeal amoA were higher in reduced tilled soil compared to ploughed soils. The study highlights that tillage system induced biophysicochemical stratification impacts net N2O emissions within the soil profile according to N and C species added during fertilization. 相似文献
4.
Whereas in former times horses were reserved primarily for people involved in
agriculture, elite equestrians or the military, nowadays equestrian sport has become an
activity for people with a wide variety of backgrounds. However, as more and more people
become involved with equestrian sport today, the knowledge concerning animal husbandry in
general is diminishing due to an alienation from agricultural themes in modern societies.
As a consequence, this development affects both riding ability and the appraisal of
horses, especially with respect to the purchase of horses. In order to analyse which
factors influence purchase decisions in the horse market in conjunction with equestrian
experience, 739 horse riders were surveyed on their purchase behaviour in this study.
Using cluster analysis, a typology was generated that provides a differentiated picture of
the preferences of the various rider groups. Three clusters were distinguished: the
“amateurs”, the “experienced” and the “experts”. Taking personal horse riding proficiency
into account, it could be concluded that especially the “amateur” group required objective
criteria for the evaluation of a horse they are considering purchasing. Alongside
“measureable” qualities, such as previous showing success or the level of training of the
horse, also other attributes such as the simple handling of the horse should be taken into
consideration. As particularly the “amateur” group in equestrian sport is increasing in
numbers, it is therefore advisable when preparing a horse for sale to align oneself to the
needs of this customer segment in order to ensure an effective and targeted marketing of
horses. 相似文献
5.
With changes in food preferences and life styles,more and more attentions have been focused on healthier food.Nowadays,resistant starch(RS)which can resist digestion in the human intestine has been recognized and accepted.High RS diet shows great benefit for the human health,and breeding high RS rice variety is a great target for realizing dietary intervention.To provide guidance for RS improvement in rice,this review summarized the unique physiochemical properties of RS and the possible approaches,i.e.genetic regulation,for enhancing RS content in rice,and proposed the potential ways to obtain rice variety with high RS content. 相似文献
6.
Marion Piechotta Lars Holzhausen Marcelo Gil Araujo Maike Heppelmann Anja Sipka Chistiane Pfarrer Hans-Joachim Schuberth Heinrich Bollwein 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(3):343-352
Cows with different Insulin-like Growth Factor-I (IGF-I) concentrations showed comparable expression levels of hepatic growth hormone receptor (GHR). Suppressor of cytokine signaling 2 (SOCS2), could be responsible for additional inhibition of the GHR signal cascade. The aims were to monitor cows with high or low antepartal IGF-I concentrations (IGF-Ihigh or IGF-Ilow), evaluate the interrelationships of endocrine endpoints, and measure hepatic SOCS2 expression. Dairy cows (n = 20) were selected (240 to 254 days after artificial insemination (AI)). Blood samples were drawn daily (day -17 until calving) and IGF-I, GH, insulin, thyroid hormones, estradiol, and progesterone concentrations were measured. Liver biopsies were taken (day 264 ± 1 after AI and postpartum) to measure mRNA expression (IGF-I, IGFBP-2, IGFBP-3, IGFBP-4, acid labile subunit (ALS), SOCS2, deiodinase1, GHR1A). IGF-I concentrations in the two groups were different (p < 0.0001). However, GH concentrations and GHR1A mRNA expression were comparable (p > 0.05). Thyroxine levels and ALS expression were higher in the IGF-Ihigh cows compared to IGF-Ilow cows. Estradiol concentration tended to be greater in the IGF-Ilow group (p = 0.06). It was hypothesized that low IGF-I levels are associated with enhanced SOCS2 expression although this could not be decisively confirmed by the present study. 相似文献
7.
Maraike Wiebe Christiane Pfarrer Lara Górriz Martín Marion Schmicke Martina Hoedemaker Heiner Bollwein Maike Heppelmann 《Reproduction in domestic animals》2021,56(1):172-182
Metritis is an important disorder in dairy cows during the early postpartum period. Myometrial contractility is a prerequisite for uterine involution; however, very scanty literature is available about the effect of metritis on this process and endocrine responsiveness. This study was aimed to evaluate the effect of inflammation on uterine contractility in vitro, and the inflammation was induced by incubating myometrial strips with lipopolysaccharides (LPS). Myometrial samples were collected from 17 healthy Holstein Friesian cows during caesarean section. Eight longitudinal strips from each cow were incubated in organ baths with LPS concentrations of 0 (LPS0), 0.1 (LPS0.1), 1 (LPS1) and 10 µg/ml (LPS10). Spontaneous contractility and contractility induced by increasing concentrations of oxytocin (10–10 – 10–7 mol/L) were recorded during nine 30-min intervals (T1 to T9). The minimum amplitude (minA), maximum amplitude (maxA), mean amplitude (meanA) and area under the curve (AUC) were calculated for each time interval. LPS had an effect (p ≤ .05) on maxA, meanA and AUC. In T1, myometrial strips incubated with LPS0.1 and LPS1 had higher (p ≤ .05) maxA, meanA and AUC than the strips incubated with LPS0. In T9 without oxytocin, LPS0 led to higher (p ≤ .05) maxA, meanA and AUC than LPS0.1 and LPS1. In T8 and T9 with oxytocin, LPS1 had lower (p ≤ .05) maxA, meanA and AUC than the other LPS concentrations. Interestingly, the results show that LPS has a transient positive effect on myometrial contractility in vitro and that this effect is dependent on LPS concentration and duration of incubation. 相似文献
8.
Maike Schaefer 《Water, air, and soil pollution》2005,165(1-4):265-278
Despite the cutback of the use of antifouling paints containing tributyltin (TBT), harbour sediments are still “hot spots” for organotin pollution, which is one of the most toxic substances for aquatic organisms. Harbours have to be freed constantly of suspended sediments, to guarantee unhindered shipping. The deposition of these TBT contaminated sediments on rinsing fields is supposed to comprise a minimisation of the risk potential for humans and environment. To investigate if TBT contaminated sediment might present a hazard to the existing soil fauna, a risk assessment with earthworms was performed. The original TBT contaminated sediment induced 94% mortality, compared to 2% in the uncontaminated standard Lufa soil. It was assumed that the high salinity (23 dS/m) was the reason for the mortality rather than the TBT concentration of 600 μg/kg soil (dry weight). To reduce the soil salinity, the TBT substrate was first washed with deionised water and then mixed with the uncontaminated artificial OECD soil (=TBTmix), which resulted, however, in a lower TBT concentration (132 μg/kg soil dw.). The uncontaminated OECD reference soil resulted in high earthworm mortality (34%). Despite the reduced salinity (10 dS/m) and lower TBT concentration, the TBTmix substrate induced high mortality rates (42%), reduced reproduction (17% compared to the control) and resulted in a significant substrate avoidance of 92%. Consequently, the landfilling of the TBT contaminated harbour sludge might (i) present a hazard to the existing soil fauna at the rinsing fields due to high salinity and the TBT contamination, and (ii) a quick recolonisation of the contaminated substrate by earthworms can not be expected. 相似文献
9.
Berndt‐Michael Wilke Maike Mai Andreas Gattinger Michael Schloter Ping Gong 《植物养料与土壤学杂志》2005,168(5):668-675
The aim of the investigation was to compare effects of fresh and aged amendments of copper (Cu) on the active, aerobic, heterotrophic microbial biomass by respiration and potential‐nitrification measurements and on microbial‐community structure by means of phospholipid‐fatty‐acid (PLFA) analyses. An Ap horizon (10–20 cm) of a Luvisol was used for the experiments. Fresh copper amendments were carried out by spraying a CuCl2 solution on the soil. Aged heavy‐metal amendments were achieved by mixing the control soil with monocontaminated soil derived from an abandoned site in Denmark which has been used as a wood‐preservation plant. As expected, fresh contaminations were more effective to reduce potential nitrification and respiration than aged contaminations if the total Cu concentration (Cut) in soils is considered. There were no differences between aged and fresh contaminations if their effects were referred to NH4Cl‐extractable concentrations (CuAN). The lowest concentration reducing cumulative substrate‐induced respiration (CR) amounted to 0.33 mg CuAN (kg dm)–1. PLFA analyses revealed Cu contaminations to decrease mainly aerobic bacteria. Effects were more pronounced using the contaminated soil as an inoculum. Apparently the duration of contamination is more important to the change of microbial‐community structure than the actual availability of the contaminant. 相似文献
10.
Maike HEPPELMANN Karoline KRACH Lars KRUEGER Philipp BENZ Kathrin HERZOG Marion PIECHOTTA Martina HOEDEMAKER Heinrich BOLLWEIN 《The Journal of reproduction and development》2015,61(6):565-569
The objective of this study was to examine the effects of metritis and subclinical hypocalcemia on reduction
of uterine size in dairy cows using ultrasonography and sonomicrometry. Four piezoelectric crystals were
implanted via laparotomy into the myometrium of the pregnant uterine horn of 12 pluriparous Holstein Friesian
cows 3 weeks before the calculated calving date. Sonometric measurements were conducted daily from 2 days
before parturition (= Day 0) until Day 14 after calving and then every other day until Day 28. Distances
between adjacent crystals were expressed in relation to reference values obtained before calving. The diameter
of the formerly pregnant uterine horn was measured using transrectal B-Mode sonography starting on Day 10.
Cows were retrospectively divided into the following groups: cows without metritis (M–; n = 7), cows with
metritis (M+; n = 5), cows with normocalcemia (SH–; Ca > 2.0 mmol/l on Days 1 to 3; n = 5) and cows with
subclinical hypocalcemia (SH+; Ca < 2.0 mmol/l in at least one sample between Days 1 and 3; n = 7).
Metritis did not affect (P > 0.05) sonometric measurements, but the diameter of the formerly pregnant horn
was larger (P ≤ 0.05) between Days 15 and 21 in M+ cows than in M‒ cows. Reduction in uterine length in
hypocalcemic cows was delayed (P ≤ 0.05) between Days 8 and 21 compared with normocalcemic cows, but the
uterine horn diameter was not related to calcium status. In conclusion, both diseases affected reduction of
uterine size until Day 28. Cows with metritis had a larger uterine diameter, possibly attributable to
accumulation of lochia, and cows with subclinical hypocalcemia had delayed reduction of uterine length,
presumably related to reduction of myometrial contractility. 相似文献