Effect of wilting,silage additive,PEG treatment and tannin content on the distribution of N between different fractions after ensiling of three different sainfoin (Onobrychis viciifolia) varieties     

M. M. Lorenz  T. Eriksson  P. Udn 《Grass and Forage Science》2010,65(2):175-184

Sainfoin (Onobrychis viciifolia) is a tanniniferous, leguminous plant that has potentially beneficial effects on protein utilization in ruminants. As ensiling causes protein breakdown and elevated levels of buffer soluble N (BSN), we studied the distribution of N before and after ensiling sainfoin. Three varieties of sainfoin were either direct‐cut and frozen directly or wilted and frozen before later ensiling in mini‐silos with and without acidification with Promyr (PM; an acidifying commercial mixture of propionic and formic acid) and with or without polyethylene glycol (PEG). Extractable tannins (ET) and protein‐bound tannins (PBT) were measured with an HCl/butanol method in an attempt to correlate tannin levels to N fractions. The sainfoin silages showed good ensiling characteristics and had relatively high concentrations of undegraded protein. The effect of wilting on BSN levels (g/kg N) was dependent on sainfoin variety (P < 0·001). PEG increased and PM decreased the level of BSN in the silages (P < 0·001). PM treatment also produced less non‐protein N and ammonia‐N (P < 0·05) as compared with no additive. Addition of PEG to the silage increased the BSN‐proportion 1·8‐ and 2·6‐fold for both DM stages. A strong tannin‐protein binding effect is, therefore, confirmed in sainfoin. However, correlations between tannin levels (ET and PBT) and BSN were poor in the (non‐PEG) silages, indicating either that the HCl/butanol method is unsuitable for measuring tannin in silages or that qualitative attributes of tannins are more relevant than quantitative. The HCl/butanol method seems therefore not to be useful to predict degradation of protein in sainfoin silages.  相似文献   

A review of the role of excess soil moisture conditions in constraining farm practices under Atlantic conditions     

R. P. O. Schulte  R. Fealy  R. E. Creamer  W. Towers  T. Harty  R. J. A. Jones 《Soil Use and Management》2012,28(4):580-589

The Less Favoured Area (LFA) scheme is a major element of the EU Rural Development Policy, aimed at supporting farming in areas with natural handicaps or low soil productivity. It has been in place since 1975 and accounts for 14% of total Community funding. In 2003, the European Court of Auditors recommended that the socio‐economic criteria on which the current scheme is based be replaced by biophysical criteria. Reviews of the proposals suggest that in Atlantic climates of Northwest Europe, the new criteria do not delineate adequately areas where agricultural productivity is constrained by the biophysical environment and that such areas are instead demarcated by the occurrence of excess soil moisture conditions. In this paper, we review the impact of excess soil moisture conditions on the sustainability of farming systems and their role in constraining strategic and tactical farm management practices. In particular, we review the scientific evidence on the impact of excess soil moisture conditions on herbage growth, herbage utilization, farm operations and environmental sustainability. On the basis of this, we propose an additional biophysical criterion for the new delineation of LFAs, namely the length of time that soil water is in excess of field capacity (‘field capacity days’). While there is no clear threshold for field capacity days above which agricultural sustainability is acutely constrained, the evidence reviewed in this paper suggests that the sustainability of intensive livestock farming and tillage systems is particularly challenging in scenarios where the 80 percentile of field capacity days exceeds 220–230 days.  相似文献   

Contrasting population demographics and reproductive investment of white crappie in three eutrophic reservoirs     

P. H. Michaletz 《Fisheries Management and Ecology》2013,20(1):1-9

Abstract White crappie, Pomoxis annularis Rafinesque, provides important sport fisheries across North America but sometimes exhibits slow growth and fails to reach sizes acceptable to anglers. Three dissimilar white crappie populations were studied to assess whether differences in growth were associated with size and age at maturity and subsequent larval production. Similar to other species, female white crappie matured at younger ages and smaller sizes and contained larger ovaries in the population with the slowest growth; this population also had the lowest annual mortality. Larval production (number m^?3) in this population was intermediate to that of the other populations. Attempts to improve growth of white crappie in the slow‐growing population will probably be hindered by these individuals’ greater reproductive investment, which reduces the amount of energy available for somatic growth.  相似文献   

A new Barbus minnow (Pisces,Cyprinidae) from the eastern Cape Province,South Africa     

P.H. Skelton 《African Zoology》2013,48(3):188-193

A new cyprinid minnow taken from a tributary of the Kei River system, eastern Cape Province, Barbus amatolicus sp. nov., is described. The Amatola barb is most similar to the widespread and sympatric chubbyhead barb (Barbus anoplus) and the redtail barb (Barbus gumeyl) but differs most clearly in male secondary sexual characteristics (breeding colours and nuptial tubercles).  相似文献   

The Standardization of an Apparatus for the Mixing of Soil Samples for Nematode Extractions     

J P Furstenberg 《African Zoology》2013,48(2):165-173

Quantitative determination of nematode populations in soils frequently necessitates the mixing of representative soil samples to form a homogeneous, compound sample from which the nematodes are extracted. A mixing apparatus was developed and standardized with the aid of a spectrophotometric technique by which the dispersion of a dye through the soil during mixing could be determined. It was found that the mixer is most suitable for use on sandy loam soils. Optimal mixing is obtained at a speed of 15 rpm for 2 minutes. Under these conditions mechanical damage to nematodes during mixing is minimal.  相似文献   

Effects of Municipal Solid Waste Compost on Soil Properties and Vegetables Growth     

G. V. Giannakis  N. N. Kourgialas  N. P. Nikolaidis  N. Kalogerakis 《Compost science & utilization》2013,21(3):116-131

ABSTRACT

This work investigates the impact of municipal solid waste compost (MSW-compost) application (0, 50, and 100 t/ha) on the growth, and on nutrient and trace elements content in lettuce and tomato plants grown in large, 40-L pots. Our findings showed inhibition of plants’ growth with increasing dose of MSW-compost, compared to plants receiving conventional fertilization. Growth inhibition was associated with a sharp decrease in soil NO₃–N content. On the other hand, a slower decrease in soil NO₃–N content occurred in non-planted pots amended with MSW-compost. These findings provide evidence that N immobilization and/or decreased N mineralization were responsible for inhibited growth by constraining N availability. With regard to the other macro-nutrients, K, P, Mg, Ca, and Fe, their contents in leaves of both crops were maintained at optimum levels. Higher zinc and copper content was measured in leaves of both crops but they did not exceed the optimum range for growth. No accumulation of trace elements was found in the fruits. The content of heavy metals in the tissues of plants grown in MSW-compost amended soil, remained at levels similar to those of the non-amended soil, suggesting that they do not pose a significant risk either for plant growth or public health. The findings of our study suggest that further emphasis should be given on the investigation of the factors regulating N mineralization and availability in order to avoid reductions in crop yield.  相似文献   

A Review of the Culture and Diseases of Redclaw Crayfish Cherax quadricarinatus (Von Martens 1868)     

Imad P. Saoud  Joly Ghanawi  Kenneth R. Thompson  Carl D. Webster 《Journal of the World Aquaculture Society》2013,44(1):1-29

  相似文献   

Orbital apex syndrome secondary to an orbital sarcoma in a dog     

Jayden Robert  Filipe Espinheira Gomes  Ian Porter  Julia P. Sumner 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(1):27

A 12-year-old castrated male cocker spaniel dog was presented with a 4-week history of left episcleral injection and pawing at the face. Clinical examination findings included left internal and external ophthalmoplegia, left dorsal strabismus, pain opening the mouth, and intermittent amaurosis. Imaging studies revealed a left orbital apex mass with adjacent sphenoid bone lysis and extension into the cranial cavity. A left exenteration was performed and histopathology confirmed an orbital soft tissue sarcoma.Key clinical message:This report describes an orbital tumor causing orbital apex syndrome. This condition should be differentiated from cavernous sinus syndrome as the latter does not course with optic neuropathy.  相似文献   

Vitamin and mineral supplementation and rate of gain during the first trimester of gestation affect concentrations of amino acids in maternal serum and allantoic fluid of beef heifers     

Ana Clara B Menezes  Kacie L McCarthy  Cierrah J Kassetas  Friederike Baumgaertner  James D Kirsch  Sheri Dorsam  Tammi L Neville  Alison K Ward  Pawel P Borowicz  Lawrence P Reynolds  Kevin K Sedivec  J Chris Forcherio  Ronald Scott  Joel S Caton  Carl R Dahlen 《Journal of animal science》2021,99(2)

The objective of this study was to evaluate the effects of feeding vitamin and mineral (VTM) supplement and (or) rate of gain (GAIN) during early gestation on amino acid (AA) concentrations in allantoic fluid (ALF) and amniotic fluid (AMF) and maternal serum. Seventy-two crossbred Angus heifers (initial BW = 359.5 ± 7.1 kg) were randomly assigned to one of four treatments in a 2 × 2 factorial arrangement with main effects of VTM supplement (VTM or NoVTM) and rate of gain (GAIN; low gain [LG], 0.28 kg/d, vs. moderate gain [MG], 0.79 kg/d). The VTM treatment (113 g•heifer⁻¹•d⁻¹, provided macro and trace minerals and vitamins A, D, and E to meet 110% of the requirements specified by the NASEM in Nutrient requirements of beef cattle. Washington, DC: The National Academies Press. doi:10.17226/19014, 2016) was initiated 71 to 148 d before artificial insemination (AI). To complete the factorial arrangement of treatments, at breeding heifers were either maintained on the basal diet (LG), or received MG diet which was implemented by adding a protein/energy supplement to the LG diet. Thirty-five gestating heifers with female fetuses were ovariohysterectomized on d 83 of gestation and maternal serum, ALF, and AMF were collected. Samples were analyzed for concentrations of neutral AA: Ala, Asn, Cys, Gln, Gly, Ile, Leu, Met, Phe, Pro, Ser, Thr, Trp, Tyr, and Val; cationic AA: Arg, His, and Lys; and anionic AA: Asp and Glu. In serum, a VTM × GAIN interaction (P = 0.02) was observed for Glu, with greater concentrations for VTM-LG than VTM-MG. Concentrations of serum Cys, Met, and Trp were greater (P ≤ 0.03) for MG than LG. In ALF, concentrations of Glu were affected by a VTM × GAIN interaction, where VTM-MG was greater (P < 0.01) than all other treatments. Further, ALF from VTM had increased (P ≤ 0.05) concentrations of His, Asp, and 12 of the 14 neutral AA; whereas GAIN affected concentrations of Arg, Cys, and Asp, with greater concentrations (P ≤ 0.05) in MG heifers. In AMF, AA concentrations were not affected (P ≥ 0.10) by VTM, GAIN, or their interaction. In conclusion, increased concentrations of AA in maternal serum and ALF of beef heifers were observed at d 83 of gestation in response to VTM supplementation and rate of gain of 0.79 kg/d, which raises important questions regarding the mechanisms responsible for AA uptake and balance between the maternal circulation and fetal fluid compartments.  相似文献   

The effects of maternal nutrition during the first 50 d of gestation on the location and abundance of hexose and cationic amino acid transporters in beef heifer uteroplacental tissues     

Matthew S Crouse  Kyle J McLean  Josephine Dwamena  Tammi L Neville  Ana Clara B Menezes  Alison K Ward  Lawrence P Reynolds  Carl R Dahlen  Bryan W Neville  Pawel P Borowicz  Joel S Caton 《Journal of animal science》2021,99(1)

We hypothesized that maternal nutrition during the first 50 d of gestation would influence the abundance of hexose transporters, SLC2A1, SLC2A3, and SLC2A5, and cationic amino acid transporters, SLC7A1 and SLC7A2, in heifer uteroplacental tissues. Angus-cross heifers (n = 43) were estrus synchronized, bred via artificial insemination, and assigned at breeding to 1 of 2 dietary intake groups (CON = 100% of requirements to achieve 0.45 kg/d of BW gain or RES = 60% of CON intake) and ovariohysterectomized on day 16, 34, or 50 of gestation (n = 6 to 9/d) in a completely randomized design with a 2 × 3 factorial arrangement of treatments. Uterine cross-sections were collected from the horn ipsilateral to the corpus luteum, fixed in 10% neutral buffered formalin, sectioned at 5 µm, and stained via immunofluorescence for transporters. For each image, areas of fetal membrane (FM; chorioallantois), luminal epithelium (ENDO), superficial glands (SG), deep glands (DG), and myometrium (MYO) were analyzed separately for relative intensity of fluorescence as an indicator of transporter abundance. Analysis of FM was only conducted for days 34 and 50. No transporters in target areas were influenced by a day × treatment interaction (P ≥ 0.06). In ENDO, all transporters were differentially abundant from days 16 to 50 of gestation (P ≤ 0.04), and SLC7A2 was greater (P = 0.05) for RES vs. CON. In SG, SLC7A1 and SLC7A2 were greater (P ≤ 0.04) at day 34 vs. day 16. In DG, SLC2A3 and SLC7A1 were greater (P ≤ 0.05) for CON vs. RES heifers; furthermore, SLC7A1 was greater (P < 0.01) at day 50 vs. days 16 and 34 of gestation. In MYO, SLC7A1 was greater (P < 0.01) for CON vs. RES and was greater (P = 0.02) at days 34 and 50 vs. day 16. There were no differences in FM (P ≥ 0.06). Analysis of all uterine tissues at day 16 determined that SLC2A1, SLC2A3, and SLC7A2 were all differentially abundant across uterine tissue type (P < 0.01), and SLC7A1 was greater (P = 0.02) for CON vs. RES. Analysis of all uteroplacental tissues at days 34 and 50 demonstrated that all transporters differed (P < 0.01) across uteroplacental tissues, and SLC7A1 was greater (P < 0.01) for CON vs. RES. These data are interpreted to imply that transporters are differentially affected by day of gestation, and that hexose and cationic amino acid transporters are differentially abundant across utero-placental tissue types, and that SLC7A1 is responsive to maternal nutritional treatment.  相似文献