Postpartum anoestrus in five seasonally‐calving dairy farms in Victoria,Australia          下载免费PDF全文

KL Plozza  DS Beggs  PD Mansell  MA Stevenson  CB Blackwood  MF Pyman 《Australian veterinary journal》2016,94(8):293-298

  相似文献   

Studies on developmental stages of the horse chestnut scale insect,Pulvinaria regalis Canard (Hom., Coccidae), in the open land and in the laboratory     

Prof. Dr. Ç. Şengonca  Dipl.-Ing. Agr. T. Faber 《Journal of pest science》1996,69(3):59-63

In the presented paper the development of horse chestnut scale insect,Pulvinaria regalis Canard, was studied a on red horse chestnut (Aesculus x carnea) in the urban area of Bonn. Secondly, the scale insect growth was determined on sycamore maple (Acer pseudoplatanus) and horse chestnut (Aesculus hippocastanum) at different temperatures in the laboratory.The field population displayed an insignificant linear increase in body length between July and beginning of December. No growth was observed between December and March but between mid of March and beginning of May the body size increased exponentially. By setting up a frequency distribution of the anal plate length and by simultaneous measurement of new and old anal plate during molting it was possible to separate different developmental stages. The length of the anal plates of first instar crawlers/settlers ranged between 0.030 and 0.054 mm, that of the second and third instar nymphs between 0.066 and 0.090 mm and 0.102 to 0.150 mm, respectively. The anal plate length of fourth instar adult females differed between 0.162 and 0.246 mm, whereas those of male puparians ranged between 0.075 and 0.098 mm. Since the cuticula ofP. regalis is very extensible, the separation of different developmental stages was only reliable by using the measure of the strongly sclerosed anal plate. Until 12. August first instar crawlers/settlers and till 29. September second instar nymphs were observed on red horse chestnut in the field. Female third instar nymphs were noticed between 9. September and 28. April and fourth instar adult females from 31. March on.In the laboratoryP. regalis individuals on horse chestnut and sycamore maple did only growth at 18°C and fluctuating temperature of 20/14°C (16/8 h). The growth was heavily affected at warm temperatures of 26°C and scale insects lived only a few weeks. Only at the fluctuating temperature of 20/14°C (16/8 h) some females laid eggs on horse chestnut and sycamore maple from the 49. and 48. week on.

---

Untersuchungen über Entwicklungsstadien der Wolligen NapfschildlausPulvinaria regalis Canard (Hom., Coccidae) im Freiland und Labor

Zusammenfassung In der vorliegenden Arbeit wurden die Entwicklungsstadien der Wolligen NapfschildlausPulvinaria regalis Canard im Freiland an einer Rotblütigen Roßkastanie (Aesculus x carnea) im Stadtgebiet von Bonn, sowie das Körperwachstum an Bergahorn (Acer pseudoplatanus) und Roßkastanie (Aesculus hippocastanum) bei unterschiedlichen Temperatubedingungen im Labor untersucht.Die Freilandpopulation zeigte von Juli bis Anfang Dezember eine geringe lineare, von Mitte Dezember bis Anfang März nahezu keine und von Mitte März bis Anfang Mai eine exponentielle Zunahme der durchschnittlichen Körperlänge. Durch das Aufstellen einer Häufigkeitsverteilung der Analplattenlänge sowie durch das gleichzeitige Messen von neuen und noch nicht abgestreiften alten Analplatten während der Häutungsphase konnte ein Maß zur Abgrenzung der Entwicklungsstadien ermittelt werden. Die Analplattenlänge von Crawlern/Settlern (=erstes Larvenstadium) lagen im Bereich von 0,030–0,054 mm, des ersten und zweiten Nymphenstadiums im Bereich von 0,066–0,900 mm und 0,102–0,150 mm. Bei adulten Weibchen lag die Analplattenlänge zwischen 0,162 und 0,246 mm und bei männlichen Präpuppen zwischen 0,075 und 0,098 mm. Da die Cuticula vonP. regalis sehr dehnbar ist, war eine sichere Stadienzuordnung nur mit Hilfe der stark sklerotisierten Analplatte möglich. Bis zum 12. August waren Crawler/Settler und bis zum 29. September Erstnymphen zu beobachten. Weibliche Zweitnymphen traten vom 9. September bis 28. April und adulte Weibchen ab dem 31. März in Erscheinung.Im Labor konnte auf den Versuchspflanzen Roßkastanie und Bergahorn ein Wachstum der Körperlänge vonP. regalis-Individuen bei Konstanttemperatur von 18°C und bei Wechseltemperatur von 20/14°C (16/8 h) gemessen werden. Bei einer Konstanttemperatur von 26°C war das Wachstum auf beiden Wirtspflanzenarten gestört und ein Überleben nur für wenige Wochen möglich. Nur in der Temperaturvariante 20/14°C (16/8 h) legten einige Weibchen ab der 49. Woche auf Roßkastanie und ab der 48. Woche auf Bergahorn Eier ab.

---

---

With 2 tables and 4 figures

---

Dedicated to Prof. Dr.W. Schwenke for 75th birthday 22.3.1996.  相似文献   

Adrenal insufficiency secondary to lymphocytic panhypophysitis in a cat          下载免费PDF全文

AJ Rudinsky  ES Clark  DS Russell  C Gilor 《Australian veterinary journal》2015,93(9):327-331

  相似文献   

Endogenous Progesterone Concentrations Affect Progesterone Release from Intravaginal Devices Used for Oestrous Synchronization in Cattle          下载免费PDF全文

HL Neri  MP Palhao  DS Costa  JHM Viana  CAC Fernandes 《Reproduction in domestic animals》2015,50(4):692-695

Intravaginal progesterone‐releasing devices are largely used both as contraceptives in humans and as a component of oestrous synchronization protocols in cattle. To reduce costs in large‐scale timed artificial insemination, the reuse of these releasing devices is common. Passive hormone diffusion, however, depends on the concentration gradient, which could affect the amount of residual progesterone present in these devices after a first use. To evaluate the effect of the presence of a corpus luteum in the release of progesterone from intravaginal devices, three synchronization protocols were designed to simulate the effects of inserting the device in the early dioestrus, late dioestrus or anoestrus. Holstein‐Zebu cross‐bred heifers were randomly allocated into one of these three treatments, and a series of blood samples was taken to evaluate the plasma progesterone concentrations. After 8 days, the intravaginal devices were removed and underwent a previously validated alcoholic extraction technique to measure the residual progesterone. Non‐used devices were used as controls. As expected, the simultaneous presence of the intravaginal device and a corpus luteum resulted in increased plasma progesterone concentrations. Conversely, the amount of residual progesterone in the devices after use was inversely proportional to the plasma progesterone concentration. These results demonstrate that the release rate of progesterone from intravaginal devices is affected by the endogenous concentration of this hormone; consequently, the strategy for reuse should account for the category and expected luteal cyclic activity of the animals undergoing synchronization protocols.  相似文献   

Earthworm activity as a determinant for N₂O emission from crop residue     

Elena Rizhiya  Chiara Bertora  Petra C.J. van Vliet  Jack H. Faber 《Soil biology & biochemistry》2007,39(8):2058-2069

Earthworm activity may have an effect on nitrous oxide (N₂O) emissions from crop residue. However, the importance of this effect and its main controlling variables are largely unknown. The main objective of this study was to determine under which conditions and to what extent earthworm activity impacts N₂O emissions from grass residue. For this purpose we initiated a 90-day (experiment I) and a 50-day (experiment II) laboratory mesocosm experiment using a Typic Fluvaquent pasture soil with silt loam texture. In all treatments, residue was applied, and emissions of N₂O and carbon dioxide (CO₂) were measured. In experiment I the residue was applied on top of the soil surface and we tested (a) the effects of the anecic earthworm species Aporrectodea longa (Ude) vs. the epigeic species Lumbricus rubellus (Hoffmeister) and (b) interactions between earthworm activity and bulk density (1.06 vs. 1.61 g cm⁻³). In experiment II we tested the effect of L. rubellus after residue was artificially incorporated in the soil. In experiment I, N₂O emissions in the presence of earthworms significantly increased from 55.7 to 789.1 μg N₂O-N kg⁻¹ soil (L. rubellus; p<0.001) or to 227.2 μg N₂O-N kg⁻¹ soil (A. longa; p<0.05). This effect was not dependent on bulk density. However, if the residue was incorporated into the soil (experiment II) the earthworm effect disappeared and emissions were higher (1064.2 μg N₂O-N kg⁻¹ soil). At the end of the experiment and after removal of earthworms, a drying/wetting and freezing/thawing cycle resulted in significantly higher emissions of N₂O and CO₂ from soil with prior presence of L. rubellus. Soil with prior presence of L. rubellus also had higher potential denitrification. We conclude that the main effect of earthworm activity on N₂O emissions is through mixing residue into the soil, switching residue decomposition from an aerobic and low denitrification pathway to one with significant denitrification and N₂O production. Furthermore, A. longa activity resulted in more stable soil organic matter than L. rubellus.  相似文献   

PATHWAY OF INVASION IN A CYNOMOLGUS MONKEY AFTER ORAL APPLICATION OF POLIOMYELITIS VIRUS     

Faber HK  Silverberg RJ 《Science (New York, N.Y.)》1942,96(2499):473-475

  相似文献   

A free-fall determination of the newtonian constant of gravity     

JP Schwarz  DS Robertson  TM Niebauer  JE Faller 《Science (New York, N.Y.)》1998,282(5397):2230-2234

Recent determinations of the Newtonian constant of gravity have produced values that differ by nearly 40 times their individual error estimates (more than 0.5%). In an attempt to help resolve this situation, an experiment that uses the gravity field of a one-half metric ton source mass to perturb the trajectory of a free-falling mass and laser interferometry to track the falling object was performed. This experiment does not suspend the test mass from a support system. It is therefore free of many systematic errors associated with supports. The measured value was G = (6.6873 +/- 0. 0094) x 10(-11) m3 kg-1 sec-2.  相似文献   

In situ measurements of organics, meteoritic material, mercury, and other elements in aerosols at 5 to 19 kilometers   总被引：1，自引：0，他引：1  

DM Murphy  DS Thomson  MJ Mahoney 《Science (New York, N.Y.)》1998,282(5394):1664-1669

In situ measurements of the chemical composition of individual aerosol particles at altitudes between 5 and 19 kilometers reveal that upper tropospheric aerosols often contained more organic material than sulfate. Although stratospheric aerosols primarily consisted of sulfuric acid and water, many also contained meteoritic material. Just above the tropopause, small amounts of mercury were found in over half of the aerosol particles that were analyzed. Overall, there was tremendous variety in aerosol composition. One measure of this diversity is that at least 45 elements were detected in aerosol particles. These results have wide implications for the complexity of aerosol sources and chemistry. They also offer possibilities for understanding the transport of atmospheric aerosols.  相似文献   

Biodiversity effects on soil processes explained by interspecific functional dissimilarity     

Heemsbergen DA  Berg MP  Loreau M  van Hal JR  Faber JH  Verhoef HA 《Science (New York, N.Y.)》2004,306(5698):1019-1020

The loss of biodiversity can have significant impacts on ecosystem functioning, but the mechanisms involved lack empirical confirmation. Using soil microcosms, we show experimentally that functional dissimilarity among detritivorous species, not species number, drives community compositional effects on leaf litter mass loss and soil respiration, two key soil ecosystem processes. These experiments confirm theoretical predictions that biodiversity effects on ecosystem functioning can be predicted by the degree of functional differences among species.  相似文献   

Quantitative morphological studies on various organs of the MINI-LEWE miniature swine]     

R Berg  G Gregor  D Faber 《Archiv fuer experimentelle veterinaermedizin》1976,30(6):823-834

Quantitative morphological studies were conducted into 27 MINI-LEWE miniature pigs, with the view to exploring the correlations between a number of organs (liver, kidneys, heart, spleen, pancreas, adrenal gland, and thyroid gland) and parameters (live weight, age, weight at slaughter, length from snout to tail root, and internal length of slaughter body). The results are presented in 12 ilustrations and five tables.  相似文献