Livestock grazing has minimal effect on the species richness and diversity of semi-arid shrubland in the Western Little Karoo,South Africa     

Nelmarie Saayman  Craig Morris  Hannes Botha 《African Journal of Range and Forage Science》2016,33(4):225-233

The Succulent Karoo, one of two arid biodiversity hotspots in the world, is known for its high plant species richness, but little is known about the influence of topography and how it mediates the potentially deleterious effects of grazing. Changes in vegetation species composition, cover and species diversity were examined along piosphere gradients on northerly slopes, bottomlands and low-lying plains on 45 farms. Landscapes differed in the plant speciesand life-form composition, species richness and cover, with the more species-rich, heterogeneous grassy northerly slopes distinct from the plains and bottomlands, which were dominated by Pteronia pallens, Psilocaulon junceum and Drosanthenum spp. with more annual and ephemeral species. Overall, species richness declined linearly with decreasing rangeland condition. A weak grazing effect was detected only on the north-facing slopes, where shrubs and grass decreased with intense grazing. Years of overgrazing have resulted in the widespread dominance of P. pallens, especially on the plains and bottomlands, rendering them insensitive to grazing. The current condition of the northern slopes should be maintained and managed such that palatable species can spread to more degraded areas of the landscape.  相似文献   

Performance of light vs heavy steers grazing Plains Old World bluestem at three stocking rates   总被引：1，自引：0，他引：1  

Ackerman CJ  Purvis HT  Horn GW  Paisley SI  Reuter RR  Bodine TN 《Journal of animal science》2001,79(2):493-499

Live weight gains of light and heavy calves grazing Plains Old World bluestem at three stocking rates were evaluated during the summers of 1997 and 1998. Initial weights of mixed-breed light-weight steers (LHT) were 141 SD = 17 kg (n = 214) in 1997 and 160 SD = 23 kg (n = 193) in 1998. Initial weights of mixed-breed heavy steers (HWT) were 265 SD = 17 kg (n = 115) in 1997 and 248 SD = 13 kg (n = 126) in 1998. Initial stocking rates for both sizes of steers were as follows: light, 392 kg of live weight/ha; moderate, 504 kg of live weight/ha (increased to 616 kg live weight/ha in 1998); and heavy, 840 kg of live weight/ ha. Averaged gain and gain/hectare are reported as stocking rate by steer type within year. Heavy steers had greater ADG than LHT steers during both years. Forage intake, expressed as a percentage of BW, was greater (P = 0.05) for LHT (3.1%) than for HWT (2.8%) calves. Grazing time (min/d; 1998 only) was greater (P = 0.05) for LHT (665) than for HWT (624) steers. Forage CP and in vivo digestible organic matter (DOM) were slightly greater (P < 0.05) in pastures grazed by HWT vs LHT cattle. Gain/hectare was greater (P < 0.05) for LHT than for HWT calves at all three stocking rates during both years. A linear decline in ADG was observed (P < 0.07) as stocking rates increased for HWT steers in 1997 and LHT steers in 1998. However, ADG did not decline with increasing stocking rate for LHT calves during 1997 or HWT calves during 1998. Forage intake was not different among stocking rates in either 1997 or 1998. Grazing time was greatest (P < 0.05) for steers in the moderate and heavy stocking rates. Forage in vivo DOM decreased (P < 0.05) as stocking rate increased. Both LHT and HWT steers had lower (P < 0.05) ADG at all three stocking rates during 1998 compared with 1997. Despite lower ADG, LHT steers had greater gain/hectare than HWT steers during both 1997 and 1998.  相似文献   

Dellmann's Textbook of Veterinary Histology. 6th edition - Edited by Eurell J, Frappier BL     

R Reuter 《Australian veterinary journal》2007,85(8):310-310

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Die Salemer Lärche im Bodenseegebiet     

Hannes Mayer 《European Journal of Forest Research》1964,83(11-12):321-350

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III. Buchbesprechungen     

A. Baumgartner  Hannes Mayer 《European Journal of Forest Research》1964,83(7-8):255-256

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Zur Übertragbarkeit waldbaulicher Folgerungen in vergleichbaren tannenreichen Waldgesellschaften (Abieti-Fagetum und Abietetum) der nördlichen West- und Ostalpen     

Hannes Mayer 《European Journal of Forest Research》1964,83(1-2):38-63

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III. Buchbesprechungen     

Speer  Hannes Mayer  Abetz 《European Journal of Forest Research》1958,77(3-4):126-128

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III. Buchbesprechungen     

Mägdefrau  E. Rohmeder  A. Baumgartner  Hannes Mayer 《European Journal of Forest Research》1957,76(11-12):382-384

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Prof. Dipl. Ing. Dr. Dr. h. c. Leo Tschermak zum Gedenken     

Hannes Mayer 《European Journal of Forest Research》1969,88(1):378-379

Ohne Zusammenfassung  相似文献   

Breed Differences in Natriuretic Peptides in Healthy Dogs     

K. Sjstrand  G. Wess  I. Ljungvall  J. Hggstrm  A‐C. Merveille  M. Wiberg  V. Gouni  J. Lundgren Willesen  S. Hans  A‐S. Lequarr  L. Mejer Srensen  J. Wolf  L. Tiret  M. Kierczak  S. Forsberg  K. McEntee  G. Battaille  E. Seppl  K. Lindblad‐Toh  M. Georges  Hannes Lohi  V. Chetboul  M. Fredholm  K. Hglund 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):451-457

Background

Measurement of plasma concentration of natriuretic peptides (NPs) is suggested to be of value in diagnosis of cardiac disease in dogs, but many factors other than cardiac status may influence their concentrations. Dog breed potentially is 1 such factor.

Objective

To investigate breed variation in plasma concentrations of pro‐atrial natriuretic peptide 31‐67 (proANP 31‐67) and N‐terminal B‐type natriuretic peptide (NT‐proBNP) in healthy dogs.

Animals

535 healthy, privately owned dogs of 9 breeds were examined at 5 centers as part of the European Union (EU) LUPA project.

Methods

Absence of cardiovascular disease or other clinically relevant organ‐related or systemic disease was ensured by thorough clinical investigation. Plasma concentrations of proANP 31‐67 and NT‐proBNP were measured by commercially available ELISA assays.

Results

Overall significant breed differences were found in proANP 31‐67 (P < .0001) and NT‐proBNP (P < .0001) concentrations. Pair‐wise comparisons between breeds differed in approximately 50% of comparisons for proANP 31‐67 as well as NT‐proBNP concentrations, both when including all centers and within each center. Interquartile range was large for many breeds, especially for NT‐proBNP. Among included breeds, Labrador Retrievers and Newfoundlands had highest median NT‐proBNP concentrations with concentrations 3 times as high as those of Dachshunds. German Shepherds and Cavalier King Charles Spaniels had the highest median proANP 31‐67 concentrations, twice the median concentration in Doberman Pinschers.

Conclusions and Clinical Importance

Considerable interbreed variation in plasma NP concentrations was found in healthy dogs. Intrabreed variation was large in several breeds, especially for NT‐proBNP. Additional studies are needed to establish breed‐specific reference ranges.  相似文献