Ergovaline does not alter the severity of ryegrass staggers induced by lolitrem B     

SC Finch  JB Vlaming  BL Sutherland  C van Koten  WJ Mace  LR Fletcher 《New Zealand veterinary journal》2018,66(2):93-97

AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline.

METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.

RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).

CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.  相似文献   

Effect of Stocking Density on Growth,Survival, and Condition of the Mexican Cichlid Cichlasoma beani     

Edgar A. Aragon‐Flores  Edna F. Valdez‐Hernandez  Leonardo Martinez‐Cardenas  Maria R. Castaeda‐Chavez  Alfonso A. Gonzales‐Diaz  Miriam Soria‐Barreto  Javier M. J. Ruiz‐Velazco  Emilio Pea‐Messina 《Journal of the World Aquaculture Society》2014,45(4):447-453

The Mexican cichlid Cichlasoma beani is currently exploited regionally as food and can be commercialized in the aquarium trade. Natural populations of C. beani may already be negatively affected by anthropogenic alteration of the areas in which it is distributed. The aim of the present study was to examine the effect on growth, survival, and condition of C. beani cultured in three stocking densities: three (D3), six (D6), and nine (D9) fish per each 40 L tank. At the end of a 6‐wk trial the fish cultured in D3 were longer, heavier, and grew faster than the rest of the treatments but their survival was the lowest compared to D6 and D9. The mortalities were caused by a strong aggressive behavior in D3.  相似文献   

Use of stem diameter variations to detect plant water stress in tomato   总被引：3，自引：0，他引：3  

M. Gallardo  R. B. Thompson  L. C. Valdez  M. D. Fernández 《Irrigation Science》2006,24(4):241-255

The sensitivity of stem diameter variations (SDV) measured with linear variable transducer (LVDT) sensors as indicators of plant water status in tomato was evaluated. Two tomato crops were grown sequentially in a sandy loam soil in an unheated plastic greenhouse. These were an autumn–winter tomato crop (autumn crop) and a spring–summer tomato crop (spring crop). One drying cycle of 61 days was imposed to the autumn crop in winter at 92 days after transplanting (DAT). Two drying cycles, each of 29 days, were applied to the spring crop, to young (58 DAT) and mature plants (121 DAT). For each drying cycle, four replicate plots did not receive irrigation, and four were well watered. During each drying cycle, LVDT sensors continuously measured SDV, and daily measurements were made of leaf (Ψ _leaf) and stem water potential (Ψ _stem). SDV data was interpreted using the SDV-derived indices, maximum daily shrinkage (MDS) and stem growth rate (SGR). The response of SDV-derived indices to water deficit differed with (1) climatic conditions during stress imposition and (2) crop age. In the winter drying cycle of the autumn crop, the responses of the SDV-derived indices to soil drying were relatively small and slower than Ψ _leaf and Ψ _stem. Under warmer conditions, the SDV-derived indices were much more responsive to soil drying. In rapidly growing young plants, where SDV was characterized by high SGR and small MDS, SGR was the most sensitive SDV-derived index. In more mature plants with little stem growth, MDS was the most sensitive SDV-derived index. In mature plants grown in warm to hot conditions, MDS (1) responded at a similar time or earlier than Ψ _leaf and Ψ _stem and (2) had larger “signal” values (ratio of values from unwatered to control plants) than Ψ _leaf and Ψ _stem. However, there was appreciably more “noise” (coefficient of variation, CV) associated with the SDV-derived indices, giving lower “sensitivity” values, determined from “signal” to “noise” ratios, than for Ψ _leaf and Ψ _stem. Regression analysis between MDS of well-watered plants and climatic variables gave best results for a linear relationship between MDS and daily maximum vapor pressure deficit. There were strong linear relationships between MDS and Ψ _leaf for each drying cycle. The slopes of these relationships differed with crop age indicating that there was no constant relationship between MDS and Ψ _leaf for a whole season. Overall these results demonstrated that MDS and SGR can be sensitive indicators of the water status of tomato crops under conditions of moderate to high evaporative demand. However, the variability associated with the SDV-derived indices and the changing MDS–Ψ _leaf relationship with crop age represent major issues regarding the development of irrigation scheduling protocols for tomato.  相似文献   

POST-PARTURIENT HAEMOGLOBINURIA OF DAIRY COWS     

B. Parkinson  B.V.Sc. A. K. Sutherland  B.V.SC  M.S. 《Australian veterinary journal》1954,30(8):232-236

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SEROLOGICAL DIAGNOSIS OF LARVAL CESTODES IN SHEEP     

Sally K.  Blundell-Hasell M.SC. 《Australian veterinary journal》1969,45(7):334-336

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THE BOVINE MUCOSAL DISEASE-SWINE FEVER VIRUS COMPLEX IN PIGS   总被引：2，自引：0，他引：2  

W. A. Snowdon  B.V.SC. E. L. French  M.SC  Ph.D. 《Australian veterinary journal》1968,44(4):179-184

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STUDIES ON THE TRANSMISSIBILITY OF A VIRAL MENINGO-ENCEPHALITIS OF CALVES     

L. A. Y. Johnston  B.V.SC.  G. C. Simmons  B.SC. M. D. McGavin  M.V.SC. 《Australian veterinary journal》1964,40(5):189-194

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HYDATID DISEASE IN AUSTRALIA     

Michael A.  Gemmell B.V.SC. P. Brydon  B.V.SC. 《Australian veterinary journal》1960,36(3):73-78

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CHEMOTHERAPY OF CAECA L COCCIDIOSIS IN CHICKENS     

J. H. Arundel  B.V.SC  A.M.T.C. 《Australian veterinary journal》1960,36(2):49-53

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Isolation of oral spirochetes from dogs and cats and provisional identification using polymerase chain reaction (PCR) analysis specific for human plaque Treponema spp     

Valdez M  Haines R  Riviere KH  Riviere GR  Thomas DD 《Journal of veterinary dentistry》2000,17(1):23-26

Identification of plaque spirochetes from dogs is rare and no studies to date report cultivation of canine or feline plaque spirochetes. Plaque samples obtained from canine and feline patients were cultured in broth media. Spirochetes cultured were subjected to microscopic evaluation and were cloned on a solid medium. The clones were provisionally identified using species-specific PCR for treponema isolated from human plaque. Canine spirochete clones included Treponema denticola, T. socranskii ssp., T. vincentii, T. maltophilum, T. medium, and T. pectinovorum. Feline clones included T. maltophilum and T. socranskii. Non-amplified clones may represent novel treponemes. Future studies will be aimed at comparison of the spirochetes present in dogs and cats with or without periodontal disease.  相似文献