Boron: possible role in plant metabolism     

Rajaratnam JA  Lowry JB  Avadhani PN  Corley RH 《Science (New York, N.Y.)》1971,172(3988):1142-1143

Leaves of boron-deficient oil palm showed a total absence of the leucoanthocyanins usually present, well before onset of pathological symptoms. The association of boron with flavonoid synthesis is consistent with the otherwise anomalous situation that this element is essential for higher plants but not for animals or lower plants.  相似文献   

Genetic adaptation of White Leghorn hens to life in single cages     

D C Lowry  H Abplanalp 《British poultry science》1970,11(1):117-131

Specific adaptations of selected lines to their conditions of management were found for egg production, but not for several other traits, when hens of different selection histories were tested under both conditions. Floor selected sublines were superior to cage selected sublines in floor pens but inferior when both were tested in individual cages. The study involved three populations of two sublines in each of which selection for egg production had been practised over seven generations. Under one management birds from the three populations were intermingled in large floor pens; under the other, among individual cages.

The role of social dominance as expressed in competition for food was explored. Floor selected hens were the more dominant in floor pens as well as in paired tests in cages.  相似文献   

Climatology     

Lowry WP 《Science (New York, N.Y.)》1982,215(4531):391

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Entrainment and impingement of juvenile silver perch,Bidyanus bidyanus,and golden perch,Macquaria ambigua,at a fish screen: effect of velocity and light     

C. A. Boys  L. J. Baumgartner  M. Lowry 《Fisheries Management and Ecology》2013,20(4):362-373

Entrainment and impingement of two non‐salmonid species susceptible to entrainment at irrigation diversions, silver perch, Bidyanus bidyanus (Mitchell), and golden perch, Macquaria ambigua (Richardson), were examined at an experimental intake screen in a laboratory flume under a range of velocities and light levels. The presence of an intake screen significantly reduced entrainment, in some cases reducing mortality from over 90% (unscreened) to less than 2% (when screened). Although some differences in behaviour existed between species, approach velocities (measured 8 cm in front of the screen) up to 0.4 m s^?1 effectively reduced entrainment, with very little injury or mortality resulting from incidental screen contacts or impingement. Both species used visual cues to negotiate the screen face, thereby increasing their ability to avoid contact at higher velocities. In the absence of these visual cues, positive rheotactic behaviour was enhanced and fish mostly avoided approaching the screen. These results demonstrate that fish screens operated at approach velocities of up to 0.4 m s^?1 have great potential for the protection of silver perch and golden perch juveniles at irrigation intakes.  相似文献   

Effects of sodium chloride on selected parameters in cats     

Kirk CA  Jewell DE  Lowry SR 《Veterinary therapeutics : research in applied veterinary medicine》2006,7(4):333-346

This study used 36 cats with varying renal insufficiency and physiologic status to evaluate the effect of a food high in sodium chloride (HSC) compared with a low sodium chloride (LSC) food on selected blood parameters and blood pressure. Cats eating the HSC food had an increase in serum creatinine, urea nitrogen, and phosphorus compared with cats eating the LSC food. Also, cats eating the HSC food had increased fractional excretion of calcium and increased fractional shortening during cardiac contraction. There was no effect of food on systolic, diastolic, or mean arterial pressure.  相似文献   

Long-term transmission of defective RNA viruses in humans and Aedes mosquitoes     

Aaskov J  Buzacott K  Thu HM  Lowry K  Holmes EC 《Science (New York, N.Y.)》2006,311(5758):236-238

In 2001, dengue virus type 1 (DENV-1) populations in humans and mosquitoes from Myanmar acquired a stop-codon mutation in the surface envelope (E) protein gene. Within a year, this stop-codon strain had spread to all individuals sampled. The presence of truncated E protein species within individual viral populations, along with a general relaxation in selective constraint, indicated that the stop-codon strain represents a defective lineage of DENV-1. We propose that such long-term transmission of defective RNA viruses in nature was achieved through complementation by coinfection of host cells with functional viruses.  相似文献   

Can animals help earthquake predictors?     

Lowry MA 《New Zealand veterinary journal》1983,31(3):35-39

Most great earthquakes leave in their wake stories of unusual animal behaviour that preceded the main event, often by an interval long enough to be useful for warning purposes. Although much of this reported behaviour has perhaps been classified as unusual only with the benefit of hindsight, a residue of convincing stories remains and it does seem possible that animals sometimes respond to certain geophysical changes associated with the approach of rock failure, that are not monitored by instruments. Anomalous animal behaviour is difficult to interpret, because it may arise from various causes. But this is a defect shared with other short-term precursors of great earthquakes, so study of the subject as a possible part of an imminent danger warning scheme should not be neglected on that ground alone. Mankind;s past success in exploiting animal sensitivities, even before learning to understand them fully, encourages the hope that useful results will emerge.  相似文献   

Managing the development of artificial reef systems: The need for quantitative goals          下载免费PDF全文

Alistair Becker  Matthew D. Taylor  Heath Folpp  Michael B. Lowry 《Fish and Fisheries》2018,19(4):740-752

Fisheries enhancement initiatives are a potentially useful tool for managers to supplement traditional approaches. Habitat‐based enhancements often deploy artificial reefs with the aim to increase the available structure to augment local production, yet current assessment approaches make it difficult to assess whether these reefs achieve pre‐deployment goals. This makes it hard for managers to determine whether artificial reefs could improve their fishery outputs, potentially leading to missed opportunities and reduced production. We reviewed 270 research articles to determine whether existing monitoring studies identify whether artificial reefs meet their pre‐deployment goals, thereby providing some evidence of their suitability for certain fisheries. We found only 62% of these studies clearly articulated the original goals of the reef. Goals were qualitative, and most studies were conducted over insufficient time frames to allow for ecological communities to stabilize and mature. It is therefore difficult to determine the success or failure of many artificial reefs in addressing the management issues for which they were deployed. In the light of these findings, we think the setting of explicit quantitative goals (which may be biological, social or economic), and monitoring the performance of reefs against these goals, could stimulate the broader application of artificial reefs in fisheries management strategies. Such an approach has been successfully adopted in aquaculture‐based fisheries enhancement, and we explain how current evaluation methods such as harvest strategies can be easily adapted to quantitatively monitor artificial reef performance.  相似文献   

Amelioration of selenium toxicity by arsenicals and cysteine     

K R Lowry  D H Baker 《Journal of animal science》1989,67(4):959-965

Young chicks exhibited a 61% reduction in weight gain when a corn-soybean meal diet was supplemented with 15 mg/kg Se provided as Na selenite. The same level of Se provided as selenomethionine depressed weight gain by 32%. Supplementing the high selenite diet with isoarsenous (14 mg/kg As) additions of As2O5, As2O3, phenylarsonic acid, phenylarsine oxide and roxarsone ameliorated the Se-induced growth depression: As2O5 almost totally restored growth rate; As2O3, phenylarsonic acid and phenylarsine oxide gave intermediate responses; and roxarsone gave only a small ameliorative growth response. Arsanilic acid was without effect in stimulating growth rate of selenite-intoxicated chicks. Dietary addition of .4% L-cysteine produced a growth response in selenite intoxicated chicks that was somewhat greater than that obtained with roxarsone; administering both roxarsone and cysteine corrected growth better than either compound given singly. Both roxarsone and As2O5 also effectively ameliorated the Se-toxicity growth depression caused by selenomethionine (15 mg Se/kg) supplementation, but cysteine showed no efficacy against morbidity caused by this form of Se. Liver Se concentration was elevated 10-fold by selenite and 25-fold by selenomethionine supplementation. The arsenic compounds had varying effects on liver Se, whereas cysteine tended to increase Se concentration. These findings suggest that both inorganic and organic arsenicals as well as cysteine ameliorate selenium toxicity by different mechanisms.  相似文献   

Voluntary intake and ingestive behavior of steers grazing Johnstone or endophyte-infected Kentucky-31 tall fescue.     

M D Howard  R B Muntifering  N W Bradley  G E Mitchell  S R Lowry 《Journal of animal science》1992,70(4):1227-1237

Effects of grazing low-endophyte (Acremonium coenophialum Morgan-Jones and Gams, less than 1% infection) Johnstone (J) or high-endophyte (60% infection) Kentucky-31 (K) tall fescue (Festuca arundinacea Schreb.) on grazing behavior and voluntary intake were studied. Six Angus steers (average initial BW = 326 kg) grazed 1.21-ha plots of each forage cultivar (three steers per cultivar) in four 28-d periods beginning May 27. Daytime observations (0630 until 2130) revealed that J steers spent more (P less than .10) time grazing and lying down and took more (P less than .05) prehensile bites than K steers did; conversely, steers grazing K spent more (P less than .10) time standing and idling than J steers did. Idling time showed a forage x period interaction (P less than .10). Mean OM bite size (grams per bite) was not affected (P greater than .10) by forage but differed (P less than .10) among periods. Limited nighttime observations (2130 until 0630) revealed no effects (P greater than .10) of forage on grazing time or number of prehensile bites taken. Voluntary intakes of OM and NDF did not differ (P greater than .10) between steers grazing J and K; however, a forage x period interaction (P less than .10) existed such that, during Period 1, steers grazing J had greater (P less than .01) OM and NDF intakes than did steers grazing K. These data suggest that cattle grazing endophyte-infected tall fescue display altered daytime grazing behavior and that reduction of voluntary intake attributable to endophyte infection may be less severe under free-grazing than has been reported for controlled environmental conditions.  相似文献