This article addresses the minimum data base needed to assist the clinician's diagnostic approach to neurologic diseases. The collection, storage, and processing of cerebrospinal fluid samples are ...discussed. Additional diagnostic tests are described under selected specific etiologies.
Assessment of the nervous system Holbrook, T C; White, S L
The Veterinary clinics of North America. Food animal practice,
07/1992, Letnik:
8, Številka:
2
Journal Article
Recenzirano
This article describes the examination of the neurologic and ophthalmic systems in ruminants. Neuroanatomy with respect to lesion localization is reviewed. Pertinent age and species differences are ...addressed. The practical aspects of assessing the neurologic system are stressed, and the reader is directed to other sources of information for assistance in determining the differential diagnosis and therapy of neurologic disease.
Background Advances in acoustic telemetry technology have led to an improved understanding of the spatial ecology of many freshwater and marine fish species. Understanding the performance of acoustic ...receivers is necessary to distinguish between tagged fish that may have been present but not detected and from those fish that were absent from the area. In this study, two stationary acoustic transmitters were deployed 250 m apart within each of four acoustic receiver lines each containing at least 10 receivers (i.e., eight acoustic transmitters) located in Saginaw Bay and central Lake Huron for nearly 2 years to determine whether the probability of detecting an acoustic transmission varied as a function of time (i.e., season), location, and distance between acoustic transmitter and receiver. Distances between acoustic transmitters and receivers ranged from 200 m to >10 km in each line. The daily observed probability of detecting an acoustic transmission was used in simulation models to estimate the probability of detecting a moving acoustic transmitter on a line of receivers. Results The probability of detecting an acoustic transmitter on a receiver 1000 m away differed by month for different receiver lines in Lake Huron and Saginaw Bay but was similar for paired acoustic transmitters deployed 250 m apart within the same line. Mean probability of detecting an acoustic transmitter at 1000 m calculated over the study period varied among acoustic transmitters 250 m apart within a line and differed among receiver lines in Lake Huron and Saginaw Bay. The simulated probability of detecting a moving acoustic transmitter on a receiver line was characterized by short periods of time with decreased detection. Although increased receiver spacing and higher fish movement rates decreased simulated detection probability, the location of the simulated receiver line in Lake Huron had the strongest effect on simulated detection probability. Conclusions Performance of receiver lines in Lake Huron varied across a range of spatiotemporal scales and was inconsistent among receiver lines. Our simulations indicated that if 69 kHz acoustic transmitters operating at 158 dB in 10-30 m of freshwater were being used, then receivers should be placed 1000 m apart to ensure that all fish moving at 1 m s-1 or less will be detected 90% of days over a 2-year period. Whereas these results can be used as general guidelines for designing new studies, the irregular variation in acoustic transmitter detection probabilities we observed among receiver line locations in Lake Huron makes designing receiver lines in similar systems challenging and emphasizes the need to conduct post hoc analyses of acoustic transmitter detection probabilities.
Screening of peanut germ plasm for resistance to Tomato spotted wilt virus (TSWV) has been largely inefficient due to the lack of a screening technique based on mechanical transmission of the virus ...under controlled environmental conditions. We have studied the reaction of three peanut cultivars (Georgia Green, Georgia Runner, C-99R) and one breeding line (C11-2-39) using a highly efficient mechanical inoculation procedure. The disease response was studied at two temperature regimes, 25 to 30°C (low temperature) and 30 to 37°C (high temperature). Based on percent transmission, symptomatology, distribution of TSWV, and relative levels of TSWV nucleocapsid (N) protein, Georgia Runner and Georgia Green were found to be susceptible, whereas C-99R and C11-2-39 were resistant. Of the four genotypes tested, C11-2-39 had the highest level of resistance to TSWV. The results correlated with the field performance of the genotypes except in the case of Georgia Green, which could not be distinguished from TSWV-susceptible Georgia Runner. Exposure of the inoculated plants to higher temperature (30 to 37°C) resulted in a better resistant response as reflected by reduced systemic infection, localized symptom expression, restricted viral movement, and reduced levels of TSWV antigen. To our knowledge, this is the first report of differential response of peanut genotypes to TSWV using mechanical inoculation. The four peanut genotypes should be useful as reference standards for the initial screening and identification of sources of TSWV resistance in peanut germ plasm.
To determine the depletion of muscle glycogen during five consecutive days of endurance exercise in Alaskan sled dogs consuming a high-fat, low-carbohydrate diet.
Forty-two fit Alaskan sled dogs were ...used in the study, of which six dogs served as nonexercising control animals. The remaining 36 dogs ran 160 km x d(-1) for up to 5 d while consuming a diet providing approximately 50% of calories as fat and 15% as carbohydrate. Muscle biopsies were performed on six randomly selected dogs before feeding and within 4 h after each 160-km run was completed. Muscle samples were prepared for analysis of glycogen content and myosin ATPase staining. Serum creatine kinase (CK) activity was measured once before exercise and after each 160-km run.
Thirty-three of 36 dogs completed the runs. Muscle glycogen concentration was highest in sedentary dogs (340 +/- 102 mmol x kg(-1) dry weight), declined to 73 +/- 16 after 160 km and subsequently increased to similar levels between 320 and 800 km (320 km: 177 +/- 34; 800 km: 213 +/- 44). Postexercise serum CK activity was significantly elevated throughout the study.
Skeletal muscle in Alaskan sled dogs has remarkable glyconeogenic ability as demonstrated by repletion to greater than 50% of resting muscle glycogen concentrations after the second of five consecutive 160-km runs even when fed a low-carbohydrate, high-fat diet. Whether this finding is attributable to rapid repletion of muscle glycogen during brief recovery periods versus progressive utilization of alternative substrates remains to be investigated.
Fish migration in large freshwater lacustrine systems such as the Laurentian Great Lakes is not well understood. The walleye (Sander vitreus) is an economically and ecologically important native fish ...species throughout the Great Lakes. In Lake Huron walleye has recently undergone a population expansion as a result of recovery of the primary stock, stemming from changing food web dynamics. During 2011 and 2012, we used acoustic telemetry to document the timing and spatial scale of walleye migration in Lake Huron and Saginaw Bay. Spawning walleye (n = 199) collected from a tributary of Saginaw Bay were implanted with acoustic tags and their migrations were documented using acoustic receivers (n = 140) deployed throughout U.S. nearshore waters of Lake Huron. Three migration pathways were described using multistate mark-recapture models. Models were evaluated using the Akaike Information Criterion. Fish sex did not influence migratory behavior but did affect migration rate and walleye were detected on all acoustic receiver lines. Most (95%) tagged fish migrated downstream from the riverine tagging and release location to Saginaw Bay, and 37% of these fish emigrated from Saginaw Bay into Lake Huron. Remarkably, 8% of walleye that emigrated from Saginaw Bay were detected at the acoustic receiver line located farthest from the release location more than 350 km away. Most (64%) walleye returned to the Saginaw River in 2012, presumably for spawning. Our findings reveal that fish from this stock use virtually the entirety of U.S. nearshore waters of Lake Huron.
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