Emerged Holocene South American Shorelines

A pelecypod from the Salina beds of northern Peru at elevation 4.5 m ( 15 ft) shows a date of about 3000 years B. P., while a gastropod from elevation 22.5 m (75 ft) was older than 30,000 years B. P. A pelecypod from the island of Tierrabomba, near Cartagena, Colombia, at elevation 2.7 m ( 9 ft) gave a date of about 2850 years, while a pelecypod from Comodoro Rividavia, Argentina, at elevation 9 m ( 30 ft) gave a date of 5350 years B. P.     

Market stress-associated changes in serum complement activity in feeder calves.

Classical hemolytic complement (C) of calves was analyzed during a protocol designed to imitate the usual market handling of feeder calves from the southeastern United States. Serum C concentrations of the calves (n = 100 x 4 years) were evaluated on their farm of origin, on arrival at an auction market, on arrival at a feedyard, and during their first 4 weeks in the feedyard. Complement concentrations (measured in CH50 units) were typically lowest at the farm of origin and highest when the calves entered the auction market 28 to 133 days later. Serum C concentrations decreased after the calves encountered the severe stresses of being in the auction market for 7 days, 24-hour truck transport (1,932 km) to the feedyard, and the first 7 days in the feedyard. The C concentrations recovered after 21 to 28 days in the feedyard. Steers had significantly (P less than or equal to 0.05) lower C concentrations than did heifers in 3 of 4 years at the farm of origin, and in 2 of 4 years at the auction market. Morbid calves had significantly (P less than or equal to 0.05) lower C values than did healthy calves on day 7 in the feedyard in 3 of 4 years. There were significant differences in C concentrations of calves from different farms of origin in each of the 4 years. There was no significant difference in C concentrations of calves that were vaccinated vs those not vaccinated with Pasteurella haemolytica.     

The effect of a 50% inspired mixture of nitrous oxide on arterial oxygen tension in spontaneously breathing horses anaesthetised with halothane

The effect of nitrous oxide (N₂O) on arterial partial pressure of oxygen (P_aO₂) was evaluated in 20 adult horses anaesthetised with halothane. A fresh gas flow rate of 20ml/kg/min, comprising a 1:1 N₂O/oxygen (O₂) mixture, was supplied via the rotameter flowmeters of an anaesthetic machine to a large animal breathing system. The horses breathed spontaneously from the circuit immediately after endotracheal intubation. Ten horses were subsequently positioned in lateral recumbency and ten in dorsal recumbency. A further twenty adult horses were anaesthetised with halothane and acted as controls; halothane in 20mls/kg/min of O₂ being supplied to the same breathing system. Fifty percent NO caused significant decreases in P_aO₂ for horses in lateral and dorsal recumbency. However when administered to horses in lateral recumbency it did not promote arterial hypoxaemia. There was a higher risk of intraopera- tive arterial hypoxaemia (P_aO₂ < 8.6kPa) associated with its use in spontaneously breathing horses in dorsal recumbency. Arterial hypoxaemia occurred in all horses during the first fifteen minutes of recovery but when N₂O was discontinued, halothane in oxygen supplied to the breathing circuit for five minutes at a flow rate of 20ml/kg/minute was sufficient to ensure that diffusion hypoxia did not occur. The magnitude of the hypoxaemia was not signficantly different between the groups. The time taken to adopt sternal recumbency was significantly shorter in the horses that had received N₂O.     

Amoxycillin in the control of furunculosis in Atlantic salmon parr.

The efficacy of amoxycillin in the control of laboratory induced Aeromonas salmonicida infection in Atlantic salmon parr was investigated. When given in the diet at a dose rate of 80 mg per kg bodyweight it was effective against both a moderate and severe challenge (with mortality rates in untreated groups of 75 per cent and 45 per cent). At 40 mg per kg it was effective against the moderate challenge only. The plasma levels in these regimens were 1.25 micrograms per ml and 0.3 to 0.6 micrograms per ml and the minimum inhibitory concentration of the challenge strain of A salmonicida was 0.6 micrograms per ml. The potential of the Charm radiobioassay system in detecting antibiotic residues in fish tissue was studied. The level of amoxycillin in muscle and bone from fish in mid-treatment at 80 mg per kg was 0.32 micrograms per ml. After a 12 day withdrawal period at 18 degrees C no residue was detected within the 0.005 micrograms per ml limit of this test.     

Acromegaly in 14 Cats

Acromegaly was diagnosed in 14 middle-aged to old cats of mixed breeding. Thirteen (93%) of the cats were male and one was female. The earliest clinical signs in the 14 cats included polyuria, polydipsia, polyphagia, all of which were associated with untreated diabetes mellitus. All developed severe insulin resistance within a few months; peak insulin dosages required to control severe hyperglycemia ranged from 20 to 130 U per day. Other clinical findings weeks to months after diagnosis included enlargement of one or more organs (e.g., liver, heart, kidneys, and tongue) (n = 14), cardiomyopathy (n = 13), increase in body size and weight gain (n = 8), nephropathy associated with azotemia and clinical signs of renal failure (n = 7), degenerative arthropathy (n = 6), and central nervous system signs (i.e., circling and seizures) caused by enlargement of the pituitary tumor (n = 2). The diagnosis of acromegaly was confirmed by demonstration of extremely high basal serum growth hormone concentrations (22 to 131 micrograms/l) in all cats. Computerized tomography disclosed a mass in the region of the pituitary gland and hypothalamus in five of the six cats in which it was performed. Two cats were treated by cobalt radiotherapy followed by administration of a somatostatin analogue (octreotide), whereas two cats were treated with octreotide alone. Treatment had little to no effect in decreasing serum GH concentrations in any of the cats. Eleven of the 14 cats were euthanized or died four to 42 months (median survival time, 20.5 months) after the onset of acromegaly because of renal failure (n = 2), congestive heart failure (n = 1), concomitant renal failure and congestive heart failure (n = 3), progressive neurologic signs (n = 2), persistent anorexia and lethargy of unknown cause (n = 1), the owner's unwillingness to treat the diabetes mellitus (n = 1), or unknown causes (n = 1). Results of necropsy examination in ten cats revealed a large pituitary acidophil adenoma (n = 10), marked left ventricular and septal hypertrophy (n = 7), dilated cardiomyopathy (n = 1), arthropathy affecting the shoulder, elbow, or stifle (n = 5), and glomerulopathy characterized by expansion of the mesangial matrix and variable periglomerular fibrosis (n = 10).     

The efficacy of triclabendazole and other anthelmintics against Fasciola hepatica in controlled studies in cattle

In eight controlled tests 274 cattle were used to assess the efficacies of triclabendazole, albendazole, clorsulon, nitroxynil, oxyclozanide and rafoxanide against Fasciola hepatica. Against one-, two- and four-week-old early immature fluke the mean efficacies of triclabendazole given orally at 12 mg/kg were 88.1, 95.3 and 90.7 per cent, respectively. Clorsulon, nitroxynil and rafoxanide administered at recommended dose rates showed negligible activity against these stages of the parasite. Against six- and eight-week-old infections the mean efficacies of triclabendazole at 12 mg/kg were 87.5 per cent and 95.7 per cent, respectively. Against F hepatica aged six weeks, albendazole and oxyclozanide showed no activity and clorsulon, nitroxynil and rafoxanide had only slight to moderate activity. The efficacies of triclabendazole, clorsulon, nitroxynil and rafoxanide against 10- or 12-week-old parasites were 100, 99.0, 99.1 and 90.1 per cent, respectively. Albendazole and oxyclozanide showed poor efficacy against 12-week-old infections.     

Pleistocene age determinations from california and Oregon

Mollusks have been collected from Pleistocene marine deposits at Tomales Bay, California, and Cape Blanco, Oregon. Dating by the carbon-14 and thorium-230-uranium-234 methods suggests that the shells are at least 33,000 years old. The more probable age of the Tomales Bay locality is >/= 50,000 years.     

Bovine spongiform encephalopathy: diagnostic significance of vacuolar changes in selected nuclei of the medulla oblongata

The adequacy of a histopathological diagnosis of bovine spongiform encephalopathy (BSE) based exclusively on observations of neuroparenchymal vacuolation in three specific neuroanatomic nuclei was tested by using a standard coronal section of medulla oblongata cut at the obex. The agreement between the observations and the definitive histopathological diagnosis was assessed in each of 684 bovine brains - 563 confirmed cases of BSE, 20 with changes which did not diagnose BSE conclusively and 101 in which the lesions of BSE were not detected. When the assessment was confined to the solitary tract nucleus and the spinal tract nucleus of the trigeminal nerve a positive result was obtained in 99.6 per cent of confirmed cases of BSE and only 1 per cent of brains in which lesions of BSE were not detected gave a false positive result. Thus an initial examination of the single section, together with an examination of representative areas of the rest of the brain when no unequivocal lesion was found, provided a satisfactory method for the routine diagnosis of BSE.