Lead, cadmium, and fluoride levels in market milk and infant formulas in Canada

Lead, cadmium, and fluoride were determined in 68 samples of market milk and about 115 infant formulas. Mean and median levels (ranges) in ng/g found for cow milk were as follows: lead, 1.12, 1.19 (0.01-2.48); cadmium, 0.10, 0.039 (0.005-0.74); and fluoride, 41, 40 (7-86). In canned, ready-to-use formulas, lead, cadmium, and fluoride levels averaged 37.3, 1.50, and 840 ng/g, respectively. In concentrated liquid formulas, the respective levels were 21, 3.54, and 600 ng/g. In powder formula concentrates, respective levels were 73.7, 6.78, and 1130 ng/g. On the basis of this study and literature data, lead levels in market milk exceeding 5 ng/g appeared to signify contamination of the milk either directly or via the cow. For formulas considered on an as-consumed basis, lead levels exceeding about 10-15 ng/g were attributed to contamination from either the can used to store the formula or the formula ingredients. Infant formulas in lead-free cans contained about 1.7 ng/g of lead on a ready-to-use basis. Milk-based formulas contained about 0.26 ng/g of cadmium on a ready-to-use basis. Soy-based or milk-free formulas contained about 8-15 times more cadmium than did milk-based formulas. Canadian and U.S. ready-to-use formulas contained 900 and 230 ng/g fluoride, respectively, and this difference was attributed to the level of fluoride in the processing water used by the manufacturers.     

No place to nest or bask: Effects of human disturbance on the nesting and basking habits of yellow-blotched map turtles (Graptemys flavimaculata)

Considerable recent attention has focused on how human disturbance alters the behaviour of imperiled taxa. Data on such impacts are common for waterfowl, marine mammals, and some large game animals. However, little is known about how human disturbances affect reptiles, perhaps because most reptiles are secretive and are not commonly seen by the public. We studied the impact of human disturbances on the nesting and basking behaviour of the yellow-blotched map turtle (Graptemys flavimaculata) on the Pascagoula River in southeastern Mississippi, USA. We found that both nesting and basking behaviour of map turtles were altered by human recreational activities. Turtles attempting to nest commonly abandoned their attempts upon the approach of a boat and, prior to nesting, numerous individuals waited several hours near the beach without emerging. Basking turtles frequently dove into the water upon the approach of a boat and some did not return to bask. Anglers in small boats that remained in the vicinity of basking sites caused the most disturbances, whereas personal water crafts (jet skis) caused fewer disturbances. Our data suggest that interruption of nesting activities may have an especially severe impact on the viability of this population through changes in numbers of clutches females are able to lay and altering the microhabitat females select for their nests.     

Pinch-induced behavioral inhibition ('clipnosis') in domestic cats

Research has documented immobilization of rodents, rabbits, guinea pigs and dogs by mechanical means, typically using neck clips or inversion ('animal hypnosis'). In contrast, only a few studies of mechanical immobilization of cats are available, although some success has been reported in the literature. Domestic cats may be effectively immobilized by clips placed along the animal's dorsum. We use the term 'pinch-induced behavioral inhibition' (PIBI) for this behavior because it describes both the method and the response, while avoiding the more anthropomorphic term 'hypnosis'. We investigated the effectiveness of PIBI and its neurological and habituation effects in healthy cats and cats with idiopathic cystitis (IC). Although not all cats were susceptible to PIBI and effectiveness varied among individuals, PIBI was useful for gentle restraint in most cats.     

Intracranial medulloblastoma as the cause of progressive ataxia in a 6-month-old draft horse cross gelding

We describe the unique clinical presentation of a central nervous system neoplasm in a 6-month-old draft horse cross gelding. Based on the neurologic examination at admission, neurolocalization was most consistent with a mildly asymmetric cervical, multifocal, or diffuse myelopathy. Mild vestibular involvement also was considered, but no cranial nerve deficits were observed. The gelding was negative for Sarcocystis neurona or Neospora hughesi based on paired serum and cerebrospinal fluid (CSF) samples analyzed, with no evidence of cervical compression based on contrast myelography. The horse was euthanized because of progression of clinical signs. At necropsy, a mass was identified associated with the cerebellum, and histopathology was consistent with medulloblastoma, which has not been reported previously in the horse.     

The Drought Calculator: Decision Support Tool for Predicting Forage Growth During Drought

The Drought Calculator (DC), a spreadsheet-based decision support tool, was developed to help ranchers and range managers predict reductions in forage production due to drought. Forage growth potential (FGP), the fraction of historical average production, is predicted as a weighted average of monthly precipitation from January through June. We calibrated and evaluated the DC tool in the Great Plains of the United States, using FGP and precipitation data from Colorado (CO), North Dakota (ND), and Wyoming (WY). In CO, FGP was most sensitive to precipitation in April and May, in ND to precipitation in April and June, and in WY to precipitation in April, May, and June. Weights in these months ranged from 0.16 to 0.52. Prediction was better for CO and WY than for ND. When January–June precipitation was used, the tool correctly predicted 83% of the years with FGP reduced by drought for CO, 82% for WY, and only 67% for ND. Positive values of the True Skill Statistic (0.53 for CO, 0.42 for WY, and 0.17 for ND) indicate that FGP was classified as above or below average better than random selection. Predicting FGP earlier than April in CO and WY will require accurate forecasts of April–June precipitation. Use of the DC is most limited by insufficient forage data to determine the site-specific relationships between FGP and monthly precipitation. Even so, the decision tool is useful for discriminating drought effects on FGP classification being above or below the long-term average, and it provides a quantitative prediction to producers for their destocking decisions in drought years.     

Intraruminal controlled release of cyromazine for the prevention of Lucilia cuprina myiasis in sheep

The efficacy of cyromazine, continuously released from intraruminal capsules at dose rates from 0.5 to 2 mg kg-1 d-1, was evaluated against implants of eggs and first instar larvae of Lucilia cuprina on Merino sheep. Estimates from the non-linear relationship between the success of implants and plasma concentrations showed that 95 per cent protection of sheep could be achieved at a mean release rate of 1.39 mg kg-1 d-1 cyromazine which gave rise to a mean plasma concentration of 0.26 mg litre-1. Present formulations allowed protection for about 90 days in a 40 kg sheep. The 'square wave' type of release profile provided negligible suboptimal dosing thus limiting the potential for selection of resistance. Systemic application of cyromazine provides control of covert and overt strike among sheep and could be used in ecologically based strategies for the control of L. cuprina populations.     

Uptake of the systemic fungicide triadimefon by clover and its effect on symbiotic nitrogen fixation

Clover is frequently grown in rotation with cereals in order to increase soil nitrogen. The systemic fungicide triadimefon, widely used against cereal pathogens, is readily taken up from soil by clover and degraded to a single major metabolite. Plant weight and symbiotic nitrogen fixation by Rhizobium trijolii are affected only by concentrations of triadimefon in soil that are much in excess of those likely to be encountered in practice. Triadimefon residues are thus unlikely to affect nitrogen fixation by clover under field conditions.     

BOVINE ENZOOTIC HAEMATURIA IN QUEENSLAND

Bovine enzootic haematuria was diagnosed in Queensland in coastal areas in association with bracken fern (Pteridium esculentum) on 3 properties or with mulga fern or rock fern (Cheilanthes sieberi) on 4 properties, and in inland areas in association with C. sieberi on 3 properties. In the absence of bracken fern, long-term ingestion of C. sieberi is suggested as a cause of bovine enzootic haematuria. Haemangiomas, haemangiosarcomas, transitional cell carcinomas, papillomas, fibromas and an adenoma were detected in the urinary bladders of 19 affected cattle and were accompanied by chronic cystitis.     

Long term consequences of low birthweight on postnatal growth, adiposity and brain weight at maturity in sheep

Low birth weight (LBW) as a result of restricted fetal growth increases the risk for later metabolic diseases and adiposity. However the relationship between LBW and postnatal growth and adult body composition has not been fully investigated. We have used sheep to determine the effects of LBW on postnatal growth and body composition at maturity. LBW was induced by twinning and placental embolization. At birth, LBW lambs were 38% lighter than controls (2.8 +/- 0.2 vs 4.4 +/- 0.3 kg, P<0.05), but had caught up in bodyweight by 8 weeks after birth. At approximately 2.3 years, bodyweights were not different between groups, but there were reductions in absolute (-8%) and relative (-17%) brain weights of LBW sheep (P<0.05) compared to controls. X-ray absorptiometry showed that the mature LBW sheep, compared to controls, had greater amounts of lean muscle (38.1 +/- 1.3 vs 35.3 +/- 0.5 kg, P<0.05) and tended to have more body fat (12.2 +/- 1.2 vs 9.6 +/- 0.9 kg; P=0.1); at autopsy abdominal fat mass was greater in LBW sheep (3.06 +/- 0.26 vs 2.20 +/- 0.25 kg, P<0.05). Plasma leptin concentrations were not different between groups. We conclude that, in sheep, LBW is associated with early postnatal catch-up in body weight, but body composition is permanently altered such that, relative to controls, adiposity is increased and brain weight is decreased.