Lead poisoning in cattle and its implications for food safety

The lead poisoning incidents in cattle investigated by the Veterinary Laboratories Agency between 1990 and 2003 are reviewed. Lead poisoning was most commonly encountered in young calves, but cattle of all ages were affected. The lead was derived mainly from lead paint, lead accumulator batteries and lead in soil from old mine workings. Paint was responsible for the majority of cases of poisoning in young calves; yearling animals were most at risk from discarded batteries, and adult cows were most commonly poisoned by geochemical sources of lead. There was a marked seasonal incidence, with most cases occurring after turnout in the spring and early summer.     

Treatment of cervical vertebral instability in the dog.

In a retrospective study, common neurologic signs and results of treatment of cervical vertebral instabilities were reviewed. In 16 large dogs, vertebrae C5 and C6 were most frequently malformed and unstable. Treatment was conservative in 3 dogs, 1 dog was not treated, and 12 dogs were treated surgically (dorsal decompressive laminectomy and wire stabilization of the articular facets in most cases). The 3 conservative treatments and 8 of the 12 surgical treatments were considered beneficial.     

Clinical and laboratory findings in small companion animals with lead poisoning: 347 cases (1977-1986)

Three hundred forty-seven cases of lead poisoning in small companion animals were reviewed. The yearly prevalence and overall incidence rates were examined for the 10 years before and after enactment of strict federal regulations pertaining to lead content in paint products. Biographical data, clinical signs, and laboratory results were analyzed for the 6 types of affected animals (ie, dogs, cats, birds, rabbits, a chinchilla, and a raccoon). Clinical and laboratory findings of these animals were then compared with findings of other studies of lead intoxication.     

Vaginal hyperplasia in the bitch: Literature review and commentary

We reviewed the incidence, etiology, clinical presentations, diagnosis, treatments and prevention of canine vaginal hyperplasia, and describe a simple surgical technique for its correction as practiced at the Small Animal Clinic, State University of Utrecht, The Netherlands. Many different treatments have been used, and some are novel approaches. In many cases, prevention is accomplished if the bitch is ovariectomized; there is a high incidence of recurrence with medical treatment.     

Lead toxicosis in cats-a review

Although the incidence of lead toxicosis in small animals continues to decrease, it remains a significant malady. We have reviewed the literature of the past 45 years, which revealed 70 cases involving cats. Sources, signs, diagnosis, pathology and treatment of feline lead toxicosis are reviewed. In 84% of these cases the source of lead was old paint usually from home renovation. The most common signs in cats are anorexia, vomiting, and seizures. The younger individuals seem more likely to show CNS signs. Since signs are often vague, lead toxicosis may be significantly under diagnosed in cats. The gold standard of diagnostic tests is blood lead concentration, although it does not necessarily correlate with total body burden of lead or with metabolic effects including clinical signs. Diagnostic tests including erythropoietic protoporphyrin (EPP), urine aminolevulinic acid, and others are discussed. Gross findings on necropsy are few and include a yellow-brown discoloration of the liver often with a nutmeg-like appearance. Histological examination may reveal pathognomonic inclusion bodies in liver and renal tissues. Characteristic histological changes in the CNS include neuronal necrosis and demyelination. Treatment of lead toxicosis in cats, as in any species, involves removing the exposure, decontaminating the individual and the environment, supportive care and chelation therapy. The most recently available chelator is succimer (meso 2,3-dimercaptosuccinic acid). Succimer given orally is well tolerated and has a wide margin of safety. A high index of suspicion of lead toxicosis is warranted in cats since they often present with vague and non-specific signs. With any consistent history owners need to be asked about home renovation. Early diagnosis and treatment affords a good prognosis.     

Management of equine sarcoids: 1975–93

Treatment options for equine sarcoids are briefly reviewed and the results of a retrospective study of 63 cases of equine sarcoid (66 lesions) treated by clinicians from the Rural Veterinary Centre, Camden, Australia from 1975 to 1993 presented. Five different treatments were employed in the management of these 66 lesions, including surgical excision alone or in combination with cryotherapy, radiotherapy, immunotherapy and tumour transfer to a subcutaneous site on the neck. The majority of cases were treated with surgical excision alone (18/66), excision followed by cryotherapy (31/66) and immunotherapy (16/66), with success rates of 28%, 42% and 81% respectively. Success was defined as no sign of recurrence of the lesion at the time of follow-up, at least 6 months later.     

Management of equine sarcoids: 1975-93

Treatment options for equine sarcoids are briefly reviewed and the results of a retrospective study of 63 cases of equine sarcoid (66 lesions) treated by clinicians from the Rural Veterinary Centre, Camden, Australia from 1975 to 1993 presented. Five different treatments were employed in the management of these 66 lesions, including surgical excision alone or in combination with cryotherapy, radiotherapy, immunotherapy and tumour transfer to a subcutaneous site on the neck. The majority of cases were treated with surgical excision alone (18/66), excision followed by cryotherapy (31/66) and immunotherapy (16/66), with success rates of 28%, 42% and 81% respectively. Success was defined as no sign of recurrence of the lesion at the time of follow-up, at least 6 months later.     

Equine paranasal sinus disease: a long-term study of 200 cases (1997-2009): treatments and long-term results of treatments

Reasons for performing study: There is limited objective information available on the treatment and the long‐term response to treatment of the different types of equine sinus disease. Objectives: To document the treatments and long‐term response to these treatments in 200 cases of equine sinus disease (1997–2009). Methods: The treatments of horses affected with subacute primary sinusitis (n = 52); chronic primary sinusitis (n = 37); dental sinusitis (n = 40); sinus cyst (n = 26); traumatic (n = 13); dental‐related oromaxillary fistula (n = 8); sinus neoplasia (n = 10); mycotic sinus disease (n = 7); and intrasinus progressive ethmoid haematoma (n = 7) and the long‐term response to these treatments were retrospectively reviewed. Results: Treatments evolved throughout the study and latterly were as conservative as possible, including sinoscopic lavage and standing sinusotomy, with a maxillary sinusotomy approach preferred for the mainly mature horses treated in this study. Removal of intrasinus inspissated pus, including transendoscopically (by sinusotomy and via existing sinonasal fistulae), was the main treatment for chronic primary sinusitis and sinonasal fistulation was seldom performed latterly. Attempted oral extraction of infected cheek teeth, even if unsuccessful, facilitated subsequent dental repulsion, resulting in few post operative problems. Sinus cyst removal carried an excellent prognosis. Except for cases of sinus neoplasia (only 22% cured), an excellent long‐term response to treatment (91% fully cured, 7% partially cured) was obtained for all other types of sinus disease following a median of one treatment. Conclusions: More conservative treatments, including removal of intrasinus inspissated pus by sinoscopy, pre‐existing sinonasal fistula or sinusotomy, are effective for chronic primary sinus disease. Standing sinusotomy, mainly using a small maxillary site, was suitable for most cases of sinus disease in mature horses.     

Clinicopathological features of lymphosarcoma involving the thoracic cavity in the horse

The clinical and post mortem features of 11 cases of lymphosarcoma involving the thoracic cavity are reviewed. The clinical findings included inappetence, weight loss, pectoral oedema, dyspnoea, pleural effusion and distension of the jugular veins. Dysphagia was present in three cases. At post mortem examination lesions were found in the abdomen as well as the chest in eight cases; clinical signs of abdominal disease were present in two cases. The features of nine other similar cases recorded in the literature are reviewed.     

Surgical management of urinary incontinence.

Urethral sphincter mechanism incompetence and ureteral ectopia are the two most common causes of urinary incontinence in dogs and cats. Surgical treatments for both disorders have been described.Once a diagnosis is made, surgical intervention may lead to improved outcomes with resolution of incontinence in many patients. Proper case selection and surgical technique are critical in achieving clinical success when managing these difficult cases.     

Strategies for reduced antibiotic usage in dairy cattle farms

The need for antibiotic treatments in dairy cattle farms can be reduced by a combined intervention scheme based on: (1) timely clinical inspections, (2) the assessment of animal-based welfare parameters, and (3) the use of predictive laboratory tests. These can provide greater insight into environmental adaptation of dairy cows and define animals at risk of contracting disease. In the long-term, an improved disease control justifies the adoption of such a combined strategy. Many antibiotic treatments for chronic disease cases are often not justified with a cost/benefit analysis, because the repeated drug administration does not give rise to the expected outcome in terms of animal health. In particular, compared with untreated cases, antibiotics may not lead to greater cure rates for some forms of mastitis. Lastly, a substantial reduction of antibiotic usage in dairy farms can be achieved through the proper use of immunomodulators, aimed at increasing immunocompetence and disease resistance of cows.     

Lymphangiosarcoma of dogs: a review

Lymphangiosarcoma in dogs, an extremely rare tumour with only 16 cases reported in the literature, is reviewed. Lymphangiosarcoma in humans, also very rare, and known in post-mastectomy, chronically-lymphoedematous patients as 'Stewart-Treves' syndrome, is briefly outlined, as well as the various other causes of lymphoedema, both primary and secondary, which usually precede malignancy. Comparisons between human and canine lymphoedema are made when such references were found. The genetic links to primary lymphoedema and the manifestation thereof in humans are mentioned. Lymphangiosarcoma in the majority of human and canine patients is an aggressively malignant tumour with few patients surviving despite various attempted treatments. The tumour most commonly arises in the subcutaneous tissues and rapidly invades underlying tissues and may spread widely internally via haematogenous and lymphatic routes, with frequent pleural and chest involvement. The tumour has been reported mostly in medium- to large-breed dogs, in slightly more males than females, and in an age-range of 8 weeks to 13 years, with more cases aged 5 years and older. Methods of diagnosis, with the variations encountered, including routine histopathology, immunohistochemistry, electron microscopy, tissue culture characteristics and endothelial expression of glycocongugates, are discussed.     

牛卵母细胞胞浆内单精子注射的研究进展

本文叙述了牛卵胞浆内单精子注射(intracytoplasmic sperm injection ICSI)的研究进展。主要分析了前期处理精子对ICSI的影响,比较了各种激活处理对ICSI的提高效果,展望了ICSI的应用前景。     

Experimental control of the process of lead absorption and deposition in domestic ducks

A trial was conducted with 40 domestic ducks of the White Pekin breed at the age of 40 days: thirty pieces of lead shot were introduced as a single dose in the gizzard. The process of lead resorption and deposition was found not to be significantly influenced by the therapeutic treatments nor changes in the composition of feed. A week after the administration of shot a significant increase was recorded in the content of lead to 4.32 mg in liver, to 11.36 mg in kidney and to 1.15 mg in muscle (the respective values for the control animals were 0.07, 0.11 and 0.06 mg per kg). At the end of the trial after three weeks of treatment and administration of experimental diets, no significant differences were recorded in lead content in liver, kidney and muscle between the untreated and treated ducks nor ducks fed experimental diets.     

Influence of Montmorillonite Nanocomposite on Tissue Levels of Lead and Blood Biochemical Parameters in Pigs Exposed to Lead

Eighteen (Duroc × Landrace × Yorkshire) castrated boars,55 days of age and weighing approximately 19 kg,were used to investigate the effects of montmorillonite nanocomposite on tissue levels of lead as well as changes in blood biochemical parameters in pigs fed lead contaminated diets.The barrows were randomly assigned to one of three treatments (n=6) including a control which were fed a basal diet based on corn and soybean meal.The remaining two groups were fed the basal diet supplemented with 10 mg/kg lead either with or without 0.5% montmorillonite nanocomposite for 50 days.Pigs treated with lead had significantly increased levels of lead in their tissues.Lead accumulated in all tissues of the body with the highest accumulation found in the hair.When montmorillonite nanocomposite was given along with lead,tissue concentrations of lead did not differ from the control.Fecal excretion of lead increased significantly in lead-exposed pigs treated with montmorillonite nanocomposite.A progressive and appreciable accumulation of lead was seen in blood with a concomitant increase in zinc protoporphyrin levels during the course of treatment.However,zinc protoporphyrin levels did not differ from the control when montmorillonite nanocomposite was administered along with lead.The activity of δ-amino levulinic acid dehydratase in blood was significantly increased in lead treated pigs compared with the control.However,in pigs treated with lead and montmorillonite nanocomposite in combination,the activity of δ-amino levulinic acid dehydratase was similar to control pigs.Our results indicate that montmorillonite nanocomposite treatment of pigs exposed to lead resulted in reduced lead concentrations in body tissues.It appears that montmorillonite nanocomposite functions by increasing fecal excretion of lead.     

Retrospective analysis of nonradiation complications in dogs undergoing radiation therapy

Dogs receiving radiation can develop complications unrelated to the radiation treatment. No study to date has described these complications in clinical patients undergoing multiple radiation therapy treatments. The purpose of this retrospective case‐control study was to characterize the incidence and type of complications that occur in these dogs. A secondary goal was to evaluate whether patient and treatment characteristics could be identified to predict the risk of these complications. Medical records of 268 dogs receiving at least one radiation treatment at a single institution, between September, 2004 and June, 2007 were reviewed. Age, breed, gender, body weight, tumor type, tumor location, number of treatments, pre‐treatment blood work abnormalities, and whether chemotherapy, glucocorticoids, or nonsteroidal anti‐inflammatory drugs were given were collected. Number, type, and severity of nonradiation complications were recorded. Complications attributed to the tumor or to the radiation were excluded. Statistical analyses were performed to determine whether demographic and clinical characteristics were associated with development of a complication. General anesthesia was used for all treatments. Complications occurred in 101 (37%) cases including diarrhea, vomiting, cough, and loss of appetite, which were typically mild. Seventeen dogs (6%) developed severe complications. Eight dogs (3%) died from their complication. Dogs that developed complications were younger, received more treatments, had leukocytosis, received glucocorticoids, and were less likely to have thrombocytopenia. On multivariate analysis, number of treatments and leukocytosis were significantly associated with complications. Findings indicate that nonradiation complications are common in dogs receiving radiotherapy under general anesthesia. In this population, complications were usually mild or self‐limiting.     

Development of equine post anaesthetic myelopathy: Thirty cases (1979–2010)

Post anaesthetic myelopathy is a rare but devastating complication of equine anaesthesia and there is a need for better understanding of the condition and to raise veterinary awareness. The aim of this study was to collect data on unreported cases and combine those with reported cases to better identify possible risk factors and early clinical signs and outcomes of horses developing post anaesthetic myelopathy (PAM). A survey was conducted to identify cases of equine PAM. Records were also requested via the American College of Veterinary Anaesthesiologists listserve. Additional cases of PAM were located through review of the literature. Eighteen new cases and 12 published cases were identified. Large‐framed breeds between 6–24 months of age were more commonly affected (23/30). The majority of horses were positioned in dorsal recumbency during anaesthesia. Lack of movement and deep pain of the rear limbs, loss of anal tone and lack of panniculus response from the mid to caudal thorax distally were the most common clinical findings. Reported treatments resulted in no improvement of clinical signs and all horses died or were subjected to euthanasia from a few hours to 8 days post operatively. Poliomyelomalacia of the caudal spinal cord is the most common histopathological finding. Although a rare complication it is a catastrophic risk that can be eliminated by performing a standing operation. Hopefully in the future better understanding of this condition will lead to prevention and treatment strategies.     

Solid intraocular xanthogranuloma in three Miniature Schnauzer dogs

OBJECTIVE: Macrophages that contain abundant intracytoplasmic lipid are called 'foam cells'. In four canine globes submitted to the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW), foam cells formed a solid intraocular mass. The purpose of this study was to describe the histopathologic findings in these cases. PROCEDURE: The electronic COPLOW database (1993-2006) was searched for the diagnosis of 'foam cell tumor'. Clinical history, gross pathology and histopathology (5-micron sections, hematoxylin and eosin and Alcian blue periodic acid Schiff) were reviewed in all cases. Cases were included if the globe was grossly filled by a solid mass and if all intraocular structures were effaced by lipid-laden foam cell macrophages admixed with birefringent, Alcian blue-positive crystals oriented in stellate patterns. RESULTS: All three patients (four globes) satisfying the selection criteria were Miniature Schnauzers. In all cases the clinical history included diabetes mellitus, hyperlipidemia and chronic bilateral uveitis that was interpreted to be lens-induced. All globes were enucleated because of glaucoma. CONCLUSIONS: The term solid intraocular xanthogranuloma was used to describe these cases because the intraocular contents were effaced by a solid mass of foam cells and birefringent crystals. The cases in this report suggest that diabetic Miniature Schnauzers with hyperlipidemia are at risk for lipid and macrophage-rich uveitis, which may in some cases form a solid inflammatory intraocular mass, precipitate glaucoma, and lead to enucleation.     

Filaroides osleri (Oslerus osleri): two case reports and a review of canid infections in North America

Infections of domesticated dogs by a worldwide parasitic nematode Filaroides osleri (Oslerus osleri) lead to verminous tracheobronchitis that are often misdiagnosed clinically as kennel cough, due to infection with the bacterium Bordetella bronchiseptica. Diagnosis of two canine cases in Wyoming, USA prompted a search of the literature of canid infections in North America. Infections of domestic dogs are reported in nine US states and four Canadian provinces. Dogs of multiple breeds and both sexes were infected. Most were two years old or younger at diagnosis. Anthelmintic treatments were effective in relieving clinical symptoms, as well as causing resolution of tracheobronchial nodules. Other canid species, including coyotes (Canis latrans) and wolves (Canis lupus), have been infected across North America with a prevalence of 23% and 4%, respectively. Infection with F. osleri should be included in the differential diagnosis of infectious tracheobronchitis of dogs. It can be confirmed most readily by endoscopic detection of distinctive submucosal parasite-filled nodules, combined with histological examination of endoscopic biopsies.     

沸石净化养殖水体的研究进展

沸石由于比表面积大、吸附性能高、离子交换性良好，还可做为理想的生物载体，已在环保和饲料工业领域中得到了广泛的应用。本文从沸石的结构和功能展开，综述了其在养殖水体净化中去氨增氧、减少赤潮发生、治理富营养化水体以及培养生物沸石处理养殖废水等的应用。并进一步展望了沸石分子筛吸附微生物组合来改善养殖水体底泥的可能性，沸石的活化、改性和复合工艺更将拓展沸石净化养殖水体能力。