Occurrence and pathology of intracutaneous cornifying epitheliomas in Mastomys natalensis, the multimammate mouse

Twelve mastomys (Mastomys natalensis) about two years old developed several raised, varying sized, multiple scurfy growths on most of the external parts of the body over a period of two months. No metastatic lesions were observed in the internal organs at necropsy. Histological examination of the cutaneous lesions revealed that the growths were comprised of intracutaneous cornifying epitheliomas.     

The microflora of the lower respiratory tract of the horse: an autopsy study

A series of 31 thoroughbreds and 18 non-thoroughbreds was examined post mortem to assess what bacteria might be present in the lower respiratory tract, and to assess their significance by correlating the bacteriological findings with histological changes in the lung. The distal trachea and seven representative lung sites were swabbed in each case. Sixty-six per cent of the sites were sterile with remaining sites producing scanty growths of mainly coagulase negative Staphylococcus spp., E. coli, Bacillus spp. and Pseudomonas spp. Anaerobes, mainly Clostridium perfringens, Bacteroides fragilis and Bacteroides oralis, were only recovered on enrichment media and were isolated more frequently from the right lung than the left. More bacterial species were isolated from thoroughbreds than non-thoroughbreds. Significant inflammation was absent in the majority of lungs examined and this correlated well with the large percentage of sterile sites and low number of potential pathogens. The results indicate that the lower respiratory tract of horses is normally sterile or may contain small numbers of bacteria of low pathogenicity. Chlamydia and respiratory viruses were not isolated from any horse.     

Cutaneous papillomas associated with a herpesvirus-like infection in a herd of captive African elephants

Proliferative cutaneous lesions developed in a herd of captive African elephants (33 from an animal importer in Texas [group 1], and 63 young elephants collected in Zimbabwe [group 2]). Group-1 elephants were purchased 8 months before the arrival of the group-2 elephants. On arrival, 7 group-1 elephants had raised nodular fibrous growths, located predominantly on their trunks. Lesions were not observed in the group-2 elephants until approximately 3 months after they were acquired. Lesions on group-2 elephants began as small focal proliferative growths that regressed or that progressed into large nodular fibrous growths that were similar in appearance to those seen in the group-1 elephants. Lesions at various stages of development were biopsied and examined. Histologically, early lesions were inverted papillomas, with hyperplastic and hypertrophic epithelial cells containing amphoteric intranuclear inclusions in the lesion center. Older, large, nodular fibrous growths were ulcerated and were composed predominantly of a thickened dermis containing fibroblasts, collagen, and a mixed inflammatory cell infiltrate; inclusions were not observed in adjacent epidermal cells. Using a peroxidase-antiperoxidase technique, we did not detect group-specific papillomavirus antigens. Southern blot hybridization analysis of DNA from lesion specimens did not indicate papillomavirus-specific genomes. Electron-microscopically, inclusions consisted of aggregates of virus particles. The particles had electron-dense and electron-lucent cores and were 95 to 103 nm in diameter. Virions developed envelopes from nuclear membranes. Mature particles were seen within the cytoplasm and filled the intercellular spaces. On the basis of size, location, conformation, and envelopment, the particles most closely resembled those of herpesviruses.     

Generalized nodular dermatofibrosis and renal cystadenocarcinomas in a German shepherd dog

Generalized, nodular dermatofibrosis with coexisting bilateral renal cystadenocarcinomas was diagnosed in a 6-year-old male German Shepherd Dog. Approximately 3 years earlier, the dog had been examined because of lameness attributable to 2 nodular growths between the third and fourth digits of the right front limb. Biopsy revealed dense collagenous dermal fibrosis, often in a nodular arrangement. As the disease progressed, attempts to alleviate the discomfort and lameness caused by the nodular growths were performed by surgical excision. During this period, other nodular growths that developed apparently did not bother the dog. Because of the long and protracted clinical progression of the disease and poor prognosis for successful treatment, the dog was euthanatized. At necropsy, multiple multicentric nodules were found in the skin and subcutis, with most located on the limbs. The nodules were well-circumscribed and hard. Epithelial ulceration and inflammation were confined to nodules on the feet. Small foci of collagenous proliferation were found along fascial planes. In addition, cystic neoplasms were in both kidneys. The microscopic diagnosis was generalized nodular dermatofibrosis, with bilateral renal cystadenocarcinomas.     

白沙蒿杀虫活性初探

白沙蒿(Artemisia sphaerocephala)是典型的流动沙丘植物,非常适应干旱荒漠地区的极端气候,是沙漠荒漠化治理和恢复中优良的固沙植物之一。植物中的次生代谢物是其适应不利环境因素的重要策略之一。本研究首次开展了白沙蒿提取物对朱砂叶螨(Tetranychus cinnabarinus)和斜纹夜蛾(Spodoptera litura)幼虫的活性测试,并对受体植物油菜(Brassica campestris)、紫花苜蓿(Medicago sativa)、红三叶(Trifolium pratense)和早熟禾(Poa annua)的植物毒活性也进行了检测。结果表明,白沙蒿提取物对两种害虫均表现出具有较强的杀螨活性,但对农作物油菜和牧草红三叶、紫花苜蓿和早熟禾的生长没有明显影响。在低浓度时,还对紫花苜蓿和早熟禾的生长有一定的促进作用。浓度为333μg·m L-1时,对朱砂叶螨的触杀活性大于60%,在20μg·m L-1的浓度下对斜纹夜蛾幼虫的触杀活性大于50%,而在50和25μg·m L-1浓度下对苜蓿和早熟禾有促进作用,对油菜和红三叶的抑制率小于20%。     

Grey horse melanotic condition: A pigmentary disorder

We have worked with a total of 58 grey coated horses affected with generalized progressive leukotrichia, mainly (95%) Spanish Pure Breed (SPB) or crossbreed with a high percentage of this breed, the ages ranging between 6 months and 23 years old and mainly males. Clinical studies, biopsies, necropsies, optic microscopy, and immunohistochemistry techniques were performed. In 52 (89%) of the 58 horses studied, dark melanotic (MN) was observed in diferent anatomic structures. The relationship between the progression of leukotrichia and the appearance of melanopathy, as well as the location, number, shape, size, and color of the growths were determined by clinical study. The structures and cellular types involved, as well as the pathogenic pattern, were determined through histologic and immunohistochemical studies. As a final conclusion, clinical, histological and immunohistochemical findings are suggestive of a non-neoplastic pigmentary disorder, maybe due to a failure in melanine degradation as the animal hair becomes progressively less pigmented as it ages.     

Intracutaneous cornifying epithelioma (keratoacanthoma) in the dog: a retrospective study of 25 cases.

The clinical, histopathologic, and behavioral features of 25 cases of intracutaneous cornifying epithelioma (ICE) in the dog were reviewed. A typical ICE consisted of a keratin-filled crypt in the dermis and subcutis that opened to the skin surface. Most of these tumors occurred on the back, neck, sides of the thorax, and the shoulders. Two distinct patterns existed-a solitary form (single growth) and a generalized form (up to 40 growths). The Norwegian Elkhound appeared to be a breed predisposed to the development of the generalized type. Breed predilection for the solitary form was not observed. The ICE was a benign neoplasm, and simple surgical excision was curative except in the generalized cases in which additional growths developed. Keratoacanthoma of man and ICE of the dog were compared, and it was concluded that although they are similar in many respects they are not identical entities.     

华北农牧交错带人工草地放牧系统植物补偿性生长研究

研究华北农牧交错带不同人工草地在不同放牧强度下的总净生长量及净生长量的变化.结果表明,无芒雀麦-杂花苜蓿草地在任何放牧强度下均表现为超补偿性生长,即净生长量增加;新麦草-杂花苜蓿和杂花苜蓿-新麦草-扁穗冰草草地在轻度放牧下,总净生长量增加,在中度和重度放牧条件下分别表现为等补偿性生长和欠补偿性生长;新麦草草地在轻牧下呈超补偿性生长,在中牧下为等补偿性生长,重牧时表现欠补偿性生长;杂花苜蓿净初级生产力变化同新麦草草地一致;无芒雀麦在所设放牧强度下均表现为超补偿性生长,表明其耐牧性极强.因此,草地放牧强度应根据其组成种群来确定,以保证可持续利用.     

海南热带海洋性气候对东北环颈雉生殖能力影响的研究初报

本文通过对由吉林引入海南省通什地区驯养的东北环颈雉生长发育情况的观察分析，首次证明：热带海洋性气候具有促进东北环颈雉产蛋量的显著提高和产蛋期极显著地延长的作用。为在海南扩大东北环颈雉的养殖，提供了理论依据。     

Peripheral giant cell granuloma in a cat

A gingival mass excised from a cat was determined to be a peripheral giant cell granuloma. Characteristic histologic features were large numbers of multinucleated giant cells intermixed with mononuclear mesenchymal cells in a loose fibrovascular stroma. The lesion recurred twice, indicating that these non-neoplastic growths may be locally invasive.     

冷胁迫对2种垂穗披碱草生长和生理特性的影响

低温是影响植物生长的外界限制因子之一。采用沙培法研究了冷胁迫对2种垂穗披碱草（Elymus nutans）（当雄垂穗披碱草（西藏野生）和甘南垂穗披碱草）生长与生理特性的影响。结果表明：冷胁迫处理5d显著抑制2种垂穗披碱草的生长和叶绿素的合成,特别是甘南垂穗披碱草发生严重氧化损伤,电解质渗透率和丙二醛（MDA）含量分别比对照增加114.7%和124.6%,而当雄垂穗披碱草受伤害较轻,分别比对照增加18.2%和10.8%。冷胁迫也显著增加了甘南垂穗披碱草中H₂O₂和自由基的积累,而当雄垂穗披碱草与对照相比差异不显著。冷胁迫处理5d后,当雄垂穗披碱草的类胡萝卜素含量较甘南增加72.3%,超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和过氧化物酶（POD）的活性分别较对照增加80.3%,27.3%和65.9%;甘南垂穗披碱草的SOD和POD活性分别较对照增加11.4%和28.9%,而其CAT活性下降25.5%。相关分析表明,垂穗披碱草在冷胁迫下细胞膜受损伤程度与抗氧化酶活性负相关。当雄垂穗披碱草通过提高抗氧化酶活性,可有效清除体内积累的活性氧,减轻细胞膜系统受损伤的程度从而提高其抗寒性。     

Mammary tumors in a colony of beagle dogs

In a lifetime study, female beagle dogs in a closed colony were administered 226radium and 90strontium. An unirradiated control group was included in the study. A total of 223 of 356 dogs at risk developed 1,112 mammary proliferative growths (hyperplastic nodules and neoplasms). There was no correlation between occurrence and types of lesions in radiation and control groups. The age range for first occurrence of lesions was 10.4 to 13.9 years; hyperplastic nodule and benign mixed tumor occurred 1 to 2 years earlier than other lesions. A multiplicity of growths of similar or different morphological type were common throughout the lifetime of the dog. The female beagles, collectively, developed 244 hyperplastic nodules, 78 adenomas, 694 benign mixed tumors, 78 carcinomas, 14 malignant mixed tumors, and four myoepitheliomas. Proliferations occurred with increasing frequency from the cranial to caudal mammary glands. Metastasis was found in 77% of the dogs with carcinoma. The median time from diagnosis to metastasis was 10 months, but was shorter in dogs with infiltrative carcinoma.     

A malignant neoplasm resembling a circumanal gland adenocarcinoma in a dog.

In the neoplasm of this report a final diagnosis of a circumanal gland adenocarcinoma invading the vertebral column and canal was made based on the histologic appearance. No growths were noted in the circumanal gland region and the location of the primary neoplasm is open to debate.     

Intestinal polyps in a lamb

Eight pedunculated jejunal polyps 4–13mm in diameter were found in a 3 to 5-month-old lamb during routine meat inspection at an export slaughterhouse in Canterbury. Histological examination revealed papilliform growths consisting of hyperplastic villi with numerous developmental stages of coccidia-like organisms in the epithelial cells of the polyps' mucosa. It is suggested that this specimen represents an uncommon manifestation of chronic ovine coccidiosis.     

人工草地群落组成与土壤中速效氮磷的关系

通过对白三叶和多年生黑麦草生物量在上壤速效磷氛比例梯度上变化模式的分析，验证了Tilman的群落组成变化的矿质营养比例学说。“以两种牧草生物量分别对土壤速效磷和速效氮二元线性回归的结果表明：磷和氮分别是白三叶和多年生黑麦草生长的限制因子。由此，二者可实现在土壤营养元素上的生态位分化而得以在人工草地群落中共存。     

Nature and cause of bilateral ocular dermoids in Hereford cattle

Nature and cause of bilateral ocular dermoids were investigated by field studies, pedigree analysis, clinical examination, light microscopy, scanning electron microscopy, and transmission electron microscopy. It was determined that ocular dermoids in Hereford cattle are a genetically transmitted defect; characteristics of autosomal recessive and polygenic inheritance were observed. Calves typically were affected bilaterally with multiple, connected ocular growths that clinically, histologically, and ultrastructurally mimicked normal haired skin. Sites most commonly involved included ventro-lateral limbus, third eyelid, medial canthus, eyelid and conjunctiva. Centro-corneal and anterior segmental dermoids also were observed.     

Hepatocellular adenocarcinoma in a white-tailed deer (Odocoileus virginianus).

A white-tailed deer (Odocoileus virginianus), shot during the 1978-79 New Jersey hunting season, was presented with an enlarged, multinodular liver and numerous skin growths. The skin lesions were found to be fibromas and the liver tumor was identified as a hepatocellular adenocarcinoma, a rare neoplasm, not only in deer but all wild animals.     

Atypical contagious ecthyma in a sheep after extensive cutaneous thermal injury

An atypical case of contagious ecthyma in a wether, following severe thermal injury to the skin, is reported. Histologically, extensive verrucous growths at the edges of the burned skin were areas of severe epidermal hyperplasia and hyperkeratosis. Intracellular viral particles were present, and sections of skin were positive for ovine contagious ecthyma virus by a fluorescent antibody test.