Avocado (Persea americana) intoxication in caged birds

Avocados of 2 varieties were mashed and administered via feeding cannula to 8 canaries and 8 budgerigars. Two control budgerigars were given water via feeding cannula. Six budgerigars and 1 canary died within 24 to 47 hours after the first administration of avocado. Deaths were associated with administration of both varieties of avocado. Higher dose was associated with greater mortality. The 2 budgerigars given water were normal throughout the observation period. Results indicated that avocados are highly toxic to budgerigars and less toxic to canaries. Postmortem findings observed in some birds included subcutaneous edema in the pectoral area and hydropericardium.     

油梨突脐蠕孢叶斑病病原菌鉴定及室内防治药剂筛选

【目的】为明确在广西崇左市油梨种植基地发现的一种叶斑病的病原菌及其生物学特性,以及该病害的防治药剂。【方法】通过形态学鉴定及分子生物学方法,对该病原菌进行鉴定,并对该病原菌进行了生物学特性测定及防治杀菌剂的室内筛选。【结果】该叶斑病的病原菌为嘴突脐蠕孢（Exserohilum rostratum）,该病原菌的最适生长温度为28℃,最适培养基为PDA培养基,最适pH为7,黑暗条件有利于该菌的生长。参试的250g/L吡唑醚菌酯乳油、10%苯醚甲环唑水分散粒剂、40%百菌清悬浮剂、430g/L戊唑醇悬浮剂和40%腈菌唑可湿性粉剂对嘴突脐蠕孢均有抑制效果,其中10%苯醚甲环唑水分散粒剂、430g/L戊唑醇悬浮剂和40%腈菌唑可湿性粉剂对该菌生长的抑制效果较好,其EC50分别为0.0163mg/L、0.0420mg/L、0.1109mg/L。     

种子纵剖对油梨发芽的影响

对油梨种子进行全核（对照）及三种不同纵剖方法处理（剖成1/2、1/4和1/6剖片）,并对发芽率、成苗数、发芽时间及幼苗长势等性状比较分析。结果表明,油梨种子的发芽率、发芽时间、幼苗长势基本与种子剖片数呈负相关,但剖片后,一枚种子的成苗数比全核（对照）多。综上所述,1/2纵剖处理后种子的发芽率、成苗数、发芽时间及幼苗长势等指标较为理想。     

Thermal changes in cow's mammary gland after experimentally invoked inflammation (mastitis)

The purpose of the study was the evaluation of the thermal changes within mammary gland in cows, after experimentally invoked inflammation, developed as a result of 60 ml of 20% NaCl solution given directly into the udder (A and D quarters). Three hours after injection, the increased' temperature of teats and their bases by 2.26 degrees C and 0.58 degree C, respectively, was stated. The temperature was still increased after 6 hours from NaCl solution injection. It was accompanied by increase of heat flux from the skin surface by 50.17 mW/cm2 taken from the teat surface, and by increased values of Burton Index--the tissue blood supply index.     

甜菜碱对山羊产奶量和血液生化指标的影响

当前甜菜碱作为一种添加剂广泛应用于动物饲料中。甜菜碱是胆碱的氧化产物,在很多重要的生理代谢过程中具有代替蛋氨酸的作用。本试验通过在Mur-ciano-Granadina奶山羊的饲料中添加甜菜碱来研究对其产奶量和血液生化指标的影响。从拥有250只Murciano-Granadina奶山羊的饲养场选择60只泌乳期山羊,尽量保持年龄和胎次(2.5胎)的一致性。将山羊分为2个处理,每个处理30只羊,处理1饲喂基础饲料,处理2在基础饲料中添加4g/kg甜菜碱(此处所用甜菜碱为无水甜菜碱)。结果显示,饲喂添加甜菜碱饲粮的山羊与对照组相比具有较高的乳脂含量(分别为5.2%、4.8%,P0.05),在产奶量上添加甜菜碱组与对照组之间显著差异不显著(平均为1.8kg/d)。血液甘油三酯含量不同组别存在显著差异,对照组甘油三酯含量为0.76mmol/L,添加甜菜碱组甘油三酯含量为0.48mmol/L(P0.05)。甜菜碱对山羊乳汁成分影响的作用机理需要进一步研究。     

Characterisation of adiponectin and its receptors in the bovine mammary gland and in milk

Adiponectin is an adipocyte-derived hormone, which circulates in the form of homo-multimers. The individual oligomers have a distinct profile of activity, playing crucial roles in several biological processes, including metabolism and inflammation. Adiponectin exerts many of its effects by interacting with the receptors, AdipoR1 and AdipoR2. In the present study, mRNA expression of adiponectin, AdipoR1 and AdipoR2 was evaluated by quantitative PCR in different areas of the mammary gland in healthy lactating cows. The adiponectin isoforms in milk and blood were investigated by Western blotting and 2D-electrophoresis, and the presence of adiponectin protein was determined by immunohistochemistry.Low level expression of adiponectin mRNA was found in all areas of bovine mammary gland tissues examined. AdipoR1 and AdipoR2 mRNAs were also detected in mammary tissues and their expression was particularly prominent in the parenchyma and cistern. Western blotting revealed a heterogeneous electrophoretic pattern, indicating that different adiponectin isoforms exist in milk, compared with blood. In particular, milk shows a low molecular weight isoform of adiponectin, corresponding to the globular domain. Adiponectin in milk is characterised by a more complex 2D electrophoretic pattern, compared with blood, as illustrated by the presence of proteins of different molecular weights and isoelectric points. Adiponectin protein was detected by immunohistochemistry in epithelial cells lining the secretory alveoli, in secretum within the alveolar lumen and in small peripheral nerves. The study findings support a role for adiponectin in regulating metabolism and immunity of the bovine mammary gland and potentially the calf intestine, following ingestion of milk.     

The complement in milk and defense of the bovine mammary gland against infections

The mammary gland of dairy cows, which is prone to infection by various bacteria, mobilizes local and systemic immune defenses to cope with pathogens. The complement system plays an important part in the innate immunity against microorganisms through its bactericidal, opsonic, and phlogistic functions. The amount of the complement in the milk of healthy glands of dairy cows is low. Moreover, the classical pathway of activation is not functional because of a shortage in C1q. By contrast, the alternative pathway is active, deposits C3b and C3bi on bacteria, and generates amounts of C5a which are highly variable among cows. A slight inhibition of the bactericidal/hemolytic activities, of the deposition of C1q on bacteria, and of the phlogistic activity of C5a makes milk a rather anti-inflammatory fluid. The inhibitory activity does not involve C3b/ C3bi deposition on bacteria, nor the generation of C5a by the alternative pathway. When inflammation develops, the blood-derived complement components overcome the inhibitions and complement-dependent bactericidal, opsonic and phlogistic activities may be high in milk. Further research is necessary to evaluate the contribution of C5a to the recruitment of leukocytes in the mammary gland, and to specify the links between the complement system and the response of resident cells (leukocytes and mammary epithelial cells) to infection stimulus. This will help to define the contribution of the complement system to resistance against mastitis, and could help to differentiate animals more or less resistant to this frequent and costly disease.     

山羊FSH及其长效类似物基因在小鼠乳腺中的暂态表达

应用山羊促卵泡素长效类似物基因构建其乳腺暂态表达载体pcDNAFSH-βCTP、pcDNAFSH-βCTP-α及构建报告基因pcDNAEGFP,测序后通过脂质体转染至怀孕末期的小鼠乳腺组织。结果表明,构建的乳腺暂态表达载体在小鼠乳腺中获得了表达,表达量分别为pcDNAFSHα,β(7.933±2.074)IU/L,pcDNAFSHα,-βCTP(9.311±2.995)IU/L,pcDNAFSH-βCTP-α(11.059±4.107)IU/L。     

Morphologic changes in the bovine mammary gland during involution and lactogenesis

Morphologic changes developing during bovine mammary involution were examined. Quarter biopsy specimens were obtained weekly from 5 cows beginning the day milking was discontinued through parturition. Light and electron microscopic examination of mammary tissue indicated a gradual reduction in synthetic and secretory activity of alveolar epithelium as involution progressed. Light microscopic morphologic analysis revealed increases in stroma and nonactive secretory epithelium, with concomitant decreases in epithelium, lumen, and fully active secretory epithelium during the first 2 weeks of involution. Electron microscopic analysis of alveolar epithelium revealed decreased number of organelles associated with milk synthesis and secretion during this time. These changes reversed gradually beginning 2 weeks before parturition, and by the time of calving, cell structure was typical of lactating glands. Tissue from infected quarters had less synthetic and secretory ability as indicated by significantly higher percentages of stroma and nonactive cells, but lower percentages of lumen and moderately active cells, compared with uninfected quarters. Infected quarters also had more leukocytes infiltrating the epithelium, lumen, and stroma, compared with uninfected quarters. Microscopic examination of macrophages and neutrophils suggested these cells removed milk components and cellular debris during involution. Large numbers of plasma cells, with distended cisternae of rough endoplasmic reticulum, suggested local antibody production during the periparturient period.     

Elimination kinetics of chlorhexidine in milk following intramammary infusion to stop lactation in mastitic mammary gland quarters of cows

OBJECTIVE: To evaluate the elimination kinetics of chlorhexidine in milk when used as an intramammary infusion to stop lactation in cows. DESIGN: Prospective study. ANIMALS: 6 cows. PROCEDURE: The study was performed in 2 phases. Three cows were studied in each phase. All cows were treated with chlorhexidine suspension by infusion into a mastitic mammary gland quarter after 2 milkings 24 hours apart. Foremilk samples (100 mL) were collected from treated and untreated (controls) mammary gland quarters of each cow. Chlorhexidine was extracted from raw milk, and residue concentrations were quantified by use of high-performance liquid chromatography. Foremilk samples from days 2, 5, and 8 were analyzed in phase I, and samples from time 0 and days 3, 7, 14, 21, 28, 35, and 42 were analyzed in phase II. RESULTS: In phases I and II, there was no quantifiable transference of chlorhexidine to milk in untreated mammary gland quarters. Measurable chlorhexidine residues were found in milk from treated mammary gland quarters of 2 cows throughout the 42-day sample period in phase II. Estimated mean elimination half-life for chlorhexidine in milk was 11.5 days. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of the long elimination half-life of chlorhexidine in milk from treated mammary gland quarters, the lack of human dietary exposure data to suggest a food tolerance for chlorhexidine in food products, and the Food and Drug Administration's published zero tolerance for chlorhexidine in uncooked edible calf tissues, we do not recommend extralabel use of chlorhexidine suspension as a treatment to stop lactation in mastitic mammary gland quarters of cows.     

Pathogenesis of Brucella abortus infection of the mammary gland and supramammary lymph node of the goat

Goats, both in late pregnancy and soon after parturition, were inoculated intravenously with Brucella abortus, and mammary glands and supramammary lymph nodes were examined by light and electron microscopy at 2 to 55 days post-inoculation. After 7 days, lymphoplasmacytic, histiocytic interstitial mastitis with a lobular and periductal distribution were detected microscopically. Brucellae, identified in tissues with immunoperoxidase staining and antibody-coated colloidal gold stain, were first seen in macrophages and neutrophils throughout mammary parenchyma, but most commonly in mammary alveoli. In subsequent samples, infected phagocytes progressively increased in number, especially in ductal and alveolar lumina, and adjacent parenchyma. B. abortus was in phagosomes and phagolysosomes in macrophages and neutrophils; degenerate and necrotic phagocytes were often filled with brucellae. Extracellular brucellae were associated with ruptured necrotic infected phagocytes. Supramammary lymph nodes draining infected mammary glands were enlarged. Lymphofollicular hyperplasia, medullary plasmacytosis, and sinus histiocytosis were seen microscopically. Brucellae were seen exclusively in macrophages, which were most often located in subcapsular and cortical sinuses. This study suggests that phagocytic leukocytes 1) transport brucellae into mammary glands; 2) provide a site for intracellular replication in mammary secretions; and 3) transport brucellae from mammary glands to supramammary lymph nodes.     

Pathological changes in the lungs and mammary glands of sheep and their relationship with maedi-visna infection.

Maedi-visna, a multisystemic disease of adult sheep, was first described in Spain in 1984. To get an idea of the seroprevalence of the disease locally and to estimate the number of seropositive animals with lesions, samples of blood, lungs and mammary glands were taken from 124 randomly selected sheep killed in the main slaughterhouse of Zaragoza. In the agar gel immunodiffusion test, 74 (59.7 per cent) of the sheep were positive and 50 were negative. Among the 74 seropositive animals, 19 (25.6 per cent) had no lesions in any organ, 12 (16.2 per cent) had lesions in the lungs only, 15 (20.2 per cent) had lesions in the mammary glands and 28 (37.8 per cent) had lesions in both organs. In the lungs hyperplasia of lymphoid follicles was more evident than an interstitial infiltrate but in the mammary glands this relationship was not observed. Even when the lesions occurred in both organs, they did not show the expected proportion in terms of either type or severity. Among the 50 seronegative sheep, eight (16 per cent) showed maedi-like lesions, formed exclusively by the hyperplasia of lymphoid follicles.     

Viral expression and leukocyte adhesion after in vitro infection of goat mammary gland cells with caprine arthritis-encephalitis virus

A characteristic lesion in goats infected by the lentivirus CAEV is mastitis with lymphoid hyperplasia. In order to investigate the mechanism of lesion formation, cultures highly enriched in microvascular endothelial cells, mature and immature luminal epithelial cells, fibroblasts and myoepithelial cells were established from goat mammary gland biopsies. Their susceptibility to in vitro infection with two distinct types of CAEV was investigated by PCR, antigen expression and cytopathy. The capacity of infected mammary gland cells to bind uninfected caprine leukocytes was determined by flow cytometry. All cell types tested were susceptible to CAEV infection in vitro, with different levels of sensitivity according to cell phenotype. Our results suggest that the limited extent of natural infection of mammary gland cells reflects a protective local immune response, and that the myoepithelial cell could act as a reservoir cell. After infection, the mature luminal cell acquires the capacity to bind leukocytes in vitro, which could indicate a facilitation of cellular interactions. The distinct reactions of the different cell types to CAEV infection may be correlated with events leading to progressive lesion development during the natural infection.     

Colostral and milk insulin-like growth factors and related substances: mammary gland and neonatal (intestinal and systemic) targets

The identification of hormones and regulatory factors in colostrum and milk has led to intensive investigations on their roles in the development and maintenance of the mammary and neonatal tissues. Insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) in transgenic mice influence mammary biology gland towards the end of lactation. In the bovine, IGFBP-3 is the major IGFBP in mammary secretions. In addition to binding IGFs, IGFBP-3 also binds to lactoferrin (Lf). Secreted IGFBP-3 re-enters mammary epithelial cells and with the presence of a nuclear localization sequence, IGFBP-3 and Lf enter the nucleus. Nuclear IGFBP-3 affects apoptotic signaling through the retinoic-x-receptors, while Lf affects apoptotic events through unknown mechanisms. Such interactions likely influence mammary development and involution. Furthermore, ingested colostral bioactive factors can exert regulatory functions in neonates. Intestinal receptors for IGFs and insulin are modified by age and/or diet. Feeding IGF-I had no effect, but colostrum extracts had small intestinal effects (stimulation of proliferation and villus size), suggesting that several factors, rather than one single bioactive factor were responsible. Systemic changes of metabolic and endocrine profiles in neonates depend on composition, amounts, time and duration of feeding colostrum. Early postnatal colostrum intake is not only important for the provision and absorption of immunoglobulins. Thus, in neonatal calves the lack of colostrum intake during the first 24h after birth results in a low immunoglobulin G, beta-carotene and Vitamin A status that persists for weeks and plasma patterns of fatty acids, essential amino acids and the glutamine/glutamate ratios are affected. In calves oral administration of IGF-I had no and feeding of colostrum whey extracts had only minor effects on metabolic and endocrine traits. Thus, mammary secretions influence regulatory functions of mammary and neonatal tissues.     

Immune cell differentiation in mammary gland tissues and milk of cows chronically infected with Staphylococcus aureus

This study identifies and compares the distribution of mononuclear cells in the mammary gland tissues and milk of healthy and chronically infected with Staphylococcus aureus cows. Somatic cell counts (SCCs) during the 3 months before the study were > 1 x 10(6) cell/ml in the infected quarters and < 1 x 10(5) cell/ml in the infection-free quarters. Immediately after slaughter, samples from the tissues above the gland cistern and supra-mammary lymph node were collected. No histological differences were found between the supra-mammary lymph nodes of the healthy and infected udders, and both appeared normal. In the milk of the healthy infection-free mammary glands, SCC was < 50,000 cells/ml) while epithelial cells were the predominant type. The percentage of CD18+ was low than 45%, of which over three-quarters were polymorphonuclear (PMN), and less than one- quarter were mononuclear cells. The later comprised CD4+ or CD8+ T-lymphocytes, macrophages (Mo) but not B-cells. In the tissues, there were few CD18+ leukocytes, and most of the cells were T-lymphocytes. The number of B-lymphocytes bearing CD21+ was similar to that of CD8+ and were localized in the connective tissue as clusters of 2-5 cells, mainly in areas with no alveoli, or as single cell having a dendritic like form. The number of Mos was negligible. In the milk of the infected glands, SCC exceeded 700,000 cells/ml, of which > 95% were CD18+ positive. The distribution of the leukocytes had two patterns: one presented (> 80%) of PMN cells and a small number of mononuclear cells; the second had less than 50% PMN and many mononuclear cells. The CD8+ cells in these infected sections were observed throughout the mammary epithelial cells (MEc) around the alveoli and in the alveolar lumen (AL). The numbers and the location of CD21+ B-lymphocytes were similar to those in the infection-free mammary glands. The number of CD5+ positive cells was lower than T and B- cells combined and were located throughout the mammary epithelial cells, around the alveoli and within the connective tissue. Mo numbers were high in most of those infected quarters, and were localized around the connective tissue and within the AL.     

Pharmacokinetics of fluconazole following intravenous and oral administration and body fluid concentrations of fluconazole following repeated oral dosing in horses

OBJECTIVE: To determine the pharmacokinetics of fluconazole in horses. ANIMALS: 6 clinically normal adult horses. PROCEDURE: Fluconazole (10 mg/kg of body weight) was administered intravenously or orally with 2 weeks between treatments. Plasma fluconazole concentrations were determined prior to and 10, 20, 30, 40, and 60 minutes and 2, 4, 6, 8, 10, 12, 24, 36, 48, 60, and 72 hours after administration. A long-term oral dosing regimen was designed in which all horses received a loading dose of fluconazole (14 mg/kg) followed by 5 mg/kg every 24 hours for 10 days. Fluconazole concentrations were determined in aqueous humor, plasma, CSF, synovial fluid, and urine after administration of the final dose. RESULTS: Mean (+/- SD) apparent volume of distribution of fluconazole at steady state was 1.21+/-0.01 L/kg. Systemic availability and time to maximum plasma concentration following oral administration were 101.24+/-27.50% and 1.97+/-1.68 hours, respectively. Maximum plasma concentrations and terminal half-lives after IV and oral administration were similar. Plasma, CSF, synovial fluid, aqueous humor, and urine concentrations of fluconazole after long-term oral administration of fluconazole were 30.50+/-23.88, 14.99+/-1.86, 14.19+/-5.07, 11.39+/-2.83, and 56.99+/-32.87 microg/ml, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Bioavailability of fluconazole was high after oral administration to horses. Long-term oral administration maintained plasma and body fluid concentrations of fluconazole above the mean inhibitory concentration (8.0 mg/ml) reported for fungal pathogens in horses. Fluconazole may be an appropriate agent for treatment of fungal infections in horses.