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1.
The function of the immune system was studied in 34 bitches affected by pyometra. The mean age of the animals was 8.1 +/- 2.8 years. Samples of peripheral blood were examined using a battery of immunological tests. Data obtained from four sets of animals, grouped according to the severity of their disease, were compared. Leucocytosis (neutrophilia and partial monocytosis) and lymphopenia were detected in 62 per cent and 35 per cent of the bitches, respectively. The increase in the number of leucocytes was higher in the severely affected bitches. Inhibition of mitogen-driven lymphocyte proliferation was the characteristic feature of the immunological profile in bitches affected by pyometra, and this corresponded with the impairment of the general state of health. Sera from bitches showing functional inhibition of lymphocytes suppressed the activity of lymphocytes isolated from normal dogs. Sera from bitches affected by pyometra also had higher levels of immunoglobulins, lysozyme and circulating immune complexes. It can be concluded that pyometra is associated with an inflammatory response, but also with a marked suppression of immune system activity.  相似文献   
2.
The phenotypic characteristics are described for the activity of polymorphonuclear leucocytes NMN) obtained by either lavage of the cavity system of juvenile mammary glands stimulated with a synthetic muramyl dipeptide analogue or isolation from the peripheral blood. Attention was paid to the variability of characteristics and its sources, and to correlations among them. The following characteristics were investigated in 27 clinically healthy, unbred Bohemian Red Pied x Holstein heifers: migration activity in situ, number of phagocytosing PMN, phagocytotic index, bactericidal activity of PMN and unstimulated and zymosan-stimulated luminol-dependent chemiluminescence. Considerable individual variation was found in the characteristics. Significant differences between blood PMN and PMN from lavages after influx induction were found for bactericidal activity (P < 0.05) and chemiluminescence (P < 0.01). A significant correlation between blood PMN and mammary gland PMN was found only for the number of phagocytosing cells (r = 0.329; P < 0.01). Highly significant positive correlations (P < 0.01) were demonstrated between the number of phagocytosing PMN [a], phagocytotic index [b], and bactericidal activity [c] in both blood PMN (r(ab) = 0.602; r(ac) = 0.565; r(bc) = 0.529) and mammary gland PMN (r(ab) = 0.730, r(ac) = 0.618, r(bc) = 0.589). No significant correlation was demonstrated for non-stimulated (NS), zymosan-stimulated (ZS), or opsonized zymosan-stimulated (OZS) chemiluminescence with any of the other characteristics of phagocytotic activity, in either blood PMN or mammary gland PMN (P > 0.05). The animal was a highly significant source of variability for all the phagocytotic activity characteristics (P < 0.01). Udder quarter was a non-significant source of variability for all the characteristics of phagocytotic activity except for NS chemiluminescence (P < 0.05) and ZS or OZS chemiluminescence (P < 0.01). However, udder quarter was a non-significant source of variability of chemiluminescence indices ZS/NS and OZS/NS (P > 0.05). It has been demonstrated that in situ migration activity, the number of phagocytosing PMN, phagocytotic index, bactericidal activity of PMN and chemiluminescence indices of PMN collected from juvenile mammary glands of unbred heifers after influx induction can be regarded as candidate early markers of resistance to mammary infections.  相似文献   
3.
Commercial serological sets were used for the examination of 727 cats kept in larger towns of the Czech Republic. FeLV antigen and antibodies to FIV were demonstrated in 96 (13.2%) and 42 (5.8%) of the animals, respectively. Seven (0.96%) animals were positive for both FeLV and FIV. Most of the FeLV and/or FIV positive patients were intact rambling males aged 1-4 years. Chronic gastrointestinal and respiratory diseases were found in 54.2% and 43.8% of the FeLV-positive patients, respectively. Chronic urinary tract diseases and generalized lymphadenopathy were found in 47.6% and 45.2% of the FIV-positive patients, respectively. The results of this first survey in the Czech Republic have shown prevalence values and clinical patterns similar to those reported formerly from other European countries.  相似文献   
4.

Background

Chronic exposure to cadmium (Cd), even at low concentrations, has an adverse impact on the skeletal system. Histologically, primary and secondary osteons as basic structural elements of compact bone can also be affected by several toxicants leading to changes in bone vascularization and mechanical properties of the bone. The current study was designed to investigate the effect of subchronic peroral exposure to Cd on femoral bone structure including histomorphometry of the osteons in adult male rats.In our study, 20 one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group, young males received a drinking water containing 30 mg of CdCl2/L, for 90 days. Ten one-month-old males without Cd intoxication served as a control group. After 90 days of daily peroral exposure, body weight, femoral weight, femoral length, cortical bone thickness and histological structure of the femora were analysed.

Results

We found that subchronic peroral application of Cd had no significant effect on body weight, femoral length and cortical bone thickness in adult rats. On the other hand, femoral weight was significantly increased (P < 0.05) in Cd-intoxicated rats. These rats also displayed different microstructure in the middle part of the compact bone where vascular canals expanded into central area of substantia compacta and supplied primary and secondary osteons. Additionally, a few resorption lacunae which are connected with an early stage of osteoporosis were identified in these individuals. Histomorphometrical evaluations showed that all variables (area, perimeter, maximum and minimum diameter) of the primary osteons’ vascular canals, Haversian canals and secondary osteons were significantly decreased (P < 0.05) in the Cd group rats. This fact points to alterations in bone vascularization.

Conclusions

Subchronic peroral exposure to Cd significantly influences femoral weight and histological structure of compact bone in adult male rats. It induces an early stage of osteoporosis and causes reduced bone vascularization. Histomorphometrical changes of primary and secondary osteons allow for the conclusion that the bone mechanical properties could be weakened in the Cd group rats. The current study significantly expands the knowledge on damaging action of Cd on the bone.  相似文献   
5.
Water, Air, &; Soil Pollution - The concentrations of some essential (Cu, Zn, Se) and some toxicelements (Hg, As) were determined in tissues (liver, kidneys, integument, and muscle) of the...  相似文献   
6.
7.
In 1986-1988, adverse anaphylactoid reactions (AR) were observed in animals in Czechoslovakia after the administration of oil adjuvant-containing vaccines or other lipoid drugs. Treated animals showed signs resembling the classic anaphylactic reaction, i.e. restlessness, salivation, pruritus, oedema and cyanosis of udder and vulva, and eyelid oedema, developing within a few minutes. The reactions were not elicited by the antigen alone, but by the oil adjuvant. The aim of our experiments was to identify substances eliciting the reaction in susceptible animals and to investigate possible induction mechanisms. The emulsifier Tween 80 has been demonstrated to be an AR inducing component of vaccines and drugs (Tab. I and III). Weak or moderate reactions were observed in 33% of animals treated with 5% Tween and 66% of those treated with 10% Tween showed strong reactions. On the other hand, no reactions were elicited by treatment with several paraffin oils of different quality (Tab. I) nor with an oil-in-water emulsion containing Montanid as an emulsifier (Tab. II). The role of the vegetative nervous system in the rise of AR has been confirmed. AR were suppressed in animals pretreated with parasympatholytic atropine and enhanced in a part of those pretreated with parasympathomimetic pilocarpine (Tab. III). The percentage of animals affected and the intensity of AR were also lower in animals pretreated with complement inhibitor epsilon-aminocapronic acid (Tab. IV). A major role of complement activation is suggested in the discussion of possible mechanisms of AR induction. It is possible to draw a conclusion on the basis of the results presented here and of the analysis of individual cases that a certain degree of animal susceptibility, depending on the phase of reproductive cycle, metabolism level and neurovegetative balance is necessary besides the administration of an AR inducer (Tween 80 in our case). Hence it seems that the adverse anaphylactoid reactions results from interactions of the two factors, i.e. administration of an AR inducer to susceptible animals.  相似文献   
8.

Background

The role of selenium (Se) on bone microarchitecture is still poorly understood. The present study aims to investigate the macroscopic and microscopic structures of femoral bone tissue in adult male rats after subchronic peroral administration of Se.

Methods

Twenty one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group (Se group) young males were exposed to 5 mg Na2SeO3/L in drinking water, for 90 days. Ten one-month-old males without Se administration served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy.

Results

The body weight, femoral length and cortical bone thickness were significantly decreased in Se group rats. These rats also displayed different microstructure in the middle part of the femur, both in medial and lateral views, where vascular canals expanded into the central area of the bone while, in control rats, these canals occurred only near the endosteal surfaces. Additionally, a smaller number of primary and secondary osteons was identified in Se group rats. Histomorphometric analyses revealed significant increases for area, perimeter, maximum and minimum diameters of primary osteons’ vascular canals but significant reductions for all measured variables of Haversian canals and secondary osteons.

Conclusions

Se negatively affected the macroscopic and microscopic structures of femoral bone tissue in adult male rats. The results contribute to the knowledge on damaging impact of Se on bone.  相似文献   
9.
10.
It is not easy to exactly diagnose the etiology of the mass infections of new-born calves on large farms where considerable losses are suffered. On the basis of the complex epizootological, clinical and laboratory examination in four large calf-rearing facilities, rotaviruses, coronaviruses, the infectious bovine rhinotracheitis (IBR) virus and the bovine viral diarrhoea (BVD) virus, and in some cases also the enteropathogenic E. coli, were found to be etiologically involved in the mass rise of diarrhoea, complicated by respiratory symptoms already during the first days after birth. The clinical picture of the disease, therapeutically difficult and reminding of "pneumoenteritis", has often been observed in stocks where, in addition to rotaviruses and coronaviruses in the faeces, the IBR or BVD viruses (sometimes both at the same time) were detected and identified in the respiratory and enteral tract. The serological examination of a higher number of animals in the stocks of calves under study confirmed the considerable rate of spreading of all the four viruses in the cattle population and, at the same time, demonstrated the very unfavourable immunological profile of the herds. The high percentage of animals low in antibody titres and the serologically negative animals constitute the infection-sensitive part of population in the affected herds. With the high culling rate and with the open herd turnover it is impossible to reach the required immunity through natural disinfection. Loss-free rearing of healthy calves will be achieved on the basis of a well-oriented vaccination programme with a good combination of inoculants.  相似文献   
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