Background

Dogs develop spontaneous ischaemic stroke with a clinical picture closely resembling human ischaemic stroke patients. Animal stroke models have been developed, but it has proved difficult to translate results obtained from such models into successful therapeutic strategies in human stroke patients. In order to face this apparent translational gap within stroke research, dogs with ischaemic stroke constitute an opportunity to study the neuropathology of ischaemic stroke in an animal species.

Case presentation

A 7 years and 8 months old female neutered Rottweiler dog suffered a middle cerebral artery infarct and was euthanized 3 days after onset of neurological signs. The brain was subjected to histopathology and immunohistochemistry. Neuropathological changes were characterised by a pan-necrotic infarct surrounded by peri-infarct injured neurons and reactive microglia/macrophages and astrocytes.

Conclusions

The neuropathological changes reported in the present study were similar to findings in human patients with ischaemic stroke. The dog with spontaneous ischaemic stroke is of interest as a complementary spontaneous animal model for further neuropathological studies.

Intoxication due to short-term oxyquinoline therapy was studied in 100 dogs, which had been so treated because of diarrhoea (except in 2 cases). The latter condition was in itself mild and uncomplicated. The main symptoms of intoxication were listlessness or excitation and nervousness, aggressiveness, tremor, convulsions, and salivation. Clinical examination revealed myocarditis and liver injury. Mortality, i.e. the sum of spontaneous deaths and euthanasia, amounted to 30 %. The treatment considered to be most important was sedation and anticonvulsant measures. It was further essential to correct the dehydration, which was often present. A follow-up investigation showed that approx. 1/3 of the dogs which had recovered from the acute intoxication developed recurrent convulsions within the next 3 years.

Weekly blood samples were collected for serum progesterone determination from 68 mares during the period from September 1990 to June 1991. A total of 78% (53/68) of the mares became anoestrous: 88% (15/17) of mares with foals and 75% (38/51) of dry mares (p = 0.323). Six mares of the 15 which continued cycling showed persistent corpus luteum for 77 days on average (range 42-106 days). Anoestrus began between September and February, most frequently in December, and ended in January to June, most frequently in March. Mares with foal at foot became anoestrous in 2 separate groups, in September and in December. Anoestrus ended most frequently in February in foaled mares. The mares with foals differed significantly from the other mares both at onset (p = 0.0084) and end (p = 0.0218) of anoestrus.

However, the effect of the stable was also significant at onset (p = 0.0386) and end (p = 0.0170) of anoestrus. Since all mares with foals were kept in one stable and dry mares in 4 different stables, the effect of stable and possible differing lighting conditions cannot be separated from the foal effect. The length of anoestrus was on average 101 days for lactating mares and 95 days for dry mares (p = 0.6691). In foaled mares its length was on average 159 days in mares which had entered anoestrus as early as in September-October and 62 days in mares entering anoestrus in December (p = 0.001). The effects of breed and age were not significant in any of the parameters.

Fifty-six tied heifers calving in autumn (trial I) and 21 tied heifers calving in late spring (trial II) were fed either a high or a low concentrate diet from 3 weeks before expected calving until 13 weeks after calving. Half the heifers in trial I were kept on concrete floors and the others were kept on rubber mats; all the heifers in trial II were on concrete floors. The hooves were trimmed and the soles were photographed 3 weeks before expected calving and again 13 weeks after calving. The photographs were evaluated, each claw was scored for sole haemorrhages, and the total score for all 8 claws was calculated. Before calving there were no differences between the groups of heifers within trial I or trial II, but the heifers in trial II had higher scores than those in trial I. Thirteen weeks after calving the scores had increased in both trials. In trial I the animals fed the high concentrate diet and kept on concrete floors had the highest score, and the type of floor had a greater influence than the level of concentrates fed. The heifers calving in the autumn had higher scores than those calving in the spring. The sudden change from being at pasture to being housed, and the events related to the periparturient period were the most significant factors for the development of sole haemorrhages.

Background

Horses may acquire a range of paranasal sinus diseases. Clinical studies show slight differences regarding anatomical regions and age. Histopathological examination of tissue samples could play an important role in the diagnostic process. Therefore, detailed knowledge of the histological appearance of the paranasal sinus mucosa (PSM) and the nasomaxillary aperture mucosa (NAM) is essential. The objective of this study was to determine topographic and age-related differences within the healthy equine PSM. In addition, we aimed to gain detailed knowledge of the histological appearance of the NAM in comparison to the PSM.

Results

The PSM had an average height of 75.72 ± 44.48 μm with a two-row pseudostratified columnar epithelium of 13.52 ± 4.78 μm. The parameters mucosal height, epithelial height and number of goblet cells revealed significant dependency of the sample site and age group. The maxillary and dorsal conchal sinus showed the highest values for these parameters. In terms of age, younger horses showed a significantly higher total mucosal height in contrast to a significantly lower epithelial height than older horses. Positive correlation was seen between the epithelial height and number of goblet cells. The NAM had an average height of 820.27 ± 653.21 μm. Its pseudostratified epithelium was usually arranged in three rows and had an average height of 44.9 ± 12.78 μm. The number of goblet cells in the NAM was five times higher than in the PSM. Serous glands were found in only 4% of the PSM samples and 100% of the NAM samples.

Conclusions

There are significant histological differences between different paranasal sinus sites and between different groups of age. This may be related to an altered susceptibility for certain pathologies. The striking difference in the histological appearance of the NAM compared to the PSM could be due to an enhanced role in mucociliary clearance. Further studies are necessary to improve the understanding of mucosal function in specific paranasal sinus compartments and mucosal changes generated by different diseases.

The article reviews methods used for in vitro evaluation of sperm, with particular emphasis on frozen-thawed stallion sperm. The techniques, limitations of the methods and correlations with fertility results are discussed. Very few studies have tried to find correlation between fertility of frozen stallion semen and laboratory tests. It is difficult and expensive to inseminate an adequate number of mares to achieve statistically significant differences. Significant, but low correlations have been demonstrated between the foaling rate and subjective motility of sperm incubated for 2 h and 4 h at 37°C and hypoosmotic swelling test after 0 and 3 h of incubation. Significant correlations have been reported between the pregnancy rate and viability of propidium iodide-stained sperm assessed by flow cytometry as well as for glass wool and Sephadex filtration tests. No correlations have been detected between fertility and motility immediately after thawing. In spite of that, motility estimation by light microscope is the most commonly used method to evaluate frozen-thawed stallion sperm. Computer assisted automatic sperm analyzers have replaced light microscopy in research projects, but so far nobody has been able to demonstrate a correlation between fertility of frozen stallion semen and any of the motility parameters obtained by these instruments.

Sera were tested in 2 series both by the conventional technique (dilution in tubes) and by the microtiter system. In 1 series of comparative examinations the tests were performed with the same batch of accessory factor serum and antigen preparation, and in another series the tests were performed at 2 different laboratories. There was a high correlation between the 2 methods, but the titres obtained by the microtiter system were about 1 to 2 twofold dilutions lower than those obtained by the conventional dilution technique. The 95 % confidence limits by the microtiter system were plus and minus 1 twofold dilution.

Summary

The present paper is the continuation of a previously published work, (Havre & al., 1960), on the study on conditioned and simple copper deficiency in cattle and sheep in Setesdalen, a valley in the South of Norway.

In order to verify molybdenum as a conditioning factor, the fluctuations of the content of molybdenum and copper in the grass during the summer season 1959 have been studied. It was found that the content of both molybdenum and copper increased during the summer and reached its highest values in the first part of August. As stated in the previous paper, the conditioned copper deficiency in Setesdalen was proved to be a disorder occurring on autumnal pasture.

From the clinical material collected during the years 1958–60, it may be concluded that the simple copper deficiency in Setesdalen occurs only in the winter season, on stallfeeding. This corresponds fairly well with the fact that the copper content of the herbage has its lowest value about the first of July, the time for grass-mowing in Setesdalen.

The seasonal variations of copper and molybdenum were compared with statistics of the precipitation in the investigated areas in the same summer. The content of molybdenum as well as copper in grass was found to be lower in 1959 than in the previous years, probably due to the dry summer in 1959. The molybdenum figures, however, are still above 3 p.p.m. in herbage from areas with conditioned copper deficiency, and the copper figures below 5 p.p.m. in areas with simple copper deficiency. These concentrations were in the first work, in accordance with Cunningham, stated as the “dangerous” limits.

In the present work, spectrographs analyses of a series of elements, altogether 18, are carried out on grass samples collected in the summer of 1959. The etiological importance of the various elements is discussed and particular attention is paid to sodium, manganese and sulphur. Sulphur is treated more thoroughly, as the whole herbage material from 1958 has been analysed on total as well as on inorganic sulphur (sulphate), in order to study Dick’s theory on sulphur as a conditioning factor in the syndrome of conditioned copper deficiency. The results of the analyses, however, give no support for sulphur as a conditioning factor in Setesdalen.

A hypothetical “copper favouring factor”, possibly vitamin A, is discussed.

The clinical observations are discussed in relation to the analytical results.

Summary

In a herd of standard minks 30 cases of leucoencephalopathy were demonstrated in the mink kits in the years 1962 and 1963. The disease is assumed to be hereditary and due to a sub-lethal, recessive, autosomal factor. A comparison with the forms of diffuse sclerosis found in man demonstrated that the disease, as it appeared in minks, bore a striking resemblance to the so-called metachromatic type of leucoencephalopathy.

Semen samples were collected from 21 Danish Warmblood stallions by the Colorado artificial vagina (Colorado AV, 14 samples) or by the Missouri artificial vagina (Missouri AV, 7 samples). The semen was examined bacteriologically by direct plating (DP) on blood agar plates, and by plating of semen swabs stored in Stuart’s transport media (TM) at 4°C for 1–4 days. No significant differences were observed between results obtained by DP and cultures of identical TM samples. Of the 21 samples examined, only 1 TM (4.8%) and 2 DP samples (9.5%) were sterile, while the rest yielded a predominantly mixed flora comprising 1 to 4 bacterial genera. The natural flora was dominated by coagulase-negative staphylococci (Staphylococcus lentus, S. capitis, S. haemolyticus, S. xylosus) (16/21 = 76%), coryneforms (11/21 = 52%) and alpha-hemolytic streptococci and lactobacilli (7/21 = 33%). Potential venereal pathogens were isolated from 7 stallions (33%). Beta-hemolytic streptococci were found in 4 stallions used for natural service, whereas Pseudomonas aeruginosa serotype 6 (2 samples ) and Klebsiella pneumoniae subsp. pneumoniae capsule type K5 (1 sample) were isolated from 3 stallions used exclusively for artificial insemination. The role of the stallion as a carrier of potential venereal pathogens, and the artificial vagina as a source of contamination, is discussed in the context of mare endometritis.