Factors affecting the differential epithelial cell count in preputial cytology of healthy intact dogs

Information is limited on the factors that may affect the preputial differential epithelial cell count in healthy intact dogs. Our objectives were to establish RIs of the preputial differential epithelial cell count in dogs and investigate the potential impact of signalment, presence of gross preputial discharge or neutrophils, preputial cleaning, and normal estrogen variation on the differential cell count. We enrolled prospectively 50 client-owned, healthy dogs in our study. Preputial cytology smears were obtained, and we performed a 4-part (parabasal, intermediate, superficial, cornified) differential cell count, before and after gentle preputial cleaning. We found higher counts of fully cornified cells (median: 11-12%) compared to previous studies. The cleaning procedure significantly decreased the intermediate (p = 0.002) and increased the superficial (p = 0.006) cells. Age was positively associated with intermediate (p = 0.007) and negatively with superficial (p = 0.01) and cornified (p = 0.02) cells. The concentration of estrogens was negatively associated with the percentage of parabasal cells (p = 0.04). In healthy dogs, a variable impact may be expected in the preputial differential epithelial cell count, by the cleaning of the prepuce before sampling, the age of the dogs, and the normal variation of estrogen concentration.

The effect of the stage of the ovarian cycle (anoestrus or dioestrus) and of pregnancy on the incidence of gastro-oesophageal reflux in dogs undergoing ovariohysterectomy

OBJECTIVE

To investigate the potential association of increased blood progesterone (P4 ) concentrations and/or late pregnancy with the incidence of gastro-oesophageal reflux (GOR), in healthy bitches undergoing ovariohysterectomy under general anaesthesia during anoestrus or dioestrus or during the second half of pregnancy.

STUDY DESIGN

Prospective observational study.

ANIMALS

Ninety-four healthy, female, dogs, aged 1-8 years presented for elective ovariohysterectomy.

METHODS

Non-pregnant animals were classified into group A (anoestrus) (n = 35) if blood P4 concentration was sufficiently low or group D (dioestrus) (n = 26) if blood P4 concentration was sufficiently high. All animals in the second half of pregnancy were classified into group P (n = 33). Acepromazine (0.05 mg kg(-1) ) was administered intramuscularly as preanaesthetic medication, and sodium thiopental (10 mg kg(-1) , with additional doses if needed) was administered intravenously (IV) for induction of anaesthesia. After endotracheal intubation, halothane (1.1-1.3% end-tidal concentration) in oxygen was used for maintenance of anaesthesia. Lower oesophageal pH was monitored continuously throughout surgery using a pH-measuring probe. Reflux was considered to have occurred whenever pH values of >7.5 (alkaline reflux) or <4 (acid reflux) were recorded. On completion of surgery, carprofen (4 mg kg(-1) ) was administered IV. Further administration of analgesics post-operatively was dictated by visual analogue scale pain scoring.

RESULT

Acid GOR was observed in five of 26 dogs in group D, six of 35 group A, and 12 of 33 group P (p = 0.152). The incidence of GOR in group P approached statistical significance and was higher than the incidence in the combined group A + D (one sided p = 0.044, two sided p = 0.077).

CONCLUSIONS

In dogs undergoing ovariohysterectomy, GOR during anaesthesia occurs with a high incidence in dogs in the second half of pregnancy compared to non-pregnant animals during anoestrus or dioestrus.

CLINICAL RELEVANCE

Measures could be taken in such cases to avoid the consequences of potential reflux.

Histological features in the mammary glands of female dogs throughout lactation

The objective of this study was to describe the histology of the mammary glands of female dogs throughout lactation. Twelve lactating female dogs were operated 4, 7, 10, 14, 21, 28, 35, 42, 56, 70 and 84 days post-partum; four mammary glands of each animal were excised for histological, ultrastructural and morphometric examination. During early lactation and mid-lactation, all lobes and lobules within the same gland had similar features; alveoli were well developed and distended and had a spherical to slightly ovoid structure, with muscular fibres grasping them around; inflammatory cells were seen in the inter- and intra-alveolar space; mammary lobules were separated with a scant amount of connective tissue. In late lactation, connective tissue was abundant and dense, with large numbers of inflammatory cells; alveoli appeared to be irregularly shaped and collapsing, shrunken or fully collapsed. Number of alveoli per lobule and number of epithelial cells per alveolus, as well as diameter of alveoli and height of epithelial cells decreased as lactation progressed. The third mammary glands (from caudal to cranial) had a significantly smaller number of alveoli, but not of epithelial cells per alveolus, than each of the two mammary glands caudally to that. The results suggest that progressive involution of the normal mammary gland starts around the end of the 2nd month of lactation and continues until the end of the 3rd month.

Anesthesia and Perioperative Management of a Pneumonectomized Dog

Although left- or right-sided pneumonectomy is tolerated by normal dogs, complications impacting the respiratory, cardiovascular, and gastrointestinal systems are not uncommon. Pneumonectomy in dogs results in secondary changes in the remaining lung, which include: decreased compliance and vital capacity; and increased pulmonary vascular resistance potentially leading to right ventricular hypertrophy. Such alterations make the anesthetic management of an animal with one lung particularly challenging. This report describes a dog with a history of left pneumonectomy due to Aspergillus fumigatus pneumonia 3 yr before presentation. The dog presented with a vaginal wall prolapse, and surgical resection of the protruding vaginal wall, ovariectomy, and prophylactic gastropexy were performed. Anesthesia was induced with midazolam, fentanyl, and propofol and was maintained with isoflurane using intermittent positive pressure ventilation and a constant rate infusion of fentanyl. Epidural anesthesia was also used. Recovery and postoperative management were uncomplicated. Intensive hemodynamic and respiratory monitoring and appropriate response and treatment of any detected abnormalities, taking into consideration the pathophysiologic alterations occurring in a pneumonectomized animal, are required for successful perianesthetic management.

Experimental staphylococcal mastitis in bitches: clinical, bacteriological, cytological, haematological and pathological features

The objectives of the work were to study the features of experimentally induced canine mastitis and to present hypotheses regarding the pathogenesis of the disease. The right caudal abdominal mammary gland of six bitches was inoculated on day 8 after whelping with Staphylococcus intermedius to induce mastitis; adjacent mammary glands were used as controls. Clinical examination, bacteriological and cytological (whiteside test, Giemsa) examination of mammary secretion, as well as haematological tests were performed from 5 days before until 34 days after challenge. Mastectomy was sequentially performed 1, 2, 4, 18, 26 and 34 days after challenge in each of the bitches, in order to carry out a pathological examination of mammary glands. All animals developed clinical mastitis: challenged glands became painful, hot, enlarged and oedematous; secretion was brownish, purulent, with flakes or clots, subsequently becoming yellowish and thick. Staphylococci were isolated from all inoculated glands (up to 22 days). WST was positive in 41/46 samples from inoculated glands and 66/138 samples from control glands; neutrophils predominated during the acute stage. Blood leukocyte counts increased, whilst platelet counts decreased. Gross pathological findings initially included congestion, purulent discharge and subcutaneous oedema; then abscesses, brownish areas and size decrease were seen. Salient histopathological features were initially neutrophilic infiltration, haemorrhages, destruction of mammary epithelial cells and alveoli, and then infiltration by lymphocytes, shrunken alveoli, loss of glandular architecture and fibrous tissue proliferation. We conclude that in bitches, intrammamary inoculation of Staphylococcus intermedius can induce clinical mastitis, followed by subclinical disease. The disorder is characterized by bacterial isolation and leukocyte influx in challenged glands, by leukocyte presence in adjacent mammary glands, by increased blood leukocyte counts and by destruction of mammary parenchyma.

Serum estradiol-17β, progesterone and respective uterine cytosol receptor concentrations in bitches with spontaneous pyometra

The role of serum estradiol-17 beta (E(2)) and progesterone (P(4)) in relation to uterine estrogen (ER) and progesterone receptors (PR) was investigated in canine cystic endometrial hyperplasia-pyometra (CEH-P). Blood and uterine samples were collected pre- and post-ovariohysterectomy, respectively, from 54 bitches presenting spontaneous CEH-P and 25 healthy control bitches. Competitive enzyme immunoassays (EIA) and enzyme ligand immunoassays (ELIA) were applied to estimate serum hormones and uterine cytosol active receptors, respectively. Animals were classified in the stages of first half of diestrus, second half of diestrus and early anestrus on the basis of reproductive history, clinical signs, uterine and ovarian macro- and microscopic inspection and serum P(4) concentration. Bitches with CEH-P, compared to their respective stage controls, exhibited (a) similar P(4) fluctuations, (b) higher E(2) concentrations, (c) lower PR concentrations during diestrus first and second half and (d) lower ER concentrations during diestrus first half and early anestrus. Negative correlation was detected between P(4) and ER within both CEH-P and control groups. It was concluded that P(4) was the main uterine receptor regulator for both PR and ER during diestrus and early anestrus in healthy and affected uteri. However, in CEH-P bitches, high P(4) levels in diestrus appeared to over-activate uterine PRs, leading to stronger PR self-down regulation and ER suppression. These findings indicate an increased sensitivity of CEH-P uterus to P(4) action. During early anestrus, a complementary role of endogenous E(2) was considered, since reduction of P(4) action appeared to permit uterine ER replenishment and activation by relatively high E(2) levels.

A comparison between ethanol-induced chemical ablation and ivermectin plus prednizolone in the treatment of symptomatic esophageal spirocercosis in the dog: a prospective study on 14 natural cases

This study included a total of 14 dogs with spontaneous esophageal spirocercosis. Historical and clinical evidence of esophageal dysphagia, detection of parasitic ova in fecal samples and endoscopic documentation of esophageal nodules were the inclusion criteria. The animals were randomly assigned into two groups: group A (n = 6 ) dogs received two intranodular injections of absolute ethanol (96%) via a through-the-endoscope injector, at weekly intervals; group B (n = 8) dogs were put on ivermectin (600 microg/kg BW, subcutaneously, twice, 14 days apart) and oral prednisolone (0.5mg/kg BW, every 12h, for a total of 3 weeks, tapering the dose accordingly). Clinical and fecal examination as well as endoscopy, were performed on admission and at 20, 60 and 180 days from the beginning of the treatment. One group A dog responded poorly and died of pyothorax during the trial and another developed esophagitis due to accidental intraluminal ethanol infusion, only to experience an uneventful recovery. At different times during the 6-month follow-up period, there was a complete disappearance of the clinical signs in 4/6 group A dogs. However, full nodular regression was achieved only in one dog, and parasitic ova were still found in the feces of 4/6 dogs. At the same period of time in five group B dogs still available for evaluation, resolution of the clinical signs and complete nodular regression were seen in four and five animals, respectively, while negative fecal results were obtained in all dogs (8/8) of the same group 2 months from the beginning of the treatment. No significant difference was found between the groups, regarding the resolution of clinical signs, though group B dogs demonstrated a significantly higher rate of regression of esophageal nodules as well as negative fecal results, compared to group A dogs. The combination of ivermectin and prednizolone may be considered an effective treatment in the symptomatic and evidently asymptomatic esophageal spirocercosis of the dog.

Use of enzyme-immunoassay for oestradiol-17beta and progesterone quantification in canine serum

The objective of this investigation was to develop and evaluate competitive inhibition-enzyme-immunoassays for canine serum oestradiol-17beta (E(2)) and progesterone (P(4)) quantification. Sera from 56 healthy bitches at various stages of oestrus cycle and pregnancy were tested. For E(2) measurement, each sample (0.4 ml) was extracted with diethyl ether and after solvent evaporation the resultant hormone was reconstituted to one-fifth of the original sample volume in aqueous buffer. Each reconstitute (30 microl) was assayed for E(2) to estimate respective serum concentration. For P(4), each sample (10 microl) was directly assayed without extraction. The classic cyclic hormonal pattern during the oestrus cycle of the bitch was observed. The brief, sharp dominance of E(2) during the follicular phase was followed by the long-lasting dominance of P(4) during the luteal phase (late oestrus, dioestrus or pregnancy). During the anoestrus phase both hormones were found at basal levels, with the exception of E(2) during late anoestrus which appeared to be rising. Both assays had acceptable specificity (cross-reactions < or =10%), precision (coefficient of variation (C.V.) < 7%) and accuracy (E(2) recovery: 97%; P(4) recovery: 104.7%). The sensitivity of E(2) and P(4) assay was 4 pgml(-1) and 0.28 ngml(-1), respectively.