The comparative evaluation of uterine and cervical mucosa cytology with endometrial histopathology in cows

Chronic inflammatory and degenerative endometrial lesions in subfertile Criollo Limonero cattle; a B. taurus Latin-American breed threatened with extinction; A case-control study

Criollo Limonero is a tropical Bos taurus breed for sustainable dual purpose (milk and beef) production in the South-American tropics, which is currently threatened with extinction. The objective was to perform a clinical evaluation and histopathological assessment of uterine biopsy samples of repeat breeder (RB) Criollo Limonero cattle to determine the occurrence of pathological conditions as potential causes of subfertility. Twenty-four Criollo Limonero cattle [18 cows (5-13 years old) and 6 heifers (6-7.5 years old)] that had failed to conceive after four or more services were considered for this study. Additionally, five cows with history of adequate reproductive performance were used as a control group. Animals were submitted to physical exam, vaginoscopy, and ultrasonographical evaluation of the reproductive tract. Uterine biopsy samples were collected for histopathological evaluation. Vaginoscopy revealed that 41.7% of the RB cattle had abnormal vaginal secretions, while abnormal secretions were not observed in any control cow. Ultrasonographical examination of the uterus revealed the presence of free uterine fluid in 20.8% of the RB animals, while none of the control cows had fluid in the uterine lumen. In addition, ovarian cysts were observed in 25.0% of the RB animals. Histopathological evaluation of the endometrial biopsies revealed that mononuclear leukocyte infiltration, dilated uterine glands, and periglandular fibrosis were the most prevalent lesions in the sub-fertile animals. Chronic endometritis characterized by inflammatory (mononuclear leukocyte infiltration) and degenerative (dilated glands and periglandular fibrosis) endometrial lesions, and ovarian cysts were the most frequent reproductive pathologies observed in the studied subfertile Criollo Limonero cattle, suggesting a strong association with their reduced fertility.

Characterization of inflammatory responses by cervical cytology, cytokine expression and ultrastructure changes in a goat subclinical endometritis model

Endometritis is a common puerperal disease in livestock. Thus, a practical clinical test for the establishment of diagnosis is needed. We developed a goat model for subclinical endometritis diagnosis by examining cytological, ultrastructural features and molecular expression in cervical discharge collected by cervical cytobrush method. A suspension of E. coli was infused into the uterine horn of goats, and cervical discharge, peripheral blood and endomertrial biopsy samples were collected before inoculation and at 3, 6, 12, 24, 72, 120 and 168 hr post-inoculation (pi). In experimental goats, total leukocytes increased at 6-12 hr pi in hematological examinations, abundant neutrophils were observed in cervical discharge smears, and some micro-villi shortened or were lost from the epithelium at 3 hr pi, with some inflammatory cells infiltrated into the uterine glands and lamina propria. The mRNA expression levels of the Toll-like receptor 4 (TLR4), cytokines and β-defensin-2 increased significantly within 12 hr pi and returned to pre-inoculation levels at 7 day pi. The results showed that subclinical endometritis was simulated in this bacterial infusion goat model, and the evaluation of cervical cytology was in good agreement with molecular changes of cytokines in cervical discharge, hematology and histology. We thus conclude that the simple cervical cytobrush technique can effectively obtain cervical discharge samples for cytology examination in the early diagnosis of subclinical endometritis in goats.

Evaluation of endometrial echotexture and cervical cytology in cows during and after treatment of endometritis

OBJECTIVE

The aim of this study was to evaluate changes in the endometrium by using echotexture parameters during and after treatment of endometritis with intrauterine administration of an intrauterine antiseptic solution (Lotagen®, 3% metacresolsulphonic acid and formaldehyde) in cows which became pregnant after treatment.

MATERIAL AND METHODS

According to the severity of endometritis 21 cows were divided into three groups: E1 (slight, n = 7), E2 (moderate, n = 8), E3 (severe, n = 6). The control group (C, n = 11) consisted of cows without endometritis that did not receive an intrauterine medication. A software (Bs200 Pro®) was used to evaluate echotexture parameters Contrast (CON), Gradient (GR), Homogeneity (HOM), Mean Gray Level (MGL) of images taken during the examinations at hours (h) 0, 1 and 6 and days (d) 2, 3, 5 and 10.

RESULTS

At 0 h, GR was significantly lower in group E2 than in groups E1 and C (p < 0.05). There was an increase in GR values between 0 h and 10 d in group E2 and E3, but a decrease during the same time interval in group C (p < 0.05). In contrast, CON values of group E2 were lower (p < 0.05) at 0 h compared to other timepoints of examination and lower than in group C. HOM values were lower (p < 0.05) in groups E1, E2 and E3 than in group C on d 5 and d 10. HOM values were higher at 1 h compared to 6 h, d 2 and d 10 in group E3 (p < 0.05). By contrast to GR values, HOM values were higher in group C at 6 h and d 10 than they were in group E3. MGL values of group E2 were higher (p < 0.05) than in group C until d 10 and higher (p < 0.05) in group E3 than in group C at 6 h after treatment. In group E2 an increase of MGL values until d 2 was followed by a decrease (p < 0.05).

CONCLUSION

Echotexture parameters determined by the evaluation of sonographic B-mode images reflect changes in the endometrium and could be used for the evaluation of the recovery period after treatment of endometritis.

Comparison of a leukocyte esterase test with endometrial cytology for diagnosis of subclinical endometritis in postpartum dairy cows

The objective was to compare a leukocyte esterase (LE) test with endometrial cytology (EC) for diagnosis of subclinical endometritis in dairy cows. The relationship between subsequent fertility and the uterine (Ut) and cervical (Cx) leukocyte esterase activity was determined by the odds of pregnancy by 90 days in milk (DIM). Holstein cows (N = 218) without clinical endometritis and between 21 and 47 DIM from five commercial dairy herds were sampled for uterine and cervical leukocyte esterase activity and EC by cytobrush. To test the effect of time, cows were grouped into early (21-31 DIM) and late (32-47 DIM) animals. There was a slight agreement between UtLE and CxLE (weighted κ = 0.37). The percentage of neutrophils was correlated with esterase score either from the uterus (UtLE; P = 0.0001) or cervix (CxLE; P = 0.002). The percentage of neutrophils on EC (P < 0.001), the UtLE score (P < 0.0001), and the CxLE (P = 0.0009) diminished as DIM increased. Neither CxLE nor UtLE were statistically associated with pregnancy at 90 DIM. However, between 32 and 47 DIM, the percentage of neutrophils on EC and odds of pregnancy at 90 DIM were associated (P = 0.04). For the same interval, based on receiver/response operating characteristics analysis, the optimal cutoff was >6.7% neutrophils to classify cows with subclinical endometritis. In conclusion, uterine LE activity was correlated with percentage of neutrophils as determined by EC, but not with odds of pregnancy. Subclinical endometritis (>6.70% neutrophils) diagnosed by EC between 32 and 47 DIM was associated with reduced odds of pregnancy.