Decreasing the proportion of apoptotic cells in the endometrium in early period of involution in hyperketonaemic cows.

In a recent study 49 cows were sampled via endometrium biopsy during the early puerperium on day 4 to 14 to determine the apoptosis index Blood samples were taken simultaneously for BHB analysis According to the histological evaluation of the biopsy tests, many samples (n=25) were excluded from the later evaluation because of degradation or missing epithelium Paraffin-embedded tissue samples were immunofluorescence stained for apoptosis (nuclear fragmentation) detection, terminal deoxynucleotidyl-transferase mediated dUTP nick-end labelling (TUNEL) Leukocytes were stained with fluorescent anti-CD45 antybody to separate them from endometrium cells Nuclei were counterstained with fluorescence DAPI The apoptotic index was calculated by dividing the total number of apoptotic endometrial cells by the total number of endometritial cells and multiplying by 100 According to their uterine status and plasma BHB content, the cows were classified as (i) controls (n=10), (ii) normoketonaemic-endometntic (n=9) furthermore (iii) hyperketonaemic (BHB 1 00 mmol/l) individuals with or without puerperal endometritis (n=5) The apoptosis index of controls (BHB 045 +/- 0,12 mmol/l), normoketonaemic-endometntic cows (BHB 0 42 +/- 0,15 mmol/l) and hyperketonaemic animals (1 47 +/- 0,32 mmol/l) was 50 +/- 6%, 52 +/- 1% and 24 +/- 6%, respectively The apoptotic indexes of normo- or hyperketonaemic animals show significant difference It was concluded that hyperketonaemia related to the postpartum negative energy balance in dairy cows decreases the occurrence of energy-requiring apoptosis in the involution of endometrium, increasing the risk of necrotic degeneration of epithelial cells and the consequent inflammatory complications