Comparison of uterine protein content and distribution of bacteria in the reproductive tract of mares after intrauterine inoculation of Haemophilus equigenitalis or Pseudomonas aeruginosa.

This research investigated the effects of intrauterine infection with two types of bacteria, Haemophilus equigenitalis and Pseudomonas aeruginosa, in mares. It studied the protein content and bacterial distribution in the reproductive tract after such infections, and found varying results for the different bacterial species, whilst also identifying an effective method of isolating H. equigenitalis.

Experimental Procedure

• The study involved two groups of three mares. The first group was inoculated with Haemophilus equigenitalis and the second group with Pseudomonas aeruginosa. The inoculation process occurred on the first day of estrus.
• Uterine flushing samples, which involved the use of a particular solution to cleanse the uterus, were obtained on the third day of estrus and the eighth day after ovulation for each cycle.
• Following infection, the mares were euthanized after differing periods of time, dependent on the bacteria with which they were inoculated. Mares with P. aeruginosa were killed between 22 and 30 days later and mares with H. equigenitalis were killed between 45 and 49 days later.

Results of the Study

• Pseudomonas aeruginosa was recovered from the uterine samples of two mares 48 hours after inoculation. Notably, while the initial sample from one of these mares showed increased total protein concentration, the protein concentrations of other uterine samples didn’t appear to differ significantly.
• The H. equigenitalis bacteria was found in the uterus of all three of the corresponding group mares at post-mortem. One mare from this group had slight purulent (pus-introducing) discharge from the vulva. This mare did not show any increase in total protein values in uterine flushing samples after the infection.
• In the case of the remaining two mares infected with H. equigenitalis, total protein values actually decreased in the last flushing sample.

Method of Isolation of Haemophilus Equigenitalis

• The study found that swabbing the uterine mucosa was a more effective method for isolating the Haemophilus equigenitalis bacteria, as compared to the process of homogenizing the uterine mucosa.

In conclusion, this research advanced understanding of intrauterine infections in mares due to different bacterial species, demonstrating the resultant effects on uterus protein content and bacterial distribution. It also elucidated a more successful method to isolate Haemophilus equigenitalis from the mare’s uterus.