Concentrations of protein, glucose, fructose and ions in the flushings of the oviducts and uteri of erhualian and meishan sows

Flushings of oviducts and uterine horns from Chinese Meishan (MS, n = 11), Erhualian (EH, n = 13) and Large White x Meishan crossbred sows (LM, n = 5) aged 34-56 months were collected at different phases of the oestrous cycle and analysed for the concentrations of total protein, glucose, fructose and Mg++, Fe+++, Na+, Zn++, K+, Cu++, Mn+++ and Co++ ions. The results showed that, in oviductal flushings, the average concentration of protein was higher in MS than in EH (p < 0.1) and in LM of the same phases of the cycle (p < 0.05). The oviductal levels of glucose on day 4 in EH and on day 10 both in MS and EH were significantly higher than in LM (p < 0.05 or < 0.01), while there were no differences in fructose levels between breeds and stages of the cycle. In the uterine flushings, the concentrations of protein and fructose were not different between breeds or phases of the cycle, but glucose level in LM was lower than in Meishan on day 4 (p < 0.05) and lower than in EH both on day 4 and day 10 (p < 0.1 and < 0.05, respectively). Oviductal and uterine protein in MS and EH and uterine glucose in EH increased steadily from day 0 to 10 of the oestrous cycle, and then declined to their lowest levels on day 16 of the cycle. No significant within-breed changes in the concentration of fructose were observed during the cycle. Glucose concentration in the oviductal flushings of MS and EH showed high variations at the different phases of the cycle. The average concentrations of Fe+++ and Cu++ ions in the oviductal flushings were significantly higher in Meishan than in Erhuallian and crossbred sows at identical phases of the oestrous cycle (p < 0.01 or < 0.05), while K+ level was lower in Meishan (p < 0.05) and Erhualian sows (p < 0.1) than in crossbred sows of the same stage of the cycle. In uterine flushings of crossbred sows, K+ and Co++ levels were higher and Fe+++ level was lower than in the other breeds at corresponding phases of the cycle (p < 0.05 or < 0.1). There were no differences in other ions between the breeds in either flushing. No typical patterns of ionic secretions were discernible.