The current study aimed to assess the effects of non-genetic parameters (stage lactation, parity order, and gender of calving) on the persistence of milk production in crossbred. The study was carried out on twenty-eight crossbreed dairy cows in the fields of the University of Khartoum educational farm under unified administrative and nutritional conditions. The cows were in different production parity orders for milk (the second season to the seven season) and physiological status. The results showed that the persistence in milk production was good in the early (99.82%) and midem (93.54%) lactation stages, the percentage of persistence peaked in the second month (102.14%). In addition, this may be attributed to the use of bulls with high breeding values for milk yield. The parity order of crossbred cows had a significant (P<0.05) effect in months two and three The highest lactation persistency (162.67 and 115.20%) was observed in primiparous cows, compared to the multiparous, which reached (140.32 and 111.86%), respectively. The calving of the gender of crossbred cows had a significant (P<0.05) effect in months two and third in the persistency of milk production, the highest lactation persistency (168.93 and 131.98%) was observed in cows giving birth to males, compared to the cows giving birth to females, which reached (126.24 and 117.72%). respectively. For optimal milk production and efficiency, cows with high lactation persistence are preferred.

Highlights

• The percentage of persistence peaked in the second month.
• The parity of crossbred cows had a significant effect in months two and three.
• The highest lactation persistency was in primiparous cows compared to the multiparous.