Prevalence and potential risk factors of hypocalcaemia in dairy cows during transition period at Northern Egypt

Abstract

Objective: To identify the most prevalent diseases of transition period in dairy cows and to highlight on risk factors supposed to play a crucial role in the prevalence of hypocalcaemia. Design: Case-control study Animals: 179 transition dairy cows belonged to five farms. Procedures: Clinical examination and serum analyses were the key to diagnose the transition disorders in the investigated cows. Cutoff points for serum analytes (Ca, Ph, Mg, PTH, glucose, K, Na and Cl) were set. A questionnaire was constructed to identify the possible risk factors associated with hypocalcaemia on both farm level and cow level. Results: Frequency test revealed the prevalence of hypocalcaemia to be (48.04%), hypophosphatemia (40.22%), hypomagnesaemia (33.52%) hypoglycemia (29.05%), hypokalemia (58.1%), clinical ketosis (5.59%) and abomasal displacement (1.12%). Moreover, prevalence of post parturient septic metritis was (26.81%), retained placenta (23.46%) and clinical mastitis was (18.99%). Generally, hypocalcaemia was significantly associated with other concurrent diseases (P ≤ 0.05). Levels of serum PTH, glucose, K and Na were significantly related to occurrence of hypocalcaemia with p values: 0.006, 0.001, 0.019 and 0.001, respectively. Impact of diet, housing criteria and periodical health monitoring by metabolic profile test were found to affect significantly on incidence of hypocalcaemia on farm level with p value ≤ 0.008 for all. On cow level, age of cows, parity, body condition score, stage of transition period, daily milk yield and previous transition period disorders were found to have a significant effect on occurrence of hypocalcaemia at p value ≤ 0.001 for each item. Conclusion and clinical relevance: Results of the current study point toward the importance of usual monitoring of transition period disorders in dairy cows, besides identifying potential risks and consequences of hypocalcaemia in an attempt to construct control measures for them, that in-turn would increase dairy herd profitability.