Observation Of Flunixin Meglumine Alleviating Delivery Stress In Dairy Cows During Postpartum Period

The delivery stress is the specific or nonspecific physiological and behavior response occurring during the delivery process of cows close to calving. Delivery is a painful process accompanied by acute pain. At the onset of delivery, the regular uterine contraction causes labor pains, which stimulate the stress respose of the body. Delivery stress is the risk factor of many postpartum diseases. However,in clinical practice thereare few reports about the pain and stress in the process of cows’ delivery. The objective of current study was to explose the validity and feasibility of relieving the delivery stress of cows by using a kind of analgesic called flunixin meglumine (FM).For current study, 5 multiparous cows which are healthy, have normal body condition, give birth to 2 to 5 fetus, undergo spontaneous delivery and do not have diseases within 21 days after delivery were selected. Their antepartum and postpartum caudal vein blood samples were collected respectively and conducted transcriptome sequencing (RNA-seq), thus obtaining the antepartum and postpartum differential expression genes, and verified them with qPCR. The results demonstrated that the gene HSP90a and gene PI3Kr2 related to the stress were up regulated and I3K/AKT and JNK signal transduction pathways related to the stress have been activated, which showed the occurrence of stress response during the delivery process.For further confirmation of the study, 10 multiparous cows which are healthy, have normal body condition, give birth to 2 to 5 fetus, undergo spontaneous delivery and do not have diseases within 21 days after delivery were selected. Collected their caudal vein blood samples during the period from 7:30 a.m. to 8:00 a.m. at each day of the 7 days before and after delivery respectively to and after their delivery to detect the change level of Cortisol, MDA, TAOC, T-SOD, HSP90, HSP72 and some microelements including Zn, Cu, Se and Mg in serum. The data showed significant increase of MDA,HSP90, TAOC and T-SOD (P <0.05) and decrease of Zn and Mg (P <0.05) after multiparous cows,which further proved that existence of delivery stress during the delivery process and oxidative stress injury also occurred.To clarify that the acute pain during delivery is the important inducing factor of delivery stress, the study carried out a postpartum analgesia test. 20 multiparous cows which are healthy, have normal body condition, give birth to 2 to 5 fetus, undergo spontaneous delivery and do not have diseases were selected randomly and divided into the control group and the treatment group (inject FM after delivery,2mg/kg, once a day and last for 3 days). Collected the caudal vein blood samples within 1 to 4 days after delivery to detect the content of Cortisol, MDA, HSP90, TAOC, T-SOD and microelements including Zn, Cu, Se and Mg. The results demonstrated the injection of FM after delivery decrease the content of Cortisol, MDA, Zn, Cu, Se and Mg in serum and enhanced the antioxidant ability of the antioxidant system TAOC and T-SOD. These findings demonstrated that the painwas the inducing factor of delivery stress; postpartum analgesia could relieve the stress and enhanced the antioxidant ability of the body.To explain the influence of postpartum injection of flunixin meglumine on the blood biochemical indexes and productivity of cows, 50 multiparous cows which are healthy, have normal body condition,give birth to 2 to 5 fetus, undergo spontaneous delivery and do not have diseases were selected randomly and divided into the control group and the treatment group (inject flunixin meglumine after delivery, 2mg/kg, once a day and last for 3 days). Then the caudal vein blood samples were collected within 7 days after delivery in order to detect the content of calcium, phosphorus, glucose andβ-hydroxybutyrate. The milk samples were collected 20 days after delivery in order to detect the proportion of somatic cell count and milk ingredients, and the daily milk yield and the occurrence of postpartum diseases among cows were tracked and recorded. The results showed the injection of flunixin meglumine after delivery could cause an extremely significant improvement of postpartum hypoglycemia in cows (P <0.01). The application of this medicine was also observed to increase the daily average milk production of 21 days and of 90 days to 2.14 kg (P >0.05) and 2.90kg (P >0.05),separately. Additionally, the morbidity of mastitis decreased 8% among cows (P>0.05). However, these differences were not significant.To further discuss the influence of flunixin meglumine on the morbidity of postpartum diseases among cows, the test conducted the data related to the morbidity of mastitis, displacement of abomasum,lameness, ketosis, diarrhea and metritis before and after using the FM on cows in a dairy farm. It depicted that the morbidity of mastitis declined from 41.87% to 35.22% (P <0.05) after injecting FM.Meanwhile, the similar effect was also presented in abomasum displacement and lameness, which morbidity was decreased respectively from 10.42% to 8.19% (P<0.05) and from 27.10% to 22.45% (P<0.05), separately.Findings of current study showed that, stress response exists in cows’ delivery process, the pain in cows’ delivery process is one cause of the stress response, the injection of FM after delivery can effectively relieve the delivery stress and decrease the morbidity of mastitis, displacement of abomasum and lameness among cows.