Effects Of Pain Management On Behavior,Nutrition Metabolism And Production Performance Of Dairy Cow After A Difficult Calving

Parturition is a necessary event for production in dairy cattle,and is also a strong stressor.The sharp pain is the core reason of labor stress,and is often worse as dystocia happens,which will lead to persistent and chronic pain,and then affect the health and production performance of dairy cows.The objective of this study was to determine the effect of a new generation nonsteroidal anti-inflammatory drug——Meloxicam on behavior,dry matter intake,production performance,physical condition,health events,ruminal fermentation and nutrition digestion,as well as blood biochemical index,and consequently to explore the effects of Meloxicam on primiparous cows and multiparous cows as well as the mechnisms involved.The main details and results are as follows:1)Effect of pain management on behaviors of dairy cows after a difficult calving.Holstein cows(n = 120)including primiparous cows(n=58)and multiparous cows(n=62),that experienced middle and severe dystocia from Sino farm were chosen as experimental animal.These animals were divided into control group and treatment group randomly,which received 15 mL normal saline and 15 mL Meloxicam 1 hour following calving,respectively.Behaviors,such as lying,standing,feeding,ruminating,drinking,tail raising and rubing were observed.The results indicated that after injecting Meloxicam 3 days following calving,for promiparous cows,time spent lying and standing increased significantly,yet time spent walking and drinking,tail raising and rubbing frenquency were not influenced significantly;while for multiparous cows,time spent lying increased significantly,time spent drinking tail raising and rubbing frenquency reduced significantly,and standing time were not influnced.In addition,ruminant behavior recovery of both primiparous cows and multiparous cows was not affected.Estimating from the point of behavior,injecting Meloxicam 1 hour following dystocia alleviated labor pain of both primiparous cows and multiparous cows to some extent.2)Effect of pain management on health events and production performance of dairy cows after a difficult calving.Experimental animals were chosen and treated identically with 1).Dry matter intake(DMI),physical condition and health events of all experimental animals were observed and recorded.Ten primiparous cows and ten multiparous cows were chosen randomly from the control group and the treatment group,respectively.Milk somatic cell count(SCC),protein,lactose,fat and urea nitrogen contents were measured following 3 days of dystocia.The results indicated that Meloxicam significantly reduced SCC in colostrum of both primiparous cows and multiparous cows,and the incidence rate of mastitis and sub-clinical ketosis,while had no significant effect on DMI,milk yield and composition of milk,as well as body condition score.In addition,Meloxicam reduced incidence rate of displacement of abomasum(DA)and fore-stomach stony of both primiparous cows and multiparous cows,and rudeced incidence rate of hoof disease and culling rate of primiparous cows.However,Meloxicam had no effect on incedence rate of hoof disease for multiparous cows and retained fetal membranes for primiparous cows.3)Effect of pain management on blood biochemical index of dairy cows after a difficult calving.Experimental animals were chosen and treated identically with 1),and ten primiparous cows and ten multiparous cows were chosen randomly from control group and treatment group,respectively.At 0,12,24 and 48 h after injection,blood samples were collected from the tail vein into 10 mL evacuated tubes,and concentration of tumor necrosis factor –α(TNF-α),serum amyloid protein A(SAA)and haptoglobin(HP),as well as cortisol and prostaglandin(PG)were tested.The results indicated that Meloxicam promoted decline of TNF-α,SAA and HP level significantly,and inhibited the synthese of cortisol and PG,relived dystocia pain,inflammatory response and labor stress of primiparous cows to some extent,and had no or non-significant effect on multiparous cows.4)Effect of pain management on ruminal fermentation and apparent digestibility of dairy cows after a difficult calving.Experimental animals were chosen and treated identically with 1),and 5 primiparous cows and 5 multiparous cows were chosen randomly from control group and treatment group,respectively.At 1 day and 4 day after parturation,the rumen contents were collected approximately 3~4 h after the morning feeding by the oral stomach tube method.Ruminal pH,NH3-N,and VFA concentrations were tested.Fecal grab samples were collected for 3 consecutive days after parturition from each animal.The content of dry matter(DM)、Ash、crude protein(CP)、neutral detergent fiber(NDF)and acid detergent fiber(ADF)were measured,and then the apparent total tract digestibility of these nutrients was calculated by using AIA as an internal standard.The results indicated that Meloxicam had no significant effect on acectic acid : propionic acid and pH value of rumen fluid,prometed the hydrolysis of protein and increased the concentration of NH3-N(P>0.05),increased concentrations of acetic acid and propionic acid significantly and butyrate acid nonsignificantly at 1 d after parturation.In addition,Meloxicam increased the concentration of total VFAs for promiparous cows,and promoting the increasing of the total VFAs for multiparous cows,and so fermentation efficiency of cows after a difficlut calving was improved.Meloxicam effectively improved mutrition apparent digestibility of both primiparous cows and multiparous cows.For primiparous cows,apparent digestibility of NDF,ADF,DM and CP was improved 32.19%,28.64%,25.71% and 9.3%,respectively.For multiparous cows,apparent digestibility of NDF,ADF,DM and CP was improved 12.5%、14.25%、30.9%和 10.36%,respectively.In conclusion,through promoting decline of serum TNF-α,SAA and HP concentration,and inhibiting synthese of cortisol and PG,Meloxicam could inhibite incidence or promote elimination of inflammation after dystocia,and relieve labor pain of primiparous cows to some extent.And then affect behavior,physical condition,ruminal fermentation and nutrition digestibility.Even more,specific to primiparous cows,the effect of Meloxicam was better.It is noteworthy that Meloxicam had no effect on some indexes,such as,dry matter intake,milk yield and composition,body condition et al..It is neccessary to carry on more researches to reveal such result.