Study On The Correlation Between Abnormal Behavior Of Holstein Cows And Their Milk Performance And Physiological Indices

Under intensive feeding conditions,abnormal behaviors of dairy cows frequently occur,which often indicates the poor welfare of animals.However,it is not clear whether the occurrence of abnormal behavior will further affect the animals themselves,and the causes and physiological mechanisms of their occurrence are yet to be explored.This paper investigates the specific circumstance of abnormal behaviors in Holstein cows on intensive scale farms and correlates it with production performance and physiological and biochemical indices,from which the effects of abnormal behavior on cows and potential mechanisms of occurrence are explored with a view to providing a basis for fine-tuned management of cows.The paper consists of the following experiments:Experiment 1: Investigation on the Abnormal Behavior of Holstein Cows in Large-scale FarmsBehavior observation experiments were carried out on five large-scale dairy farms with similar feeding management and feeding methods.Three herds of weaned calves,growing cow,and lactating cow were selected for observation in each cattle farm.Using the slice observation method,each herd was regularly observed eight times a day for three consecutive days.The abnormal behaviors of dairy cows were recorded and counted.The results showed that: 1)The incidence of citta,excessive grooming,cross grooming,cough,and cross sucking in weaned calves was significantly higher than that in growing cows(P<0.01),and that in growing cows was significantly higher than that in lactating cows(P<0.01);The incidence of tongue rolling and scratching in weaned calves was not significantly different from that in growing cows(P>0.05),but it was significantly higher than that in lactating cows(P<0.01).2)The diurnal fluctuation range of incidence of abnormal oral behavior in weaning calves was significantly greater than that of growing cows(P<0.05),and that of growing cows was significantly greater than that of lactating cows(P>0.05).The incidence of tongue rolling of Holstein cows during feeding decreased significantly compared with that before and after feeding(P<0.05),and the incidence of excessive grooming did not differ significantly compared with that before and after feeding(P<0.05),but had an upward trend(P=0.08).In conclusion,the incidence of abnormal behaviors in Holstein dairy cows and their daily fluctuation range are significantly reduced from weaning calves,growing cows to lactating cows,and both of them are affected by feeding.Experiment 2: Analysis of the Correlation between the Abnormal Behaviors and Milk Production Performance of Holstein CowsBased on Experiment 1,we select four dairy farms that have accurate milk production performance data.During the observation period,the lactating cows’ daily milk production was recorded for three days,and individual DHI data of the observed herds were obtained for subsequent statistical analysis.SAS 9.4 software GLM process was used to analyze the correlation between Holstein cow’s milk production performance and its abnormal behaviors.The fixed model was used to consider the influence of farms,lactation period,parity,thermal environment,abnormal behaviors,and other factors.The results showed that cows’ daily milk yield with tongue rolling behavior was significantly higher than that of cows without tongue rolling behavior(P<0.05).The milk fat and milk protein percentage of cows with excessive grooming were significantly higher than that of cows without excessive grooming behaviors(P<0.05).The milk protein percentage of cows with excessive scratching behavior was significantly higher than that of cows without excessive scratching behavior(P <0.05).Overall,with the increase in the frequency of cows’ abnormal behaviors,the milk production performance showed a trend to increase and then decrease.It is concluded that modest abnormal behaviors can relieve the cow’s stress response,thereby improving milk production performance.However,when abnormal behaviors occur frequently,milk production performance will decline,indicating that the cows’ health was affected.Experiment 3: Analysis of differences in behavior,gut microbes,and physiological and biochemical indices between tongue rolling weaned calves and non-tongue rolling weaned calvesBased on the investigation,the dairy farm with the highest incidence was selected,and the weaned calves(5 months old)raised in the same enclosure were observed for 7 consecutive days,including 6hours of observation per day,and 3 slicing observations per hour.The frequency of abnormal behavior of the calves and the corresponding ear tag number were recorded.Fifteen healthy weaned calves with the highest frequency of tongue rolling or no abnormal behavior were selected respectively,then video was performed,and blood samples,fecal samples,and saliva were collected for analysis.The results showed that the frequency of tongue rolling was significantly and positively correlated with the frequency of drinking(P<0.05),and there was a trend of positive correlation between the duration of drinking and the frequency of eating.The levels of Ig A,TNF-α,IL-6,and IL-10 in the blood of the weaned calves in tongue rolling group were significantly lower than those in non-tongue rolling group,and the levels of NE,E,DA,HSP-70,LD,and CK in tongue rolling group were significantly lower than those in non-tongue rolling group.There were significant differences in Alpha diversity ace index and coverage index between the two groups,and there were also significant differences in the flora and structure of fecal microflora between the two groups.Calves in tongue rolling group showed a decrease in the proportion of the Firmicutes and an increase in the proportion of Bacteroidota and were significantly enriched in o＿Coriobacteriales,o＿Saccharimonadales,f＿Atopobacteriaceae,and g＿Olsenella,while non-tongue rolling calves were significantly enriched in o＿Bifidobacteria and c＿Actinomycetes.In conclusion,calves are able to release stress by expressing tongue rolling behavior and have lower levels of stress hormones compared to calves that do not express tongue rolling behavior.The gut microbial alpha diversity and flora structure are significantly different between tongue rolling calves and non-tongue rolling calves,and some bacteria can be used as potential biomarkers.