Evaluation of blood metabolites reflects presence or absence of liver abscesses in beef cattle
During this summary the topic of liver abscesses in beef cows, cost to the industry and animal welfare will all be discussed. Results will be given on an experiment that was undertook to determine whether there is a safer and more accurate way to illustrate whether a cow has present liver abscesses during the last few days before slaughter and any present abscesses at the abattoir. This was achieved by examining different components that make up the cow’s blood and liver bile to see if any would give evidence of liver abscesses or liver damage. Being able to detect liver abscesses quickly and accurately are crucial for; saving the beef industry large sums of money a year, avoiding potentially contaminated meat or organs from entering the food chain, and improving farming animal welfare. The hypothesis of this study is that blood and bile components will contrast between cows with normal and abscessed livers.
To determine whether blood and bile components have the potential to suggest indication of liver abscesses, a variation in several parameters were examined. These included; metabolic hormones, indicators of hepatic and whole-body metabolism and sexual hormones and ions. The presence or absence of liver abscesses served as the arrangement criteria for two groups which the bulls would be placed into. Results for this experiment are noted as abscessed bulls being compared with normal bulls.
Table 1 shows the results of the observations of the blood parameters taken over the nine sampling events taken from all the bulls before slaughter. There is a significant decrease in levels of albumin, cholesterol and testosterone in bulls with abscessed livers, as well as an increased concentration of cortisol and aspartate aminotransferase (AST) in abscessed bulls compared to normal bulls. Table 2 describes the results of the blood tests taken at the abattoir. The bulls that did have liver abscesses showed signs of low levels of thyroxine, albumin, alkaline phosphates (ALP) cholesterol and glucose. Abscessed livers in bulls were also seen to be associated with lower biliary cortisol and lower levels of blood carbon dioxide.
The results from the experiment suggest that a variation in the several blood parameters that were observed prior to slaughter and of the day of slaughter could be clear indicators of present liver abscesses in bulls. There is a clear divide in variation of blood parameters of bulls that had normal livers and those who had abscessed livers. Lower levels of albumin were found in the blood of abscessed bulls before slaughter. Albumin is an abundant serum protein synthesised by the liver. Low levels of albumin are associated with damage to the liver, therefore the bulls that had liver abscesses would have expressed low levels of albumin as the health of their liver would have been compromised by the abscesses. This is important as it can now be seen that albumin levels can be used as one of the several accurate indicators of liver disease or damage.
Table 1 Results of blood parameter observations between abscessed and normal bulls before slaughter.
|Abscessed (n=9)||Normal (n=20)|
Table 2 Results of blood parameter observations between abscessed and normal bulls at the abattoir.
|Abscessed (n=9)||Normal (n=20)|
It is to be noted that differences in the blood taken from the bulls before slaughter and the bulls at the abattoir could differ due stress bought on by transportation, noises, sights and smells from the abattoir. The results of this experiment highlight the importance of accurate blood analysis to indicate liver abscesses. Early indication is beneficial for the beef industry for a variety of reasons; it enables an increase in efficacy of cattle management, helps to prevent liver abscesses from developing in other heard members by changing factors of husbandry and management in comparison to the already infected cows and finally it increases food safety and hygiene as premature warning of liver abscesses prevent infected organs or meat from being obtained by abattoirs.
Macdonald, A. G. C., Bourgon, S. L., Palme, R., Miller, S. P. and Montanholi, Y. R. (2017) ‘Evaluation of blood metabolites reflects presence or absence of liver abscesses in beef cattle.’ Veterinary Record Open, 4(1) p. e000170.