CASE NOTES
Sand Impaction Causing Weight Loss and Mortality in Angus Bulls
Rebecca Densely, Bordertown and Keith Veterinary Clinics,19 Woolshed Street, Bordertown, South Australia and Jeremy Rogers, Senior Veterinary Officer, Biosecurity Division, Primary Industries and Regions SA - PIRSA, Government of South Australia,Bremer Rd, Murray Bridge
Posted Flock & Herd October 2019
Introduction
Sand impaction has been reported when cattle have been fed silage containing large amounts of sand and in cattle bedded on sand (Erickson and Hendrick, 2011). In Australia the condition is seen in droughts when livestock consume soil and sand either as they attempt to graze in bare paddocks or when they are hand fed on sandy soil.
This report describes a case of sand impaction that occurred in bulls that were hand fed in a sandy lot.
History
Seven of 28 three-year-old Angus bulls run in a sandy feedlot died in the first two weeks of May 2015. The summer and autumn had been very dry and May was unusually cold resulting in minimum pasture availability. The bulls were therefore handfed for longer than usual. The area where the bulls were kept was very sandy with no obvious poisonous plants seen. The bulls were being fed lucerne chaff and haylage (oats and lucerne) and good quality bore water.
Bulls are bred on a property in the Adelaide Hills and transferred to this property at approximately 18 months of age, prior to mating in June each year. The bulls are then kept on the Willalooka property.
Clinical findings
Following the death of another two bulls, the mob was examined on 15 May 2015. The two dead bulls were somewhat bloated with blood coming from the rectum. There was evidence of diarrhoea prior to death and about 30% of the other bulls in the group also appeared to have evidence of scouring and were in poor condition. Salmonellosis was initially suspected. Copper poisoning was also considered as copper sulphate is added to the bulls' water supply.
One affected bull seen in the paddock became aggressive when yarded and was unable to be examined. This bull had watery diarrhoea, appeared dull when undisturbed and was bloated.
It was recommended that the bulls be treated with a single injection of long acting oxytetracycline and moved to a bigger paddock. No further deaths were observed in this group for one week with affected bulls appearing to improve.
A second mob of 40 three-year-old bulls was examined on 19 May 2015 when bulls from this mob were seen to be affected, and there was concern that the disease was "spreading". These bulls were being fed crushed barley in addition to lucerne chaff and silage from the same source as the previously affected bulls.
One of these bulls was found to be bloated with watery diarrhoea, an elevated heart rate and a subnormal temperature. This bull became recumbent with grunting and groaning and was euthanased and a post-mortem conducted (case 1).
Another mob of young bulls being fed the same ration in nearby paddocks were unaffected.
The bulls were again examined on 3 June 2015 when a bull that had previously been affected but appeared to respond to antibiotics developed a bloody scour and appeared very depressed. This bull was shot and also necropsied (case 2). Other affected bulls were observed to be bloated, dull, with evidence of weight loss and watery diarrhoea and then found dead in most cases. A third bull from this group presented as dull, with evidence of watery scour, T 37.4°C and rumen fluid in nostrils, mouth and pharynx. One bull was observed to vomit before death.
Necropsy findings
In case 1 necropsied on 19 May 2015, peracute peritonitis with a ruptured abomasum containing a large amount of fine sand was found. However, suspicion remained that this case may have been different to other bulls and an infectious cause was still suspected.
Three bulls were necropsied on 3 June 2015. The first was in advanced decomposition but the second and third bulls had large amounts of fine sand in the abomasum. In one bull there was approximately 10kgs of fine sand in the abomasum that was packed hard and an estimated 20kgs in the rumen, reticulum and omasum. The abomasum appeared irritated and there was no food material in the intestinal tract that had signs of irritation (see figure 7).
Figure 1. Four year old bull affected by sand impaction (from another property).
Figure 2. Bull with watery diarrhoea
Figure 3. Evidence of regurgitation
Figure 4. Bull with no fat reserves
Figure 5. Impacted abomasum
Figure 6. Sand in the abomasum
Figure 7. Abomasal inflammation presumably from sand irritation.
Laboratory Findings
Little pathology of significance was seen in the numerous fresh and fixed samples submitted for examination. Cultures were negative for Salmonella and Yersinia. Copper levels in blood and liver samples of tested animals were within normal limits.
Discussion
Sand impaction is rarely described in cattle but may be a more common cause of death and morbidity than previously thought, particularly where hungry animals are being hand fed in very sandy conditions for a considerable period. Anecdotal reports from this area are that there have been other mortalities due to sand impaction in cattle recently, but there are few reports in the Australian literature about sand impaction in cattle.
Treatment of sand impaction is problematic, and would include dosing with paraffin oil, antibiotic cover and perhaps Epsom salts. Management changes where sand impaction may occur might include feeding hay and silage on a hard pad or rubber matting (conveyor belt), salt supplementation to increase water intake in cold weather and treatment of affected animals.
Reference
- Erickson N and Hendrick S (2011). Sand impactions in a Saskatchewan beef cow-calf herd. Can. Vet. J. 2011 Jan; 52(1): 74-76