I followed the discussion as Helen, the farm manager, explained to my attachment students how to profitably manage a mixed livestock farm of pigs and dairy cattle.
I was accompanied by three of the five veterinary students attached to my practice. The farm is located in Gatundu, Kiambu County and Helen, the manager, is also a veterinary paraprofessional.
She had called to report five weaner piglets that were looking unwell. Four of the piglets had loose faeces and poor appetite. The fifth pig had swollen eyelids and part of the face tissues around the eyes, giving it a puffy appearance.
On receiving the call, I immediately instructed Helen to give the four less sickly pigs antibiotics and anti-inflammatory injections immediately. Later, she was to follow with antibiotics in water for three days.
The very sick piglet was to be given the same injections, get isolated from the others and be kept warm. The piglet was also to be given antibiotics directly by mouth for three days.
The farm has about 300 pigs of different ages and Helen has managed to keep most diseases under strict control. I only visit the farm when she has issues beyond her scope.
In many cases, I make diagnosis on the phone from her reports and advise her on the course of treatment. This strategy has been effective in disease control and in the reduction of the cost of production attributed to provision of veterinary services.
“So, vets in the oven, what is your diagnosis of this disease?” I asked the veterinary students as Helen completed giving them the history of the disease occurrence in the five piglets.
They responded in unison “gut oedema”. I was impressed with their confident response. “You guys are baking well,” I congratulated them. I assured the students if they continued with that trend, they would definitely qualify as veterinary doctors next year.
I listened with content as the students narrated to me the case history, the disease, how it is spread and its presentation in sick pigs.
They concluded by explaining how the disease is diagnosed, treated and prevented. My assessment was that the students had impressively improved since they came for their two-month attachment in January this year.
Satisfied with the way Helen had handled the gut oedema case and the students’ performance, I instructed the manager to take the students on a tour of the farm and I would deal with any questions that were beyond her scope.
Gut oedema affects mainly weaner pigs from one to four weeks post weaning. In some cases, healthy pigs will die suddenly without showing any signs of disease.
The disease is also called bowel oedema or oedema disease. Oedema is the swelling caused by accumulation of body fluids in tissues.
The disease is caused by some types of infective Escherichia coli (E. coli) bacteria that infect the pig intestines. The name of the disease comes from the swelling found at post-mortem in the intestinal and stomach walls.
E. coli bacteria infects the pigs from the pen environment. Weaning stress, change of diet and increased feeding after weaning are known factors that contribute to establishment of the infection.
Once in the intestines, the bacteria produce a very potent toxin that destroys the small blood vessels of the intestines and stomach causing leakage of fluid into the tissues, and hence the swelling.
The bacterial toxin is also absorbed into the blood stream and distributed to all body organs, where it destroys more small blood vessels and causes swelling.
Some of the other signs of the disease that are observed in cases that do not die suddenly are associated with the effects of the toxin in body organs.
Toxin reaching the brain causes swelling resulting in unstable gait, staggering and incoordination of the legs. Some pigs may be unable to stand due to paralysis.
There is swelling of the eyelids and facial tissues resulting in the puffy-face appearance of the pigs. In some cases the eyelids swell and completely shut.
In the early stages of the puffy face, the piglets look drowsy or alcohol-drunk. A farmer once told me her pigs appeared intoxicated and she suspected the worker had given them alcohol to keep them quiet when he was late in feeding them.
Some pigs may have loose faeces or diarrhoea in the early stage of the infection before the bacteria produces sufficient toxin to cause the full blown disease.
HEAVY ECONOMIC LOSSES
Such pigs should be quickly treated with antibiotics to arrest the infection and halt toxin production.
Gut oedema is difficult to treat because the effects of the toxins in the late stages of the disease are not reversible.
Further, there is no way of knowing how much toxin the bacteria may produce. This is the reason why some pigs just die suddenly.
However, diligent observation within the first four weeks of weaning and treatment with antibiotics at the onset of loose faeces or diarrhoea help in preventing further progression of the disease.
In Helen’s case, four piglets out of five were saved by early detection and treatment. Pigs that show mild to serious disease take two to three weeks to recover but most of the pigs detected in late stages of the disease die even with treatment.
Gut oedema also causes heavy economic losses because pigs with mild to serious disease grow much slower than other pigs and they mature up to four weeks later than their age mates.
Prevention of gut oedema is the best strategy of controlling the disease. This is done by ensuring very high levels of hygiene thorough cleaning and disinfection of the pig pens. In addition, some pig lines appear to be genetically susceptible to the disease.
Farmers should avoid breeding sows whose piglets consistently get gut oedema.
Pigs weaned at 5 to 8 weeks of age tend to be affected more by the disease. I advise farmers to lower the weaning age to 17-26 days if they have access to high quality pig starter feed.
Alternatively, they can lower the weaning age to between 26 and 30 days.