Studies on Camel Haemonchosis Caused by Haemonchus Longistipes (Railliet and Henry, 1909) in the Sudan

Abstract

The clinico-pathological features and parasitological aspects of naturally-occurring and experimentally-induced Haemonchus longistipes infection of camels together with that induced in a co-habiting host, the goat, were studied. The infected animals were examined ante-mortem and post-mortem and jugular blood was obtained from each animal for haematological and biochemical determination. It was found that the naturally occurring disease in camel was more prevalent during the rainy season than during the dry season. Experimental H. longistipes infection in camels and goats was characterized by inappetence, weakness, diarrhoea, oedema, anaemia, loss of body weight, alopecia and pica. In both animal species, the haematological investigations indicated a decrease in RBCs number, Hb concentration and PCV; increases in WBC counts, especially the eosinophils and neutrophils while lymphocytes were very much reduced. These changes coincided with high faecal egg per gram values and the Wintrobe indices indicated presence of normochromic normocytic anaemia during the infection. The biochemical parameters determined during the infections showed increases in blood urea and blood urea nitrogen contents indicating kidney damage; this is, also confirmed by histopathological investigations. The globulin level is very much increased while the albumin level is depressed and the total serum protein level is drastically decreased during the infection. Other parameters showed decreases in serum magnesium and calcium levels of infected animals, while sodium, potassium and blood glucose concentrations showed no deviation from normality. The main pathological lesions comprised of abomasitis with erosions, haemorrhages, ulcerations and hypertrophy of the organ. Other changes included paleness and discolouration of the liver, congestion and scattered haemorrhages in the lungs, cortical tubular necrosis with patchy interstitial congestion of the kidneys, hydropericarditis and ascites. Cellular infiltrations and haemosiderin deposition were also found in most of the organs, especially in the spleen whose germinal centres were very much depleted. Morphological studies on H. longistipes from naturally and experimentally infected camels as well as from experimentally infected goats revealed a noticeable retardation in size and measurements of adult worms collected from infected goats as compared with those collected from camels, while measurements of larvae showed no differences. Vulvar region of female H. longistipes from infected camels were smooth in shape (unflapped). The prepatent period was much shorter (6 - 9 days) in infected camels when faecal culture technique was used (11 - 14 days) then when assessed by detecting eggs using sodium chloride floatation technique. Thus, faecal culture was a better method for detection of early infections.