Cytokine mRNA expression in bronchoalveolar lavage cells during Dictyocaulus viviparus infection in calves.

The purpose of this study was to monitor local cytokine responses to Dictyocaulus viviparus in calves during primary infection and re-infection. Bronchoalveolar lavage fluid (BALF) was collected weekly from experimentally infected calves and interleukin-2 (IL-2), IL-4, IL-5, IL-10 and IFN-γ mRNA expression was quantified in BALF cells. The major finding was a prominent transient increase in IL-4 mRNA expression, compared with that of uninfected calves, observed in BALF cells collected 2-3 weeks post-primary D. viviparus infection. At 2 weeks post-infection, macroscopic worms were also first observed in BALF. Calves re-infected after 10 weeks were partially immune which was evident at slaughter 5 weeks post-infection as a lower worm burden than in previously naïve calves infected at the same time. IL-4 mRNA expression in BALF cells 2 weeks post-re-infection was increased compared with that of uninfected animals but not as high as that of primarily infected calves. BALF cell expression of the other cytokines tested for was not as clearly effected by the D. viviparus infection. It seems likely that the strong IL-4 response observed during primary infection reflects an innate response to the worms that may initiate an ensuing Th2 response, which confers protective immunity.

[Determination of the status of lipid peroxidation and antioxidants in cattle infected with Dictyocaulus viviparus]. / Dictyocaulus viviparus ile Enfekte Sigirlarda Lipit Peroksidasyon ve Antioksidan Durumunun Saptanmasi.

Endoparasites cause significant economic losses and health problems in domestic animals. In this study, lipid peroxidation and the antioxidant status were investigated in the lung tissue taken from twenty cattle infected with Dictyocaulus viviparus and ten healthy cattle. Malondialdehyde superoxide dismutase, catalase, glutathione, vitamin C and beta-carotene were measured. In comparison to the control group, the concentration of MDA was high (p < 0.001), but the activities of Cu-Zn-SOD and CAT, and the concentration of GSH, vitamin C and beta-carotene were low (Cu-Zn-SOD, CAT, GSH, vitamin C, p < 0.001 and beta-carotene p < 0.05) in the parasite infected group. These results suggested that endoparasitic infection is among the major causes of oxidative stress. Lipid peroxidation was observed and the activities and concentrations of antioxidants systems were decreased in the lungs of cattle infected with Dictyocaulus viviparus.

[The interrelation of the phospholipid composition of the lungs in sheep and of the nematode Dictyocaulus filaria]. / Vzaimosviaz' fosfolipidnogo sostava legkikh ovtsy i nematody Dictyocaulus filaria.

The effect of nematodes Dictyocaulus (D) filaria on phospholipid (PL) composition in the homogenate of sheep lungs has been demonstrated. The comparative analysis has shown no differences in the content and composition of PL in the lungs of healthy sheep and in nematodes. Infection of sheep by helminths was found to result in changes in the PL composition of sheep lungs. Thus, it is possible to conclude that D. filaria affecting structural and functional systems of the host causes changes in its PL content.

Nutritional and dietary interrelationships with diseases of grazing beef cattle.

This article describes current methods of controlling acute bovine pulmonary emphysema (ABPEE) and edema, lungworm and gastrointestinal nematodes, and bloat in grazing beef cattle. Success in handling outbreaks of these conditions and in their prevention depends on an understanding of their epidemiology and pathogenesis. Supplementation with ionophore antibiotics is effective in prevention of ABPEE and bloat and may also prevent other diseases of cattle that graze lush pastures.

The effects of Dictyocaulus viviparus infection on energy metabolism of calves.

To determine the effects of lungworm infection on energy metabolism and rate of weight gain, five 3-mo-old male Friesian calves were infected orally twice each week with 640, third-stage larvae of Dictyocaulus viviparus (D.v.) over an 8-wk period. Infected calves were matched with uninfected controls on the basis of similar rates of feed consumption and weight gain during the acclimation period before infection. Infected calves were fed 2 kg of concentrates daily (88% DM), about 8.5 Mcal/d. Controls each received approximately 250 g less, about 7.5 Mcal/d. Similar amounts of hay (5.6 to 5.8 Mcal/d) were provided to all calves. Clinical, serum chemical, hematological and parasitological criteria, weight gain and utilization of energy were monitored on a weekly basis. Serum chemical and hematological analyses and clinical examinations of infected animals revealed signs typical of lungworm infection. Fecal and sputum sample examinations for infected calves were positive for D.v. larvae and ova, respectively. Control animals gained approximately 80 g.animal-1.d-1 more than infected calves. Lungworm infection had no significant effect on digestibility of energy or protein. Metabolizability of energy ingested was somewhat higher in the infected calves due to a higher dietary concentrate to roughage ratio. Utilization of metabolizable energy and protein tended to be less efficient for infected animals. Results showed that D.v.-infected calves need more feed for gain than do uninfected animals. This extra requirement is due to an increased maintenance requirement and probably to a reduced protein retention from digested protein.

Effect of infection with lungworms (Dictyocaulus viviparus) on energy and nitrogen metabolism in growing calves.

1. Ten Friesian male calves of about 100 kg and 3 months old were reared similarly and were worm-free. From 13 weeks of age five calves received a dose of 640 infective larvae (L3) of lungworms (Dictyocaulus viviparus) twice weekly for 8 weeks to simulate continuous infection. Animals not infected were fed to the same level as the infected animals (about 1.2-1.3 kg concentrates and 1.4-1.5 kg good-quality hay/d). 2. Heat production was measured twice weekly during 48 h (days 2 and 3, and days 5 and 6) in each group of experimental animals. 3. Infection caused considerable damage to the lungs, increased respiration frequency and clearly produced antibody titres against D. viviparus. 4. Animals infected with lungworms had on average a lower rate of weight gain, reduced by 70 g/d per animal. Digestibility was not affected. Nitrogen retention was much lower in infected animals (12.0 v. 14.6 g/d per animal in controls). 5. Metabolizability of energy was slightly reduced in infected animals. Heat production as found in infected animals may be associated with an increased maintenance energy requirement of 30 kJ/kg live weight 0.75 per d or reduced partial efficiency of feed conversion above maintenance in animals infected with lungworms (58.5 v. 64.1% in the control animals). 6. It was concluded that the depression in rate of gain was related to reduced intake of feed and to decreased N retention.