Immune response in anaemic calves

Trace element deficiencies in cattle

Deficiency of cobalt, copper, iron, iodine, manganese, selenium, or zinc can cause a reduction in production. Reduced production occurs most commonly when a deficiency corresponds to the phases of growth, reproduction, or lactation. Because of environmental, nutrient, disease, genetic, and drug interactions, deficiencies of single or multiple elements can occur even when the levels recommended by the National Research Council for these nutrients are being fed. Additionally, random supplementation of trace elements above National Research Council recommendations is not justified because of the negative interaction among nutrients and potential toxicosis. Evaluation of trace element status can be difficult because many disease states will alter blood analytes used to evaluate nutrient adequacy. Proper dietary and animal evaluation, as well as response to supplementation, are necessary before diagnosing a trace element deficiency.

Comparative evaluation of specific vaccines and immuno-modulators in disease control of beef cattle

Two field trials were undertaken to evaluate specific vaccines and Biological Response Modifiers (B.R.M.) with regard to disease control of beef cattle. Clinical data and laboratory results strongly suggested a genetically determined resistance to transportation stress of some cattle breeds, with possible important consequences on the occurrence of multi-factor diseases. Plenty of calves showed detectable levels of serum interferon and a remarkable activation of at least some lymphocyte populations in the first days after arrival. In general, B.R.M.-treated cattle could better react against environmental pathogens, as evidenced by both clinical and laboratory findings. Several data emerged that even the efficacy of specific vaccines could be largely accounted for by a positive modulation of non-specific immunity; this latter feature can be mainly referred to adjuvants and/or some bacterial antigens.

Characterization of some parameters of non-specific immunity in dairy cattle (I)

The concentrations of serum protein and immunoglobulin, complement, lysozyme, serum bactericidal activity and blast transformation of peripheral blood lymphocytes were assessed in dairy cattle in different herds and age groups. The study aimed at defining fundamental aspects of non-specific defence under the field conditions, related to age/season/management influences. The observed differences in the expression of these parameters are discussed, with regard to their role in the immune defence of calves and their relation to colostrum uptake. The possible use of these parameters in the control of animal welfare is stressed and the possibility is put forward of predicting possible unfavourable interactions with environmental pathogens.