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Summary Homozygous transferrins of adult cattle are made up of two strong pairs and one weak pair of protein bands on starch gel electrophoresis. Foetal transferrins have only the slower band of each pair with the fastest band of the three being much stronger than in the adult type. Before term the second band of each pair begins to develop and at the same time the fastest pair becomes weaker – attaining the adult type by term or soon after. The ai protein, which is present in early foetal life and almost disappears by 250 days of embryonic development, shows individual variation. Its relationship to fetuin is discussed.

Summary Amylase activity has been estimated in the sera of 213 cattle by an amyloclastic method with potato amylose as the substrate with the addition of CaCl2. The method has been developed from that of Street and Close to overcome the problems of the high colour of bovine serum which would otherwise interfere with the assay. A relationship has been found between the serum amylase genotype detected on starch-gel and the total enzyme activity. The enzymes AmI-B and AmII-B in homozygous combinations have been found to have the highest activities. Age of animal has no significant effect on the total enzyme activity. Activity has been investigated in sera from three separate cattle populations and it has been found to be a highly heritable character. Heritability estimates of 49 % and 39 % by sib analysis and 75 % by the twin method have been obtained.

Summary Two genetically controlled polymorphic systems of amylase enzymes are described in sera from Friesian, Jersey, Guernsey, Hereford, Ayrshire and Charolais cattle. One of these Ami has been described previously and is controlled by two codominant alleles in British cattle, AmIB and AmIC. Evidence presented here suggests that it could be a gamma.amylase. The other enzyme which is described here for the first time has many of the properties of an alpha amylase. It is also polymorphic and controlled by two codominant alleles AmIIA and AmIIB. AmIIA is only present in low frequency. The inheritance of both enzyme systems has been studied in 419 families.

BoLA specificities wl w2 w5 w8 w9 wlO and wll have been re-examined by absorption. All of the clusters except w9 showed evidence of sub-group specificities, but only in some cases (wl, w5, v8 and wll) is it suggested that the definition should be revised. The results show a very high degree of reproducibility between sera from different laboratories with clusters of narrow and wide sera for most specificities. These behave in all the cases reported here as linear sub groups or inclusion groups.

1. 1. Individual components of two of the variants of sheep (Ovis aries) transferrin were isolated. 2. 2. There was one main component with three residues of sialic acid per mole of protein and a faster component with four residues. 3. 3. There was no evidence for pairs of bands with the same number of sialic acid residues, as seen in cattle (Bos taurus). 4. 4. Sedimentation equilibrium ultracentrifugation showed that the bands of a single variant have a molecular weight of 77,000. 5. 5. Finger print studies showed at least 4 peptide differences between the two genetic variants. The amino acid composition was similar to that of cattle transferrin. 6. 6. The results provide evidence that sheep transferrin is a single polypeptide chain.

Homozygous cattle transferrin has been fractionated into six main peaks by DEAE-Sephadex chromatography. These correspond to the six transferrin components seen in starch gel electrophoresis of normal serum. In addition, six more minor components were isolated from DEAE-Sephadex, making 12 in all, and these could be divided into six pairs. Treatment of whole transferrin with neuraminidase yielded only two bands. Treatment of the individual fractionated bands showed that the slower band of each pair had the same mobility as the slow band from treated whole transferrin, while the faster band from each pair corresponded with the fast band of treated whole transferrin. These observations, and the results of sialic acid assays, showed that the difference between the pairs of bands was caused by differing numbers of sialic acid residues (0–5) per molecule of protein, but that sialic acid was not responsible for the difference between the bands within a pair. The mode of genetic control is discussed and probably involves three loci. Other physicochemical properties of cattle transferrins, namely, molecular weight, effect of iron addition, and behavior in isoelectric focusing, were also studied.

A method of micro-titration for cytolytic antibodies is described. Standard drops of diluent are placed on a subdivided siliconed slide and dilutions are made by rotating a wire loop holding 1 drop of serum in each drop sequentially. One drop of a mixture of cells and complement is then added. The slide is incubated in a moist chamber for 90 min at 37° C. after which a small cover-slip is placed on each drop and the amount of cell lysis, judged by phase-contrast microscopy, is graded.An analysis of variance of the method has been performed and the method has been found to be reliable, accurate and unbiased.It allows accurate estimates of cytolytic activity in sera using cell concentrations of 104to 105cells per ml. Eight ten-dilution titrations can be carried out with 1 ml. of such a suspension.

An experiment was conducted to examine the addition of zinc in nutritive rich feed contained lemuru oil to growth and birth weight of Bali cattle. The experiment design used was randomized complete block design. The animal were randomly assigned into four group of treatments, i. e addition of 0, 75, 150 and 225 mg ZnSO4 kg -1 on nutritive rich feed (NRF) containing lemuru oil. The basal diet consist dried grass while NRF consisted of palm sugar, leucaena and glirisidia leaf meal, rice bran fermentation, fish meal, lemuru oil and urea. The crude protein content of NRF was 23%, while total digestible nutrient (TDN) was 70%. Addition ZnSO4 in the diet did not increase significantly zinc status, prostaglandin E2 (PGE2) concentration and ME retention. However, level of ZnSO4 addition increase significantly (P

Seven cases of an abnormality in bovine transferrins are described. In this abnormality the two fastest strong protein bands apparently have the same mobility as the two slow bands. It has been seen in Tfa2, Tfd1, and Tfd2 transferrins. The characteristic which has only been found in the Hereford breed could be explained by a recessive epistatic gene affecting the sialic acid binding to the two faster strong protein bands of the four controlled by each Ifallele.

In this paper family studies are presented which support the hypothesis of polymorphism in the process controlling sialic acid binding to bovine transferrin which modifies its phenotype as seen in starch gel electrophoresis. It has been shown that this polymorphism is controlled by locus Tfs with two alleles Tfs A and Tfs a. Tfs a/a animals have the abnormal phenotype with the two faster bands of the four bands of a normal transferrin allele being virtually absent. Tfs A/a and Tfs A/A are phenotypically normal. Limited evidence is presented which suggests that the Tf and Tfs loci are not linked.

Summary 1. The inherited differential agglutinability of cattle erythrocytes is shown to be similarly expressed on ghosts and intact cells. 2. Removal of virtually all sialic acid by prolonged neuraminidase treatment does not alter the agglutinability status of ghosts prepared from either high or low agglutinable cells. Hence the differing sialic acid content of the two cell types is not responsible for the differential agglutinability. 3. The significance of these findings with respect to other well defined agglutination systems and current theories of membrane structure is discussed.

Summary This paper describes the effect of gel buffer pH on the resolution of bovine serum amylase (Amylase I) isozymes in starch gel and the consequences for the understanding of the genetics of this locus. The two main findings are: (1) the existence of a satellite isozyme E to isozyme C which at pH 7.3 has the same mobility as the B isozyme but which at pH 8.0 migrates slower than B, and (2) the finding of three alleles AmI A, AmI B and AmI C in British cattle populations previously reported as having only AmI B and AmI C.

Summary Red cell potassium concentrations were determined in 5 breeds of cattle. Most cattle had red cells with less than 50 mmol K/litre and although a few Hereford and Friesian cows had levels approaching 70 mmol K/litre, it was only in the Jersey breed that values above this were found. Attempts were made to correlate potassium levels with serological specificity using cattle S system and sheep M system blood typing reagents. Red cells negative for cattle factors S, H‘, and S were never positive for sheep L; cells positive for H’ were usually positive for M, and those positive for S were always positive for L. No obvious relationship was found between potassium levels and serological type, although some consistent trends were noted in Friesians and Herefords. Limited family data indicated that a major difference in potassium levels of red cells in cattle may be controlled by two codomi-nant alleles.

Ox red cell membranes have been extracted with butanol. The presence of F, V, J, L, R′, S′, and T′ has been detected in the protein fraction but all activity for other blood group antigens was lost. Protein has been used for isoimmunization in cattle and produced high titre antibodies specific for the injected antigen.

The single-banding components of bovine transferrin from animals homozygous for the four transferrin variants found in the U.K. were isolated. Sedimentation equilibrium ultracentrifugation and sodium dodecyl sulphate–polyacrylamide-gel electrophoresis showed that the bands of a single variant have molecular weights of 77500 and 73300 respectively. The different bands of a single variant and single bands of different variants show no evidence of size heterogeneity or of low-molecular-weight peptides being split off after reduction in 6m-guanidine hydrochloride. The two slower bands of a single variant, which both contain 2 molecules of sialic acid/molecule of protein, have the same molecular weight and amino acid composition, and give identical peptide ‘maps’, although differences in composition and peptide ‘maps’ occur between the different variants. The results support the concept that bovine transferrin is essentially a single polypeptide chain, but they do not explain differences in electrophoretic mobility between bands of the same variant which are not produced by differing sialic acid content.