Indigestion in Young Calves VI: Studies of Diarrheic Calves Fed Milk Replacers Made of Normal and Heat-Treated Skim Milk and whey Powder

Diarrhea occurred in 12 pre-ruminant calves after the introduction of milk replacers. Six of the calves were fed a replacer made of normally treated skim milk and whey powder, while the other 6 got a replacer made of heat-treated powders, although otherwise similar to that of the first group. Abomasal curd formation was deficient in calves fed for 9 or 17 days on the heat-treated replacer (4 of 6 calves). Otherwise, no clear differences between the calves given normally treated and heat-treated replacer occurred, as regards diarrhea, bacteriological, virological, and pathomorphological findings in the intestinal tract. Rotavirus and chlamydial infections were indicated and considered as the major cause of the diarrheic condition, although bacteria, including coliforms and Pseudomonas aeruginosa, may have contributed. The milk replacers may have been involved was provoking factors.Key words: heat-treatment, skim milk, whey, diarrhea, curd formation, intestinal microflora, rotavirus, chlamydia, calves     

Prevalence of Treponema hyodysenteriae in healthy pigs.

The prevalence of Treponema hyodysenteriae in faecal samples from healthy pigs of various ages in different farrowing units was investigated.Samples from herds designated as Category I were processed within 2 hrs. of sampling. Samples from herds designated as Category II were transported 2 to 3 days before cultivation procedures started. T. hyodysenteriae was demonstrated in 53.7 % to 93 % of the samples collected from Category I herds. No marked difference in the frequency of positive samples from the various age groups of pigs was found. In Category II herds, the organism was demonstrated in 10 % of the samples.The degree of beta-haemolysis shown by isolated strains was grouped into 3 groups: weak, moderate and strong. Strongly betahaemolytic strains, supposedly enteropathogenic, were demonstrated in all Category I herds. Such strains were found in 4.6 % to 25 % of the positive samples in these herds. In Category II herds, 2 out of 17 positive samples harboured strongly beta-haemolytic strains of T. hyodysenteriae.The amount of growth of T. hyodysenteriae on primary plates inoculated with sample material originating from the 2 categories of herds was mostly moderate or abundant. Strongly beta-haemolytic isolates originating from Category I herds produced abundant growth on primary plates in approx. 60 % of samples harbouring such strains. In samples from Category I herds with strains producing weak or moderate beta-haemolysis sparse and moderate amount of growth of the organism was predominant.     

Serological, enterotoxin-producing and biochemical properties of Escherichia coli isolated from piglets with neonatal diarrhea in Norway

Altogether 235 strains of Escherichia coli isolated from jejunal content of piglets with neonatal diarrhea were examined for serological, enterotoxin-producing and certain biochemical properties. Of 198 strains examined, 84 (42 %) belonged to O-group 149, while 14 (7 %) strains belonged to each of the O-group s 8 and 64. Seventy strains (30%) could not be grouped with the sera used. The remaining strains were distributed among the following O-groups with only a few strains in each group: 2,6,9,32,45,98 and 141. Eighty out of 84 E. coli strains of O-group 149 possessed the K88 antigen and produced heat labile enterotoxin (LT). Besides, LT production was demonstrated in 3 out of 14 strains of E. coli 08. K88 antigen was demonstrated in only 1 strain not belonging to O-group 149. Among strains of E. coli 064 12 out of 14 were K99 positive. This antigen was not demonstrated in E. coli strains of other O-groups. A close relationship was demonstrated between strains of E. coli 0149 possessing the K88 antigen and the ability to ferment both raffinose and adonitol. This ability was only detected in 2 other strains of E. coli not belonging to O-group 149.     

Design and operations of the Kaldnes moving bed biofilm reactors

The moving bed biofilm reactor (MBBR) was developed in Norway in the late 1980s and early 1990s. It is covered by several patents and has been a huge success world-wide for treatment of municipal and industrial wastewaters. In addition, MBBRs have been successfully used for biological treatment of drinking water as well as for water treatment in fish farms. The MBBRs use plastic biofilm carriers of a unique design, to maximize the active biofilm surface area in the reactors. Reactors have insignificant headloss, no need for periodic backwashing and no susceptibility for clogging. This paper describes the fundamentals of the MBBR. It has a major emphasis on nitrification with the type of biofilm carrier used in fish farms, but briefly touches upon removal of organic matter and denitrification. Major factors influencing the nitrification rates in MBBRs are discussed in detail. Results from small-scale MBBR tests, as well as from commercially operated MBBRs at full scale fish farms are presented. The data are from both freshwater and marine applications.     

Toxicity studies with the blue-green alga Oscillatoria agardhii from two eutrophic Norwegian lakes

Extracts of the blue-green alga Oscillatoria agardhii were tested for acute toxicity on laboratory mice and rats. Material originating from lake Gjersjøen proved to be toxic to the animals, samples from the nearby lake Årungen did not. Clinical symptoms culminated in the development of a fatal shock due to decrease in circulating blood volume. Pathological examination revealed heavy pooling of blood in the liver and severe damage to the organ. Blood analyses also indicated liver damage. Effects were the same with extracts from a laboratory clone culture as from a natural water bloom, but the toxin content was higher in the bloom material. Toxicity was not affected by heat, acid or alkali treatment.     

Single Cell Protein in the Diets of Pigs and Chickens: Effects on the Activity of Dnase in Intestinal Contents

Pigs and chickens were fed diets containing increased concentrations of the single cell protein (SCP), Pruteen, in order to investigate the effects of a diet containing high levels of nucleic acids on the activity of DNase in intestinal contents. Increased levels of SCP in the diet generally resulted in increased DNase activity in intestinal contents.Significant differences at P≦0.05, were found between the control groups and most of the experimental groups in both species.With the exception of the 2 groups given the highest levels of SCP in the chicken experiment, the DNases in the large intestines were not inhibited by antisera produced against DNase in pancreatic juice.     

Deoxyribonuclease inhibitory activity in pig intestinal contents

The inhibitory effect of pig intestinal contents on some microbial DNases and bovine pancreas DNase was examined employing an agar diffusion test. The molecular weight of 1 inhibitor as well as the electrophoretic patterns of the inhibitors were determined.DNases from Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Clostridium perfringens and bovine pancreas were inhibited by intestinal contents. DNases from Clostridium septicum, Serratia marcescens, Proteus mirabilis, Aeromonas hydropnila and Pseudomonas aeruginosa were not inhibited. The concentrations of the inhibitory substances were considerably higher in contents from the small intestine than from the large intestine.Using electrophoretic procedures on intestinal contents, 3 different fractions showing DNase inhibition were demonstrated. The molecular weight of one of the inhibitors was estimated to be about 30000.     

Infection with Actinobacillus Suis in Pigs

Actinobacillosis in pigs seems to be relatively rare and when it does occur, it usually manifests itself as acute septicaemia during the first weeks of life (Zimmermann 1965). Polyarthritis, pneumonia and heart lesions as well as petechial haemorrhages in skin, viscera and kidneys are also frequently found (MacDonald et al. 1976, Jones & Simmons 1971). Both Actinobacillus suis and Actinobacillus equuli have been isolated from such cases (Pedersen 1977).