An epidemiological study of gammaglobulin levels in newborn calves

The effect of various factors on serum gammaglobulin concentration in newborn dairy calves was studied in 181 calves on six commercial farms. The refractometer test for monitoring colostrum management was found to be a reliable, rapid and practical method up to 6 days after birth. The three factors, time of first colostrum feeding, quantity of first colostrum intake and gammaglobulin concentration in first colostrum, explained 19.9% of the variation in serum gammaglobulin concentration. Time of milking, time of first colostrum intake and gammaglobulin concentration in first colostrum explained 21.0% of the variation in serum gammaglobulin concentration. Calves from first lactation cows showed lower serum gammaglobulin concentration than calves of older cows.     

食品生产用动物及其健康关乎人类健康

正益生元的概念相对较新,不易消化的食物成分(如不能消化的低聚糖)可被一种或多种对肠道生理具有益作用的细菌选择性发酵,一些益生元可选择性地刺激肠道中内源乳酸菌和双歧杆菌的生长,增加益生菌数量,从而改善宿主健康。如果特定有益菌不存在,益生元就没有用处。同样,如果环境不利,活菌也不会产生效力。最近提出了共生概念,即同时含有益生元和益生菌属性的食物才是有益健康的功能食品。1益生菌和益生元能够改善动物健康、生产性     

Comparative studies on three isolates of Breda virus of calves

Three isolates of Breda virus of calves were compared morphologically and antigenically. The isolates demonstrated similar morphology and shared common antigens, as determined by enzyme-linked immunosorbent assay and immunoelectron microscopy. On the basis of results of the hemagglutination-inhibition test, enzyme-linked immunosorbent assay, and immunoelectron microscopy, the 3 isolates were further subdivided into 2 serotypes: serotype 1 (Breda virus 1) represented by the Iowa isolate 1; and serotype 2 (Breda virus 2), by the Ohio isolate and the Iowa isolate 2. The 3 isolates caused diarrhea in gnotobiotic calves.     

Anatomical studies into the ruminal mucosa of pygmy goats in relation to their age

The ruminal mucosa of 15 pygmy goats of different age (Z1 approximately 4-5 months, Z2 approximately 1 year, Z3 approximately 1.5-5 years) were studied gross-anatomically concerning their colour, clumping of papillae, fodder precipitations on the papillae, areas poor in papillae or devoid of them and the development of papillae. The density of papillae/cm2 in the 3 groups investigated was 79.4; 67.3; 58.0; the mean length of the papillae (mm) 1.75; 1.86; 2.96; the mean breadth of the papillae (mm) 1.3; 1.2; 2.0; the area of the ruminal mucosa (cm2) 799; 943; 1 195; the area of the ruminal pillars (cm2) 38; 41; 69; the number of the papillae/rumen 59,940; 58,022; 64,782; the total absorptive area (cm2) 3,802; 3,854; 11,268; the surface magnifying factor 4.0; 3.4; 8.4.     

Histological studies into the ruminal mucosa of pygmy goats in relation to their age

Ruminal mucosae of 15 pygmy goats of different age (Z1 approximately 4-5 months, Z2 approximately 1 year, Z3 approximately 1.5-5 years) and sex were investigated histologically. The thickness of the Stratum corneum of the 3 experimental groups was in the Atrium ruminis 23.0, 23.0 and 29.1 microns, in the Recessus ruminis ventralis 22.8, 28.0 and 30.0 microns, that of the Stratum germinativum and Stratum granulosum in the Atrium ruminis 74.8, 78.4 and 82.3 microns and in the Recessus ruminis ventralis 87.4, 84.7 and 87.7 microns, that of the Corpus papillare in the Atrium ruminis 75.3, 75.2 and 74.4 and in the Recessus ruminis ventralis 85.0, 78.9 and 71.6 microns. The cell nuclear volumes of the basal and parabasal cells of papillae originating from the Atrium ruminis (a) and the Recessus ruminis ventralis (b) in the individual experimental groups were in case of a 103.2; 100.2 and 117.3 microns3 resp. in case of b 93.4; 96.4 and 119.7 microns3.     

The present epizootological situation in intensively bred cattle in relation to the morbidity and mortality of calves during their rearing

The rise and mass incidence of intestinal and respiratory infections in calves kept in large herds depend on a joint influence of infective agents and numerous endogenous and exogenous factors, mostly with non-specific action. Therefore, purely medical approach fails to provide efficient prevention. Detailed epizootological analysis is needed for taking actual measures; the analysis should concern potential respiratory and intestinal pathogens and should also cover the persistent infections such as IBR, BVD-MD and others. The immunological profile of herd, very unfavorable with the high culling rate, will improve as a result of the introduction of a purpose-oriented vaccination programme, higher level of colostral nutrition, and separate rearing of calves, isolated from the dams, in calf houses managed by the all-in-all-out system.     

Further studies on the response to transplanted adult Ostertagia ostertagi in calves

Calves infected by surgical transplantation of adult Ostertagia ostertagi had raised levels of plasma pepsinogen and those in which the largest number of worms established also had elevated plasma gastrin concentrations. Despite the elevated plasma pepsinogen values, the abomasal pH of the animals did not change significantly, and there was no significant difference in the percentage establishment of adult parasites in calves previously infected with O ostertagi third stage larvae and those which had been maintained parasite-naive before transplant.     

The effect of energy-rich feed supplements for cows on the health of their calves]

Experiments were carried out with 24 pregnant cows and their calves. The cows were divided in 2 equal groups. One of these received a supplement of animal fat additional to the feed from 4 weeks a. p. to 6 weeks p. p. Apart from clinical examinations following laboratory investigations in the blood were performed: hematological parameters, cholesterol, lipids, free fatty acids, ketone bodies, protein, glucose, bilirubin, transaminases, alkaline phosphatase, Ca, Mg, P, K, Na, Cl. The addition of fat to the feed of cows influenced the energy metabolism of the cows, the body weight of the newborn ones and some hematological parameters (incl. protein) of the calves positively.     

ELISA to determine anti-K99 pilus antibody in the sera of normal and diarrhoeic calves

An ELISA to detect circulating antibodies against K99 pili, a major attachment factor to intestinal epithelial cells of Escherichia coli in calves, was performed. Two methods of K99 pili purification were attempted. Best results in terms of purity of the K99 antigen were achieved following the method described by Karkhanis and Bhogal (1986). This procedure included a heat shock at 65°C during 25 min to release the pili and ultracentrifugation steps to purify the antigen. SDS-PAGE showed an 18 KDa major band, identified as the K99 pilus antigen after immunoblotting against reference antisera. The purified K99 antigen was then adsorbed to the ELISA microplates. High optical density was obtained in the ELISA using a pool of sera from immunized cows. No differences in antibody levels (P ≥ 0.05) could be detected between clinically healthy calves and those showing diarrhoea.