Showing papers by "Animal Research Institute published in 1979"

Relationship Between Egg Shell Quality and Shell Breakage and Factors that Affect Shell Breakage in the Field–A Review

Abstract: About 6 to 8% of the eggs annually produced are broken or cracked between the hen and the consumer's carton. The majority of this breakage is due to interrelationships between egg shell quality and...

Lipid composition of oats (Avena sativa L.)

Abstract: Compositions of lipids extracted from a sample of Hinoat oat by seven solvent systems and that extracted with chloroform/methanol (2:1 v/v) from six selected cultivars representing high and low lipid contents are reported. Lipid components (steryl esters, triglycerides, partial glycerides, free fatty acids, glycolipids and phospholipids) were separated by silicic acid column chromatography and thin layer chromatography and quantitated by GLC analysis of fatty acids and phosphorus determinations. Twelve oat cultivars were examined for the fatty acid composition of lipid extracted with n-hexane. Lipids extracted from Hinoat by different solvent systems ranged from 5.6 to 8.8%. Quantitative distribution of lipid components extracted with chloroform/methanol from six cultivars containing 4.6 to 11.6% lipid showed a significant correlation (γ=0.99) between the total lipid and the neutral lipid content. Phospholipid content was similar in all cultivars, but glycolipids showed a two-fold increase in high lipid oats. Triglycerides contained less palmitic and more oleic acid than the glycolipids or phospholipids. Nine glycolipids and 11 phospholipids have been identified, and the polar lipid composition of Hinoat oat is presented.

Uv and visible absorption spectroscopic investigations in relation to macromolecular characteristics of humic substances

Abstract: Summary Humic substances were investigated by both UV and visible absorption spectroscopic methods with special emphasis on their macromolecular characteristics. The spectral ranges examined were 200–350 nm and 350–700 nm. Conclusions were drawn on the basis of absorption intensities in optical density (O.D.) vs. wavelength (λ) curves, slopes of log O.D. vs. log λ plots, nature of shoulders in the 250–270 nm region, and E4/E6 ratios. As macromolecular characteristics are expected to be dependent on the medium, studies were carried out at different pH values as well as at different neutral salt concentrations, the two major parameters influencing the soil environment. It was noted that with increasing neutral electrolyte concentrations, the particle size decreased, probably due to the coiling of the macromolecule. On increasing the pH from 6.5 to 9.5, the particle size increased slightly, possibly because of partial association through homolytic bonding. At pH 3.5 (with FA only), the degree of association was greater than that at pH 9.5. However, here association occurred by a different mechanism, that of intermolecular hydrogen bonding. At pH 2.0 (with FA only), association was markedly pronounced because of the very dominant role played by intermolecular hydrogen bonding.

Some aspects of the epidemiology and control of bovine babesiosis in Australia.

Abstract: A short account of the epidemiology and control of babesiosis in Australia is presented. Epidemiological topics discussed include differences in the transmission of Babesia bovis and B. bigemina by the cattle tick, Boophilus microplus and the relative prevalence, disease incidence and pathogenicity of B. bovis and B. bigemina. Circumstances under which babesiosis occurs in Australia are described. In the Section on control, only vaccination is discussed. Changes in the preparation of babesial vaccines, particularly those resulting in a highly infective vaccine containing relatively avirulent B. bovis are described. Fluctuations in demand, such as the increase from about 100,000 to over 1,000,000 doses in 4 years in the mid-1960s are shown. An unexpected increase in the use of A. centrale in 1973 is discussed, and the supply of B. bigemina for cattle exported from Australia reported.

Bacterial penetration in floor and nest box eggs from meat and layer birds

Abstract: A method similar to that used by Board and Board (1967) was used to determine the numbers of eggs penetrated by bacteria on 3 poultry farms in south-east Queensland. Significant differences in the percentages of penetrated eggs between the eggs of layer birds (9.7%) and the eggs of meat birds (16.1%) and between nest eggs (10.5%) and floor eggs (15.3%) were detected. The distribution of the numbers of penetration points was similar for nest and floor eggs for both types of bird and was independent of shell surface area or thickness.

Oat Starch: Some Recent Developments

Abstract: Starches from Canadian oat varieties have been examined. Iodine affinity, solubility and λmzx of the iodine complex are lower than those found for other cereal starches. Swelling power, limiting viscosity number and hot paste cooling curves are all higher than for other cereal starches. Gel chromatography reveals a fraction of molecular weight between amylose and amylopectin and which is present in greater amount than that found in wheat starch. The β-amylase digestion limit is lower than that found for wheat and corn and may suggest a more branched structure for oat starches.

Growth, Lipid Metabolism and Pathology of Two Strains of Rats Fed High Fat Diets

Abstract: Studies were carried out on Sprague-Dawley (SD) and Chester Beatty (CB) rats to determine whether the difference in incidence of myocardial lesions can be related to dietary factors and parameters known to be affected in SD rats fed rapeseed oils. The two strains of young, male rats were fed diets which contained 20% by weight of either corn, LEAR (low erucic acid) or HEAR (high erucic acid rapeseed) oils for a period of up to 16 weeks. A significantly lower incidence of focal myocardial necrosis was observed in CB rats than in SD rats. The incidence of this heart lesion in CB rats was similar between all diets; in SD rats a higher incidence was observed in the groups fed rapeseed oils. In both strains the growth rates of rats fed LEAR and corn oils were similar; growth rates with HEAR oil diets were much lower than the other oils. Severe myocardial lipidosis was only evident in rats fed HEAR oil, but no strain differences were observed. The pattern and extent of lipidosis, including cardiac and hepatic lipid levels and fatty acid compositions, were similar in both strains at the time periods studied. Cardiac triglycerides and free fatty acids increased in rats fed HEAR oil, but no strain differences were evident. Strain differences were found in the levels of a few cardiac phospholipids of rats fed HEAR oil, however, the relative fatty acid compositions of each phospholipid were remarkably similar. Microscopic examination of the livers showed no evidence that feeding rapeseed oil caused any specific effect which could be related to differences in heart lesion response. There was no evidence to indicate that differences in heart lesion response between the two rat strains could be related to cardiac triglycerides, free fatty acids or phospholipids.

Studies on genetic resistance of chickens to Marek's disease--a review.

Abstract: Marek's disease (MD) in chickens is caused by a herpesvirus and is characterized by development of lymphoid tumors. Although vaccines have dramatically reduced losses from MD, genetic resistance, as well as vaccine-induced immunity are essential to minimize the incidence of this disease. Genetic variation in resistance of chickens to MD has been amply demonstrated. Parallel comparisons of vaccinated and non-vaccinated strains showed that MD incidence was decreased by vaccination but this had not altered the ranking of strains on MD incidence. Significant genetic variation has also been found in resistance of chickens to the MD tumor transplant JMV but data on the correlation of this resistance with resistance to MD were inconsistent and the use of JMV for testing genetic resistance to MD is of questionable value. Estimates of heritability of MD resistance were high (61%) suggesting good potential for genetic improvement. Resistance to MD tends to be genetically associated with lower body weight, lower egg weight and higher egg production. Thus there is a danger of reducing MD resistance in populations under selection for rapid growth and/or high egg weight, while populations selected for high egg production would be expected to maintain or improve their MD resistance. Conclusive evidence is available that the major histocompatibility locus plays a role in MD resistance and this has potential value in commercial poultry breeding.

Crofton weed (Eupatorium adenophorum) toxicity in horses.

Abstract: The clinical signs and pathology of 6 field cases of a respiratory disease of horses which occurs in the coastal hinterland of south-eastern Queensland are described. The condition has occurred for many years and has been thought to have been associated with ingestion of Crofton weed (Eupatorium adenophorum). Coughing, rapid heaving respiration, decreased exercise tolerance and loss of condition were seen in affected horses. In longstanding cases fibrosis, alveolar lining cell proliferation, oedema, neutrophil infiltration and abscessation were seen. In some cases vascular thrombosis and infarction occur in the lungs. Similar signs and lesions occurred in one horse fed E. adenophorum for 8 months and early lesions in another fed the flowering stage of the plant for about 6 weeks. Lesions also developed in 2 rabbits experimentally fed the plant, but not in sheep or rats.

The toxicity of cassia occidentals for cattle

Abstract: SUMMARY An investigation into the toxicity of Cassia occidentalis seeds was undertaken to confirm the toxicity of this species and to more fully characterise the pathology of the condition. Hammermilled seeds were given to calves by stomach tube. Five calves died and 3 were killed in an advanced stage of intoxication 6 to 9 days after the last dose. Clinical signs observed included diarrhoea, anorexia, reluctance to move, stumbling swaying gait, recumbency, tachycardia and dyspnoea in the terminal stages. Red-brown urine was present in most calves from the fourth day. Terminally, there was a neutrophilia and greatly elevated serum GOT and CPK levels. Autopsy revealed pale skeletal muscles of the upper pelvic limb and a characteristic red stippling giving a banded appearance in some affected muscles. Marked pulmonary oedema was present and the myocardium had a streaky mottled brown appearance. Light and electron microscopic examination revealed severe myodegeneration of skeletal muscles, myocardiopathy and focal hepatic necrosis.

Epidemiology and control of anaplasmosis in Australia.

Abstract: Anaplasmosis occurs in those areas of northern and eastern Australia infested by the cattle tick Boophilus microplus but it has been studied intensively only in Queensland. Anaplasmosis is predominantly a disease of autumn and winter and of cattle greater than 1 year of age. The complement fixation test has been used in serological surveys of the tick-infested areas of the state. Both clinical and subclinical infections occur only in tick-infested areas and they are both more frequent in Bos taurus than in Bos indicus cattle probably due to the greater susceptibility of the former to ticks. Prevalence of infection is significantly greater in cattle exposed to heavy tick infestations than it is in cattle exposed to light tick infestations. B. microplus is considered to be the main vector with transmission being effected by transtadial and intrastadial but not transovarial means. Transtadial transmission by Rhipicephalus sanguineus has been demonstrated but attempts to demonstrate transmission by Haemaphysalis longicornis were unsuccessful. Vaccination with Anaplasma centrale is employed either as a routine preventative measure in young cattle or in the face of an outbreak. Attempts to attenuate a strain of A. marginale by adapting it to sheep were unsuccessful. Oxytetracycline and imidocarb have been used successfully to control the clinical disease.

Infection studies on a reticuloendotheliosis virus contaminant of a commercial Marek's disease vaccine.

Abstract: SUMMARY: Reticuloendotheliosis virus (REV) was isolated in cell cultures from commercial Marek's disease (herpesvirus of turkeys) vaccine and re-isolated from the organs of vaccinated chickens. Runting and feathering abnormalities were produced when 1-day-old specific pathogen free chickens were Inoculated with REV. Histopathological lesions in infected chickens were hypoplasia of the thymus, bursa and spleen, and inflammation of the proventriculus, kidneys and liver. Serological responses to REV were detected by the indirect immunofluorescence test in chickens directly inoculated with the contaminated vaccine, and spread of REV infection to in-contact chickens was demonstrated by histopathological and serological investigations.

Fatty Acid Composition of Margarines in Canada

Abstract: Ninety five brands of Canadian margarines were analyzed for fatty acids, with particular reference to cis-cis -methylene interrupted (CCMI) and trans unsaturated fatty acids by GLC and enzymatic methods. The samples included 52 soft, 39 hard and 3 semisolid margarines and one spread containing butter. Forty five out of 95 samples analyzed contained less than 10% CCMI and 32 contained more than 30% CCMI. Eighty two of the 95 samples contained trans -unsaturated acids above 10% of which 47 had levels between 25 and 40%. The major portion of trans -acids was composed of the monoene, elaidic acid; trans -dienes ranged from 0.3 to 5% in 13 samples of which 3 samples showed appreciable quantities of t,t -18:2 and one of c,t -18:2. A significant correlation (γ = 0.97) was obtained between CCMI determined by GLC and enzymatic methods.