Mineral resources, environmental issues, and land use

Contrary to predictions from the 1950s through the mid-1980s, persistent shortages of nonfuel minerals have not occurred, despite prodigious consumption, and world reserves have increased. Global availability of raw materials is relevant to policy decisions regarding mineral development and land use. Justification for environmental protection may exceed that for mining a specific ore body. Demand for environmental accountability is rising worldwide, and new technologies are enabling internalization of costs. Mineral-rich developing nations plagued by inefficient state-owned mining enterprises, high population growth rates, and environmental degradation could realize substantial benefit by reforming government policies to encourage foreign investment in resources and by appropriate allocation of mineral rents.     

Complement fixing and agglutinating antibody responses and leptospiruria in calves inoculated with Leptospira serotypes pomona,hardjo, copenhageni or ballum

Extract

Infection of cattle with various serotypes of Leptospira may result in a variety of clinical signs, including haemoglobinuria, abortions, stillbirths or atypical mastitis. In many instances, however, a mild infection occurs in which clinical signs are not observed. In these cases diagnosis is based on serological evidence.     

Leptospirosis in pigs: The effectiveness of streptomycin in stopping leptospiruria

A trial was conducted to assess the efficacy of a single intra-muscular injection of 25mg per kg of streptomycin in stopping leptospiruria in growing pigs exposed to a natural infection.

The investigation involved 54 pigs, 10–12 weeks old, that were free of serological evidence of infection with serotypes pomona or tarassovi at the start of the trial. The animals were kept in pens in a finishing house through which flowed effluent from other pens containing infected pigs. Urine samples were collected from each pig three times weekly until it was slaughtered for bacon at 20–24 weeks old.

Leptospiruria was first detected between 16 and 74 days after exposure. Twenty-one of 37 pigs which showed leptospiruria were injected with streptomycin. Leptospirae were detected in 11 of 185 (5.9%) subsequent urine samples from these 21 treated animals and serotype pomona was cultured from the kidney of 1 of the 10 animals that were examined from this group at slaughter.

Following the initial detection of leptospiruria in the 16 un-treated pigs, 179 of 211 (84.8%) subsequent urine samples con-tained leptospirae, which were also cultured from the kidneys of 4 out of 11 of these animals.     

Some observations on the liver copper status of pigs in the northern part of New Zealand

The copper content of the livers from 347 pigs was analysed. Two hundred and three of these samples were from animals varying in age from full term foetus to five years, which were submitted to the laboratory (laboratory cases) for a variety of diagnostic tests. The remaining 144 liver samples were obtained from pigs slaughtered at an abattoir (abattoir survey) at 75-S kg liveweight (approximately 20–30 weeks old).

Liver copper levels of 12 mg/kg D.M. (Dry Matter) or less, a level consistent with copper deficiency, were found in 6.9% of the laboratory cases and in 9.0% of the abattoir survey pigs. Liver levels less than 20 mg/kg suggesting insufficient dietary copper to produce a growth-promoting effect, were found in 21.6% of the former and 36.1% of the latter pigs.

A significantly greater frequency of illthrift and anaemia was found in the laboratory cases in which liver copper levels were less than 20 mg/kg compared with animals with higher levels. Liver copper levels less than 20 mg/kg were also more common in pigs derived from dairy farms or fed garbage than in animals from pig farms or fed on meal.

All of 26 samples of commercial pig meal analysed contained sufficient copper to satisfy the daily essential copper requirements of pigs (greater than 5–6 mg/kg) but 14 of these (53.8%) contained less than 125 mg/kg levels of copper and were unlikely to produce a growth-promoting effect.     

Clinical and biochemical changes in sheep inoculated with leptospira interrogans serotype pomona

Clinical and biochemical changes occurring in whole blood, urine, plasma and serum of sheep experimentally infected with Leptospira interrogans serotype pomona were studied.

Half-time and fractional clearance rates of sulphobromophthalein, phenosulphophthalein and chromium (^5lCr) EDTA were also measured to assess functional damage to the liverand kidney.

The results suggested that the biochemical changes occurring following pomona infection were due mainly to haemolysis of erythrocytes and to mild impairment of tubular and glomerular kidney function. No alteration in liver function was observed: Analyses of isocitrate dehydrogenase, arginase, and total bilirubin in serum and measurements of kidney glomerular and tubular function appeared to be the most useful biochemical indicators of pomona infection in sheep.     

Yersinia pseudotuberculosis recovered from the faeces of clinically healthy deer

Extract

Sir:— A recent paper by Henderson and Hemmingsen(1) reported the recovery of Yersinia pseudotuberculosis from the faeces of 5 of 3810 (0.13%) clinically healthy deer in a national survey conducted on 122 farms. The isolates were obtained from animals on four (3.27%) different farms. The authors concluded on the basis of these results and unpublished data that Y. pseudotuberculosis was only rarely recovered from faeces of healthy deer.     

Livestock, ethics, and quality of life

Agricultural and animal scientists need to embrace a new vision beyond the single-minded existing pursuit of biological efficiency. The public in the West is no longer concerned solely with cheap food. Other paramount issues define quality of life, including: health and safety of foods; nutritional value; traditional, regional, locally produced, and organic foods; animal welfare; sustainable farming, environment, and rural resources. The paper provides examples of how the credibility of animal scientists has been lost due to some recent unethical behavior. Research, teaching and application of agricultural and animal science, especially of biotechnology, need to be reshaped into a new "Quality of Life Agricultural Era" to replace the "Era of Intensification." This new era will need fresh assumptions, beliefs and leadership to match the emerging social agenda of the 21st century. Animal scientists have a special role in implementing this new plausibility structure.