The intestinal flora of the chicken in the period 2 to 6 weeks of age, with particular reference to the anaerobic bacteria

A study has been made of the intestinal flora of chickens aged between 2 and 6½ weeks. No major differences were found when rations containing 9 or 25% fish meal were compared or when two different sources of fish meal were used. Throughout the period investigated, it was confirmed that the lactobacilli are the only group of organisms generally present in the small intestine in numbers exceeding 104/g. Clostridia were regularly found at 102 to 104/g, but Clostridium welchii was isolated from only occasional samples.

In the caeca, the total number of bacteria present at 2, 3, 4 and 6½ weeks was about 1011/g. Of these it was generally possible to isolate more than 20% using an anaerobic roll‐tube technique and oxygen‐free CO2. Many different types of anaerobes were isolated including strictly anaerobic budding bacteria which had not previously been studied. During the growth of the bird the flora changed. Anaerobic streptococci (peptostreptococci) predominated at 2 weeks but gradually decreased so that by 6½ weeks these organisms formed only a small part of the flora. Many of the Gram‐negative non‐sporing anaerobes only appeared between the 4th and 6th weeks.

Throughout the 2 to 6½‐week period all the caecal samples examined contained 108 to 109 anaerobes/g which were able to attack uric acid and sometimes 1010/g. This property was shared by at least one group of peptostreptococci, four groups of Gram‐negative non‐sporing anaerobes, three groups of Gram‐variable or Gram‐positive anaerobic non‐sporing rods and several species of clostridia.     

The microbiology and sensory evaluation of pheasants hung at 5, 10 and 15 degrees C

Pheasants hung for 9 d at 10 °G were found to be more acceptable than those hung for 4 d at 15 °G or for 18 d at 5 °G. The birds stored at 15 °G were tough by comparison with those held for longer at the lower temperatures and the clostridia, including Clostridium welchii, increased considerably in the intestines during the storage period. Microbial growth in the muscle tissue was generally found to occur only in birds in which the gut had been perforated by shot. There is an indication that 9 d at 10 °C produced a more “ gamey “ bird than 18 d at 5 °G or 4 d at 15 °G, but the most “ gamey “ birds, independent of temperature, were those in which the muscle was damaged by shot.     

An Economic Appraisal of President Carter's Energy Program

An analysis of 11 major federal energy policies of the last half-century indicated a record of conflicting and counter-productive government policies. These policies contributed heavily to the energy crisis. The essence of the President's energy plan is more government interference and less reliance on the price system. Crude oil price controls are to become permanent, and natural gas price controls are to be extended. This requires that government decide who gets the low-priced energy, who pays high prices, and who increasingly goes without. Government energy policies have historically reflected dominant organized pressures.     

Factors affecting the survival of Campylobacter jejuni in relation to immersion scalding of poultry

Potential measures for reducing the survival of campylobacters during commercial scalding of poultry have been evaluated in a series of laboratory trials. At 50 degrees C, the lower temperature limit of commercial scalding, raising the pH of a buffered heating medium from 6.0 to 9.0 markedly increased the heat sensitivity of Campylobacter jejuni but the effect was largely nullified in the presence of 1 per cent 'organic material' (50:50 horse blood and milk). Either in the presence or absence of organic material a more rapid rate of kill was observed at 60 degrees C and it was again enhanced by raising the pH to 9.0. Use of a mild detergent at a concentration of 1000 ppm had little effect on the survival of C jejuni at 50 degrees C, but the addition of a cationic quaternary ammonium product at 50 to 100 ppm was highly effective in enhancing the rate of kill, even in the presence of organic material. It is suggested that such products should be evaluated in commercial scalding systems as a possible means of preventing the spread of campylobacters and other organisms of significance to public health.     

The bacteriological condition of eviscerated chickens processed under controlled conditions in a spin-chilling system and sampled by two different methods

Quantitative changes have been determined in the flora of chicken carcasses after passage through a series of three separate spin‐chillers. The majority of organisms were eliminated from the chill‐water during processing by using 1.7 1 of water per carcass and 45 to 50 ppm of total residual chlorine in the first two chillers and 1.0 1 of water per carcass and 25 to 30 ppm of residual chlorine in the third chiller.

Total viable counts at 20 and 37 °C and levels of coli‐aerogenes bacteria obtained from the rinsing of whole carcasses were reduced by more than 90% during chilling. Results obtained both with and without the use of chlorination compared favourably with those claimed for other chilling systems. It was concluded that the main effect of chlorination in the chillers was to destroy organisms washed from the carcasses, thus avoiding recontamination.

A comparison of two different sampling methods showed that maceration of neck‐skin usually gave higher counts of both faecal and spoilage bacteria after chilling than the rinsing of whole carcasses.     

Microbiological changes in the uneviscerated bird hung at 10 degrees C with particular reference to the pheasant

Thirty pheasants which had been reared in captivity for 19 weeks were killed by dislocating the neck and hung for up to 15 d at 10 °C. Microbiological, sensory and chemical assessments were made at 0, 3, 6, 8, 10, 13 and 13 d and this paper reports the microbiological results.

Examination of the duodenum, small intestine and caecum showed very little multiplication of coli‐aerogenes bacteria during hanging, although there was some increase in the numbers of faecal streptococci. Psychrophilic clostridia, mainly Clostridium putrefaciens, were found in the small intestine after 8 d and these organisms increased in number up to the 15th d.

The muscle remained relatively free from bacteria for most of the hanging period, but at 15 d Cl. putrefaciens was found in two out of three muscle samples at io³ and io⁴ per g.

No signs of spoilage due to greening were observed.

Twelve 16½>‐week‐old chickens were also killed by dislocating the neck and hung without plucking for 12 d at 10 °C with the pheasants. Although initially there were no major differences between the intestinal flora of the chickens and pheasants, faecal streptococci and coli‐aerogenes bacteria multiplied rapidly in the small intestine of the chickens during the first week. Greening occurred around the vent within 5 d.

Reasons for the differences between the two types of bird are discussed, particularly in relation to the diet.     

Dog-associated risk factors for human plague

Plague is a rare but often fatal zoonosis endemic to the western United States. Previous studies have identified contact with pets as a potential risk factor for infection. We conducted a matched case-control study to better define the risks associated with pets at both the household and individual levels. Using a written questionnaire, we surveyed nine surviving plague patients, 12 household members of these patients, and 30 age- and neighbourhood-matched controls about household and individual exposures. Overall, 79% of households had at least one dog, 59% had at least one cat and 33% used flea control, with no significant differences between case and control households. Four (44%) case households reported having a sick dog versus no (0%) control households [matched odds ratio, (mOR) 18.5, 95% confidence interval (CI) 2.3-infinity], and four (44%) patients reported sleeping in the same bed with a pet dog versus three (10%) controls (mOR 5.7, 95% CI 1.0-31.6). Within case households with multiple members, two (40%) of five patients slept with their dogs versus none (0%) of 12 healthy family members (P=0.13). The exposures to cats were not significant. Sleeping in the same bed as a pet dog remained significantly associated with infection in a multivariate logistic regression model (P=0.046). Our findings suggest that dogs may facilitate the transfer of fleas into the home and that activities with close extended contacts with dogs may increase the risk of plague infection.