1. A study was made of the milking of the two hind quarters of four cows by teat cup and by teat cannula at three levels of vacuum and by teat cannula at atmospheric pressure.2. The eight quarters milked at significantly different maximum rates by teat cup but at nearly the same rate through a teat cannula, suggesting that the teat orifice is a very important factor controlling rate of milking.3. The maximum rate of milking by both teat cup and teat cannula increased with increasing level of vacuum from 11 to 20 in. Hg. The rate of increase in the teat-cup milking was greater than in the cannula milking, suggesting that the teat orifice was stretched open at the higher levels of vacuum.4. The average amount of strippings increased at the higher level of vacuum in teat-cup milking, due apparently to teat-cup crawl.

1. Results are reported from two experiments in a series to determine the optimal amount of meal to be fed in conjunction with unrestricted whey for fattening pigs.2. In both experiments, one carried out during the summer and the other during the winter season, the same four treatments were given. The control pigs received meal ad. lib up to a maximum of 6½ lb./ head daily. Pigs on the other three treatments received whey ad lib., and either 3 lb., or 3 lb. reduced at two different stages to 2 lb. of meal per head daily. There were ten pens of nine pigs on each treatment, involving a total of 360 pigs. Comprehensive carcass measurements were made on all pigs.3. The data obtained showed that satisfactory results could be obtained by feeding a daily allowance of 3 lb./pig of a proprietary sow and weaner meal throughout the fattening period, in conjunction with unrestricted whey. Where the utilization of as much whey and as little meal as possible was required, it was shown that a reduction from 3 to 2 lb. meal/pig/day by the 13th week of life could be made without adverse effects, apart from an increase of approximately 12 days in the time taken to reach bacon weights.4. Carcass grading results of all whey-fed pigs were reasonably satisfactory, but both the carcass grading and general performance of the control animals was not good. Possible reasons for this were discussed.5. Data concerning the pattern of food consumption over 14-day periods throughout the experiments were presented. Pigs given 3 lb. of meal/day throughout, or 3 lb. reduced to 2 lb./day, consumed up to approximately 3¼–3½ or 3¾–4 gal. of whey/day respectively.

1. A survey and. statistical analysis of the records of litters born in the N.I.R.D. herd of Large White pigs over a period of 16 years are presented.2. The mean length of gestation was 114 days for both gilts and sows.3. The mean numbers of pigs born alive and born dead per litter from gilts, 10·0 and 0·2 respectively, were both significantly smaller than the corresponding figures for sows, 11·8 and O·8. No seasonal differences were found.4. The mean total losses of pigs from birth to weaning at 8 weeks were 29·5% of pigs born alive. The losses in litters from gilts, 23·0%, were significantly smaller than in litters from sows, 31·0%. The losses during the winter months both for gilts, 32·5%, and for sows, 35·9%, were significantly higher than during the summer months, 19·4% and 26·7% for gilts and sows respectively.5. Over 50% of the total losses were due to crushing by the dam, 74·1% of the losses from this cause occurring during the first 48 hr. after birth.6. The mean number of pigs weaned per litter was 8·0. The difference between the number weaned per litter from gilts, 7·7, and per litter from number of pigs was weaned per litter from sows during the summer months, 8·7, than during the winter months, 7·4.7. There was no significant difference between the number of male and of female pigs weaned.8. The mean weight at weaning was 29·9 lb., male pigs, 30·3 lb., being significantly heavier than females, 29·51b. Pigs in litters from gilts, 27·81b., were significantly lighter at weaning than those from sows, 30·0 lb., and for both gilts and sows, pigs reared during the summer months, 29·7 and 31·8 lb. respectively, were significantly heavier than those reared during the winter months, 25·9 and 28·2 lb. respectively.

SUMMARY: On exposing a strain of Bacterium coli 28.D.10 in a surface film at atmospheric temperature to atmospheres of different moisture contents, it was found that for relative humidities between 100 and 66% the numbers of survivors decreased with decreasing humidity. There was also some evidence of a slight increase in survivors for a decrease in relative humidity from 43 to 0%. The percentage of survivors of Bact. coli after exposure to quaternary ammonium disinfectants also decreased with relative humidity between 100 and 66% but no significant differences were found for changes in relative humidity below 66%. The numbers of survivors of a culture of Staphylococcus aureus were the same after storage at a relative humidity of 43% as at 100%; drying did not appear to affect the sensitivity of Staph. aureus to quaternary ammonium compounds. Tests of the effect of storage time in a saturated atmosphere gave results which were not entirely consistent, but where differences were observed, there was a lower percentage of survivors for freshly inoculated films than for films which had been stored for 3 hr, presumably because a fresh film was more easily removed to the disinfectant. When either Bact. coli or Staph. aureus was exposed to a disinfectant, the percentage of survivors was higher when the organisms were in a surface film than when they were inoculated directly into the disinfectant. Agitation during exposure reduced the numbers of survivors from a surface film. Neither the glass nor the metal coming in contact with the disinfectants affected the level of survivors. Under the conditions of testing, sodium hypochlorite was a more effective disinfectant than the quaternary ammonium compounds used.

The response of rabbit mammary glands to intraductally-injected prolactin preparations has been investigated with a view to developing an assay procedure for prolactin, based on milk formation in mammals. Milk was clearly detectable in the glands by the 3rd day after injection of prolactin, and there was evidence of an increase in response with increased dose, but the variability so far encountered has been high. Intraductal injection of pituitary extracts rich in activities other than that of prolactin did not lead to milk formation.