Lambs were fed diets in which peat replaced equivalent alfalfa hay. Gains were depressed by proportionately 0·14, 0·32 and 0·56 due to 100, 200 and 300 g peat per kg, respectively, during a 63-day feeding period. Lambs fed peat required more dry matter per unit gain. Necropsy examination of heart, kidney, liver, spleen, lung, and pancreas revealed no gross abnormalities from feeding of peat. Rib eye area was reduced at 200 and 300 g dietary peat per kg. There were no differences in taste of cooked loin sections due to peat. These studies support the safety of feeding peat for use as a dietary carrier at 20 to 30 glkg diet or as a dietary diluent at higher levels.

The effects of monensin sodium, administered by intraruminal controlled-release devices at a rate of 320 mglday, on milk and milk solids production and bloat score were examined in a trial with 90 lactating dairy cows given only mixed ryegrasslwhite clover pasture. Monensintreated cows had significantly greater yields of milk and milk protein than control cows (1397·2 (s.e. 22·9) v. 1296·9 (s.e. 16·3) kg milk, 49·6 (s.e. 0·9) v. 46·5 (s.e. 0·6) kg protein) over the 14-week period of treatment (P < 0·01). Yield of fat was similar in monensin-treated and control cows (62·9 (s.e. 1·5) v. 63·4 (s.e. 1·1) kg). Live weight, condition score and bloat score were not influenced by treatment but pasture conditions were not conducive to severe bloat challenge.

Eight mature Dorset-cross sheep, each fitted with a permanent rumen cannula, were given a diet of chopped barley straw (plus urea and minerals) either with or without an Aspergillus oryzae (AO) fermentation extract (2 glday). The addition of AO fermentation extract to the diet increased the initial rate of straw degradation (P < 0·05) but did not alter the final extent of degradation. Total culturable bacteria increased with AO treatment but numbers of cellulolytic bacteria, ciliate protozoa, and aerobic fungi, were not significantly altered. Rumen pH, liquid clearance rate, total volatile fatty acids, acetate, propionate, butyrate, L-lactate and ammonia concentrations were also unaffected.

One hundred and five Holstein cattle, with a mean body weight of 668 kg, were superovulated using a total dose of 18 mg FSH. Five animals did not have corpora lutea (CL). No ova or embryos were recovered from 12 of the 100 animals which had CL. A total of 810 ova/embryos were collected from the remaining 88 animals and 432 of these were of transferable quality. The mean (range) measurements for subcutaneous fat deposition in samples taken at slaughter from the back, rump and ventral abdominal wall were 14 mm (3 to 34), 7 mm (0·7 to 33) and 7 mm (0·8 to 32), respectively. The number of transferable embryos and fertilized ova decreased as fat levels increased, but the differences between the groups were not significant (P > 0·05). There was a positive relationship between the number of CL and (a) the number of fertilized ova, and (b) the number of transferable embryos (r = 0·53, P < 0·001 and r = 0·48, P < 0·001). The correlation between the number of fertilized embryos and the number of transferable embryos was r = 0·91, P < 0·001.

The Effect of the Plane of Nutrition on the Optimum Dietary Amino Acid Pattern for Growing Pigs

T. C. Wang and M. F. Fuller

Volume 50, Part 1, page 157

FIG. 1 — The letters A and C on diagram should be reversed