SUMMARY1. The primary growth of a sward of S24 perennial ryegrass was harvested between 23 April and 9 May 1968, artificially dried and either chopped or coarsely milled. The two physical forms of grass were wafered either alone or together with 50% by dry weight of rolled, anaerobically stored barley, and given to 7-month-old, Hereford × British Friesian steers in an experiment of 2 × 2 factorial design.2. A representative group of animals was slaughtered at the beginning of the experiment, and the remainder were individually fed ad libitum for 70 days, after which they also were slaughtered. During the feeding period digestibility was determined by total faecal collection from all the animals individually on two occasions.3. Dry-matter intake and live-weight gain were similar on all feeds. The weight of gut contents as a percentage of final live weight was significantly lower and the carcass-weight gain was significantly higher for animals given wafers containing barley compared with those for animals given wafers of grass alone.4. Coarse milling compared with chopping reduced the apparent digestibility of dry matter, organic matter, cellulose and energy; the addition of barley increased the digestibility of organic matter but further reduced that of cellulose.5. The efficiency of conversion of digested energy to empty-weight or carcass gain was similar for wafers containing the two forms of forage, but the digested energy of wafers containing barley was converted to carcass weight with significantly greater efficiency than that of wafers consisting solely of grass.6. Physical separation of the tissues of sample joints failed to show any significant differences in the proportion of fat, muscle and bone as a result of either differences in physical form or the inclusion of barley.7. The results indicate that live-weight gain is an insufficiently sensitive measurement by which to assess the true productive potential of feeds given to ruminants in short-term experiments.

The effect of whole crushed rapeseed on ration digestibility was determined with three bulls, average live weight 155 kg, and the effect on rumen fermentation with a heifer fitted with a rumen fistula. The basal diet (B) contained 50 % of grass silage and 50 % of rolled barley of total DM. In experimental diets 30 % of barley was replaced with crushed rapeseed fed either untreated (URS) or treated with 1.2% of Gasol solution (GRS). The feeding level was 80 g DM/kg W0.75 for the bulls and 60 g DM/kg W0.75 for the heifer. The average digestibilities of the diets were 73.9 (B), 71.6 (URS) and 72.7 % (GRS) for organic matter. There were no significant differences in apparent digestibility of crude protein or crude fibre. The digestibility of ether extract was higher (P < 0.05) and that of NFE lower (P < 0.01) on rapeseed diets. Nitrogen retentions were 28.4, 30.9 and 33.7 g/d, respectively, for the three treatments. On rapeseed diets the rumen pH was higher (P < 0.05) and the total VFA and ammonia N concentration lower (P < 0.01, P < 0.05) than on control diet. Rapeseed increased the proportion of propionic acid (P < 0.01) and decreased the proportion of butyric acid (P < 0.01) in rumen VFA. The rate of degradation of DM and CP in the rumen was slower for Gasol-treated rapeseed than for untreated rapeseed. Rapeseeds did not have a negative effect on the rate of degradation of silage or hay in the rumen determined by nylon bag method. But replacement of barley with rapeseed tended to decrease the degradation rate of silage crude protein. There were no significant differences between the treatments in blood constituents.

Fungal glucose oxidase and cellulase were used as silage additives in laboratory (25 l), pilot (3 m3) and farm scale (250 t) silos. In 3 m3 scale silos, pH and the concentration of acetic acid were lower and the concentrations of lactic acid and sugars were higher in the enzyme treated than in untreated silage. The concentration of butyric acid was equal to or lower than in formic acid treated silage in all experiments. Cell wall constituents were degraded in the silo by cellulase and thus more energy was available for lactic acid bacteria. With increasing levels of cellulase application, the disappearance of organic matter (OM) from nylon bags incubated for 1 to 12 h in the rumen of a dairy cow increased significantly (P

Grass silage was offered ad libitum to 16 Ayrshire cattle in a 2 x 2 factorial experiment lasting 196 days. The silage was supplemented with barley preserved with 0.85 % of propionic acid (PAB) or 1.28 % Gasol solution (GB) 45 g DM/kg W0.75. Four of the animals in PAB and GB groups received no protein supplement(NPS) and four of the animals in both groups received extracted rapeseed meal as protein supplement(RSM). RSM was fed according to UDP (undegradable feed protein) requirements. The average age of the animals at the beginning of the experiment was 86 days and the average liveweight 106 kg. The average daily gains were 1066 and 1070 g/d for PAB and GB groups and 1012 and 1124 g/d (P < 0.01) for NPS and RSM groups. In feed intake and feed conversion there were no significant differences between the groups. Supplementation of silage barley diet with RSM increased the digestibility of organic matter from 71.1 to 73.5 % (P < 0.05), of crude protein from 62.8 to 67.4 % (P < 0.05) and of crude fibre from 57.2 to 60.2 % (P < 0.05). Both barleys were well preserved and there was no deterioration during the storage. The degradation rates of DM, crude protein and starch determined by nylon bag method were lower in GB than in PAB. Crude protein disappearances in 9 hours were 46.6 % for GB and 76.4 % for PAB. The utilization of absorbed protein calculated by factorial method averaged 0.566 ± 0.01 in the four different groups. Plasma urea N level was higher (P < 0.05) in the RSM than in the NPS group. The proportion of acetic acid in the rumen VFA was lower (P < 0.05) and that of propionic acid higher (P < 0.01) in the RSM than in the NPS group. PAB resulted in a higher (P < 0.05) proportion of propionic acid in rumen VFA than did GB.

Abstract. This study investigated the effect of a polyol mixture or molasses treated beet pulp on the feed utilization, milk yield and blood values. 24 cows were divided into 3 groups. Hay was given at 2 kg/d, silage ad lib. and concentrate mixture at 7 8 kg according to the milk yield. The control group had grain (barley-oat) concentrate mixture, the molasses group had grain supplemented with 29 % dried molasses beet pulp and for the polyol group grain was supplemented with 25 % dried beet pulp treated with mixture of sugar alcohols.A 2 weeks standardisation period was followed by 12 of comparison. 12 of the cows were also in a digestibility trial in the later part of the comparison period.Feed intake was heavily reduced in the molasses group and hence the milk yield was significantly lower (P < 0,05) than in the polyol or control groups (19,5, 21,2 and 21,2 kg FCM/d). The mean consumption of polyols was 483 g/d and that of sugars from the molasses beet pulp was 410 g/d.The feed utilization was significantly lower (P < 0,05) in the control group than in the polyol or molasses groups. The consumptions of f.f.u./kg FCM were correspondingly 0,407, 0,375 and 0,373.Digestibility of nitrogen free extracts was significantly higher for the polyol group than for the control group (81,4 and 78,1 %). For molasses group digestibility of NFE was 78,5 %. Digestibility of OM was correspondingly 76,2, 73,6 and 74,3.Rumen butyric acid formation was higher in the polyol group than in the molasses or control groups, although the differences were not statistically sinificant.The blood and plasma parameters studied were haemoglobin, PVC, ketone bodies in blood, glucose, total protein, urea-N and uric acid in plasma.Plasma urea-N was higher (P < 0,01) in the control than the polyol or molasses groups. In glucose or ketone bodies concentration there were no treatment induced differences.