An automatic rising plate meter called the Ellinbank Pasture Meter (EPM) was constructed and evaluated at the Dairy Research Institute (Ellinbank) for measuring the dry matter present on a pasture dominated by green perennial rye grass. The meter readings of pasture height were found to correlate linearly with pasture yield, and the coefficient of variation of calibrations on any one date averaged about 13%. When the data from a large number of calibrations from separate dates were pooled, the coefficient of variation increased to about 18% (RSD 370 kg ha-1). Although there was a high level of repeatability of readings within operators, a substantial degree of variation existed between operators. The diurnal variation in dry matter percentage of pasture had only small effects on the meter readings. The EPM has an advantage over other pasture measuring methods in that its automatic function enables up to one hundred pasture measurements to be made in five minutes. In direct comparison with a manual rising plate meter and a two probe electronic capacitance meter, it was found that there was no significant difference in accuracy between the three meters but the advantages of the EPM are discussed. On perennial rye grass/white clover pastures in an actively growing vegetative state, the EPM has been found to be accurate enough for research purposes yet simple enough for use by farmers and their advisers as an aid to pasture management.
The present study demonstrated a prolonged lag phase and delayed gastric emptying in obese women when compared to lean women. This delay may be as a consequence of high-fat diets, a sedentary lifestyle and increased gastric distension associated with obesity, or a contributing factor in the pathogenesis of obesity resulting from the inactivation of gastrointestinal satiety signals and in an increase in food intake.
Eight samples of perennial ryegrass-white clover herbage with in vivo dry matter digestibility (DMD) ranging from 0-579 to 0-764 were used to evaluate various cost-saving modifications to the two-stage pepsin-<;ellulase digestibility technique. The effect of sample size, celluiase quality, cellulase/sample ratio, digestion time and washing of residue following digestion were investigated. The loss of dry matter (DM) in the assay was correlated with in vivo DMD and each variation of the method was evaluated by comparing the s,d, between replicates and r,s,d, of the regression, as well as the convenience of the method for large-scale monitoring of digestibility of mixed ryegrass-clover herbage.It was found that the amount of celluiase used could be reduced by a factor of 25, compared with recently published methods, without increasing s.d, or r,s,d, appreciably. In addition stirring during digestion and washing of the residue could be omitted without any deleterious effects. Increasing digestion time did not reduce s,d, or r,s,d, and the low-grade celluiase proved to be slightly more economical.Increasing the sample size from 0-25 to 0-50 g improved the s,d, and r,s,d, but the residues from the larger samples were generally slower to filter, which made the assay unsuitable for routine use.Substantial reduction of digestion volume and use of a thermostatically controlled water bath instead of an incubator led to a considerable increase in efficiency and throughput of samples. Stirring the samples during digestion was found to be unnecessary, thus allowing more flexibility in the laboratory routine, for example using the weekend for digestion. Using the recommended method modification the repeatability between replicates and r,s,d, of the calibration regression was 0-004 and 0-015 respectively for samples ranging in DMD from 0-579 to 0-764,
Two experiments were carried out to measure effects of body condition at calving and different levels of feeding after calving on milk and subsequent reproduction.In experiment 1, which was conducted in two consecutive years, 162 cows (77 in year 1 and 85 in year 2) were group feed so as to reach a target body condition (condition scores ranging from 3-6) four weeks before calving. During the last four weeks before calving, all cows were managed so as to maintain their individual condition scores. At calving, cows in similar condition of similar breed and with similar previous milk production were allocated to high and low levels of feeding at pasture for the first five weeks of lactation. Mean pasture intakes were 13.0 and 7.0kg dry matter (DM)/cow.d in year 1 and 15.0 and 8.5 kg DM/cow.d in year 2In experiment 2, 40 cows were offered pasture and hay from 20 weeks before calving to achieve a body condition score of either 4 or 6 by two weeks before calving. During the first five weeks of lactation, cows were individually fed in stalls on freshly cut pasture at one of three levels of intake, 7 or 10 kg DM/cow.d or .In both experiments cows were grazed as one group from week 6 to 20 of lactation.Improved body condition at calving resulted in an extra 4.0, 11.0 and 7.4 kg milk fat per unit condition score over 20 weeks of lactation, for year 1 and 2 of experiment 1, and experiment 2, respectively. Cows in poorer condition partitioned a higher proportion of feed energy to liveweight at the expense of milk production than did the cows in better condition. However, increasing the plane of nutrition in early lactation resulted in higher levels of milk production and reduced the need for cows to mobilize bodyreserves. Improved body condition at calving had a positive effect on milk fat percentage, particularly in early lactation, but did not affect milk protein percentage. Input-output relations calculated from the experimental data showed that the benefit sf to improve body condition before calving was less than that of additional feeding after calvin changes in the condition of the cows were taken into consideration (25.8 vs 1 4.6 kg DM to yi kilogram of milkfat). Improvements in condition and feeding in early lactation reduced the anoestrus interval after calving by 5.7 d for each additional condition score at calving and 1. d for each additional kgDM/cow.d fed over weeks 1-5 of lactation. The input-output relations resented will enable farmers to assess the likely consequenes of changes in their feeding management in the crucial peripartum period with a greater degree of confidence than in the past.
Abstract. Experience with browse plants in Australia is briefly reviewed in terms of their forage value to animals, their economic value to the landholder and their ecological contribution to landscape stability. Of the cultivated species only two have achieved any degree of commercial acceptance (Leucaena leucocephala and Chamaecytisus palmensis). Both of these are of sufficiently high forage value to be used as the sole source of feed during seasonal periods of nutritional shortage. Both are also leguminous shrubs that establish readily from seed. It is suggested that a limitation in their present use is the reliance on stands of single species which leaves these grazing systems vulnerable to disease and insects. Grazing systems so far developed for high production and persistence of cultivated species involve short periods of intense grazing followed by long periods of recovery. Similar management may be necessary in the arid and semi-arid rangelands where palatable browse species are in decline.
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