Studies on the cutting management of grass-clover swards Part II. The effects of close cutting with either a gang mower or a reciprocating-knife mower on the yields from an established grass-clover sward

1960 ◽  
Vol 54 (2) ◽  
pp. 158-165 ◽  
Author(s):  
D. Reid ◽  
D. S. MacLusky

1. In an experiment conducted on an established perennial rye-grass/white clover sward close cutting was carried out over a 3-year period (1956–58), either with a lawn mower to simulate gang mowing or with a reciprocating-knife mower. The sward was cut either six or eight times in each season, and received 0 or 2 cwt. ‘Nitro-Chalk’/acre for each cut.2. Swards cut with the gang mower yielded from 3·5 to 12·5% more herbage dry matter than swards cut with the reciprocating-knife mower and also gave a greater mean yield of crude protein.3. The difference in dry-matter yield between swards cut with each of the mowers is attributed to the slightly closer cutting level of the gang mower having a greater inhibiting effect on flower development in the grasses and hence stimulating leaf production and increasing total yields.4. In the second and third years of the experiment swards cut with the gang mower outyielded those cut with the reciprocating-knife mower by a proportionately greater amount when eight cuts rather than six cuts were taken in the season.5. When no nitrogenous fertilizer was applied the proportion of broad-leaved weeds in the sward increased more rapidly over the 3-year period where the herbage was cut with the gang mower rather than the reciprocating-knife mower. This disadvantage of gang mowing did not apply where the fertility was maintained at a high level by applications of nitrogenous fertilizer.6. It is concluded that the gang mower is a more suitable machine than the reciprocating-knife mower for close cutting on a field scale.

1987 ◽  
Vol 67 (3) ◽  
pp. 735-746 ◽  
Author(s):  
P. GERVAIS ◽  
J. M. GIRARD

A 3-yr study on height and frequency of cutting showed that alfalfa (Medicago sativa L.) cut at 5 cm from the soil produced significantly more dry matter per hectare than that harvested at 10 cm, but the differences between the two heights decreased with the years and the frequency of cutting. Forages cut at either height had similar mineral composition at any one cutting. However, the percentages of cell walls and of lignocellulose were, in general, highest in alfalfa cut at 5 cm. Height of cutting did not affect the stand nor the accumulation of food reserves in the roots in the fall. The two-cut system gave a uniform production from year to year and maintained the stand at a high level. The three-cut system, the last cut taken in October, yielded the highest yields of dry matter and of crude protein while the four-cut system produced the least and had the thinnest stand at the end of the experiment. Frequency of cutting gave rise to significant variations in the chemical composition of the forages, variations resulting from the difference in the stages of growth at harvest. In general, alfalfa cut at a younger stage exhibited a more valuable composition than that harvested at a later stage. Food storage in the roots varied with frequencies, being highest with the two-cut system and lowest with the four-cut system.Key words: Alfalfa, height and frequency of cutting, yield, chemical composition, food reserves


1972 ◽  
Vol 52 (6) ◽  
pp. 941-948 ◽  
Author(s):  
L. B. MacLEOD ◽  
H. T. KUNELIUS ◽  
F. W. CALDER

The effects of early summer and fall cutting managements on two alfalfa (Medicago sativa L.) cultivars were studied over a 3-year period. Removal of the first crop of Saranac and Narrangansett alfalfas at prebud stage, followed by two cuts at the early bloom stage before early September, and a late fall harvest on October 25, produced seasonal dry matter (DM) yields of 7.5–8.6 metric T/ha in the 1st year. Stand deterioration, however, was severe and by the 3rd year, practically all alfalfa had disappeared. Average percent crude protein (CP) in cut 1 was 17.7–21.9 and percent in vitro dry matter digestibility (IVD) 67.4–73.8. Removal of the first cut at bud stage with two subsequent harvests at the early bloom stage also allowed a total of three harvests before early September and resulted in seasonal DM yields of 8.6–8.8 in the 1st year. Although the survival of alfalfa was increased over the managements where cut 1 was at prebud stage, a considerable decrease of alfalfa was still observed in the 3rd year. Under this management, average CP in cut 1 was 15.8–16.3 and IVD 64.1–68.4. Harvesting the first crop at early to midbloom stage and the second crop at early bloom in early to mid-August, followed by third harvest in late October, resulted in good survival with seasonal DM yields of 6.1–10.6. Lower CP and IVD were recorded in cut 1 than in the more intensive managements. Under all managements, average CP in cuts 2 and 3 was 14.9–17.3 and 13.3–19.4, respectively. IVD was 54.5–60.7 in cut 2 and 56.0–64.4 in cut 3.


Author(s):  
K. I. Khidirov ◽  
◽  
G. J. Kutlieva ◽  
B. I. Turaeva ◽  
N. A. Elova ◽  
...  

Research has been carried out to study the influence of "ProBioKorm Uz", a biologically active feed additive, on the development and physiological characteristics of rabbits of ‘New Zealand’ breed. During the experiment, 2 experimental and a control groups were formed. Adding "ProBioKorm Uz" to the main feed at the rate of 1% and 2% had an increase in experimental group rabbits’ live weight. Average live weight of them was higher by 5,7 %-3.8% than in the control group. Feed units composed 1.59%, dry matter 0.56 kg (3.61%) and crude protein 0.11 kg (3.59%) compared with the control group. Rabbits of experimental groups had higher indicators of erythrocytes concentration by 0.34-1.00 1012/l (10.34-19.53%), leukocytes - by 0.370-0.46 109/l (5.66-8, 06%), as well as a high level of hemoglobin by 7.42-11.08 g/l (6.81-10.08%) and total protein - by 2.40-4.48 (3.64-6, 42%).


1958 ◽  
Vol 50 (1) ◽  
pp. 49-59 ◽  
Author(s):  
D. G. Morgan ◽  
G. C. Mees

1. Field trials with gibberellic acid on grass, wheat, potatoes, turnips, carrots, peas, runner beans, lettuce, celery, blackcurrants, kale and maize are described. The effects on plant growth and crop yield were determined.2. The experiments on grassland were carried out between July 1953 and June 1956, and included trials at four different centres. They all gave essentially similar results.3. 2 oz. per acre of gibberellic acid sprayed at 100 gal. per acre stimulated the growth of all components of the swards. The stimulation was most clearly seen in spring and autumn when the natural growth rate was slow. At these times gibberellic acid was able to produce a grazeable growth of grass more rapidly than nitrogenous fertilizers. The stimulation of growth was accompanied by yellowing of the grass, but recovery to a normal green colour was speeded up by applying a nitrogenous fertilizer at the same time as the gibberellic acid spray.4. The dry-matter yields at the first cut following a treatment with gibberellic acid were increased by 0·6–10·8 cwt. per acre. The crude protein yields were also increased by the treatment, but to a relatively smaller degree, and the protein content of the grass was reduced by between ½ and 2%. The contents of phosphorus, potassium, sodium, calcium, barium, magnesium, manganese, copper, aluminium and tin were not altered.


1951 ◽  
Vol 41 (3) ◽  
pp. 282-287 ◽  
Author(s):  
M. E. Castle ◽  
A. S. Foot ◽  
S. J. Rowland

For three consecutive years American hybrid maize was grown, under replicated experimental conditions, in the south of England. Each season, the influence of the spacing of the plants and the use of nitrogenous fertilizer on the yield and composition of the crop and of its separate portions of leaf, stem and cob was investigated.The growth of the maize, and especially its yield of dry matter, were influenced by the weather conditions during the season. The weight of fresh crop varied, with season and treatment, from 126 to 278 (averaging 209), and of dry matter from 20 to 70 (averaging 50) cwt./acre.Thinning below the established plant populations of up to 30,000 plants per acre regularly reduced these yields. Top-dressing with sulphate of ammonia increased them in 1947 and 1949, but decreased them in 1948.The yield of crude protein varied from 2.2 to 5.0, and of soluble carbohydrates from 12 to 46 cwt./acre. The top-dressing increased the protein content of all portions of the plant.The cob contributed, on a weight basis, 46% of the fresh crop, 49% of its dry matter, 54% of its crude protein and 54% of its soluble carbohydrates. Details are given of the chemical composition of the whole plant, and of its separate leaf, cob and stem, for each season and treatment.A later paper will deal with the making of silage from the maize crops and with the yield, composition and nutritive value of the silage.


Author(s):  
Carlos Augusto de Almeida Targino ALCOFORADO ◽  
Aianne Batista LIRA ◽  
Carla Giselly de SOUZA ◽  
Edson Mauro dos SANTOS ◽  
Safira Valença BISPO ◽  
...  

ABSTRACT Here in this study we assessed dairy heifers kept in tropical grasslands during spring and summer seasons to observe the effects of two supplementation strategies upon their performance. Sixteen dairy heifers (Holstein 5/8 x Gyr 3/4) with 135.25 kg of body mass were randomly assigned in two supplementation treatments (e.g., mineral salt and protein salt supplement) during spring and summer seasons, divided into two groups of eight animals that represented 4.29 animal unit ha. Initial and final fasted weights (i.e., feed and water withheld for 16h) were obtained before to start and at the end of each grazing cycle (28 days), and then the weight gain (kg animal-1) per grazing cycle was calculated by the difference between final and initial weights. There was no significant effect (P <0.05) on the intake of dry matter, crude protein, ether extract, neutral detergent fiber, and dry matter digestibility, between treatments (P <0.05). However, there was a significant effect (P <0.05) between seasons; e.g., respective means of dry matter intake (kg day-1,% BW g / kg 0.75), intake of crude protein (g day-1 g / kg 0.75), ether extract (g day-1), neutral detergent fiber (g day-1 and% BW) were 3.95 and 2.88 kg, 2.54 and 1.65%, 89.27 and 59.56 g kg0.75, 429.89 and 298.43 g day-1, 9.72 and 6.18 g kg0.75, 118.79 and 84.07 g day-1, 2.90 and 2.05 kg day-1, 1.86 and 1.18%, for Spring and Summer seasons. Moreover, the dry matter intake (% BW and g kg 0.75 of DM) were higher (P < 0.05) during the spring season (e.g., 2.53 vs 1.64 % BW; and 89.26 vs 59.56 g kg0.75 DM).


2018 ◽  
Vol 48 (5) ◽  
Author(s):  
Graciele Dalise Schirmann ◽  
Leonardo Tombesi da Rocha ◽  
Henrique da Costa Mendes Muniz ◽  
Josué Sebastiany Kunzler ◽  
Micheli Faccin Kuhn ◽  
...  

ABSTRACT: The aim of this study was to determine the chemical composition, digestibility, and net energy (NE) of broken rice (BRR), stabilized rice bran (SRB), and parboiled rice bran (PRB) for piglets. Two digestibility trials were performed with 12 and 18 male pigs with initial weights of 8 and 16kg, respectively. We performed total fecal collection using ferric oxide as fecal marker. The digestibility coefficients of organic matter, crude protein, and gross energy were higher (P<0.001) for the BRR compared to the SRB and PRB. The PRB presented a digestible energy 2% lower than that of BR and 5% higher than that of SRB. For BRR, average NE value was 3,228kcal/kg dry matter (DM), and the difference between the lower and higher value was 311kcal/kg DM. Average NE values of SRB and PRB were 2,896 and 3,293kcal/kgDM, respectively. The difference between the energy predicted by each equation reached 190kcal/kgDM for SRB and 285kcal/kgDM for PRB. In conclusion, BRR showed higher nutrient digestibility coefficients, except for EE and GE, which can be attributed to differences in the production processes. Regardless of the type of feedstuff tested, equations to predict NE values should be used carefully due to considerable differences in energy content.


1974 ◽  
Vol 54 (1) ◽  
pp. 55-64 ◽  
Author(s):  
H. T. KUNELIUS ◽  
L. B. MACLEOD ◽  
F. W. CALDER

Climax timothy (Phleum pratense L.), Saratoga bromegrass (Bromus inermis Leyss.), and Frode orchard grass (Dactylis glomerata L.) were harvested over a 3-yr period at eight developmental stages of primary growth and aftermath after a 40–64-day regrowth interval. Total dry matter (DM) yields generally increased up to flowering and ranged from 4,370 to 11,840 kg/ha, depending on grass species, cutting management, and season. Aftermath DM rarely exceeded 3,500 kg/ha. The stage of development at initial harvest had only a limited influence on aftermath production. Within the season, orchard grass had a more uniform yield distribution than timothy or bromegrass. The yield distribution of the three grasses was most uniform where the initial harvest was taken at the immature stages of development. Stand persistence was satisfactory under all cutting managements. Per cent in vitro digestible dry matter (IVD) of primary growth ranged from 76.5 to 37.0. In the 2nd and 3rd yr, decline in IVD of primary growth averaged 0.69, 0.66, and 0.82% per day for timothy, bromegrass, and orchard grass, respectively, over a 24-day period. In the 1st yr, this decline was somewhat higher. The IVD of aftermath tended to be higher when the regrowth period was shortest, although this was inconsistent, particularly for timothy and bromegrass. Total digestible DM yields increased up to heading stage. Percent crude protein (CP) of primary growth ranged from 18.2 to 7.1 under various cutting managements and decreased at an average daily rate of 0.33–0.37. Percent CP of aftermath ranged from 15.0 to 9.6. Longer regrowth periods generally resulted in lower percent CP. Cutting management had little effect on average seasonal CP yields.


1957 ◽  
Vol 48 (3) ◽  
pp. 305-314 ◽  
Author(s):  
M. E. Castle ◽  
A. S. Foot ◽  
Zena D. Hosking ◽  
S. J. Rowland

In 4 consecutive years, 1948 to 1952, combined varietal and manurial trials were carried out to obtain information on the yields of marrow-stem kale, thousand-head kale and cattle cabbage in the presence and absence of sulphate of ammonia applied as a top-dressing at the rate of 6 cwt./acre.Yield and composition of all crops were apparently affected by differences in weather conditions. In most years, and particularly for cabbage, the yield declined with successive harvests.Increased green crop, dry matter and crude protein yields resulted from the application of nitrogenous fertilizer in 3 years, but in the other year, a very dry season, the response to the top-dressing was negligible.Marrow-stem kale both with and without the additional fertilizer, yielded more, in terms of fresh crop, dry matter and crude protein, than thousandhead kale with the same manurial treatment. Cabbage yields often approached those of marrowstem kale at the first harvest, but were nearer to those of thousand-head by the last harvest of each year.


1983 ◽  
Vol 36 (1) ◽  
pp. 151-153 ◽  
Author(s):  
M. Ellis ◽  
M. Davies ◽  
P. A. Briggs ◽  
D. G. Armstrong

ABSTRACTA metabolism trial was carried out to examine the influence of an antibiotic food additive (Avoparcin) on the apparent digestibility of nutrients and nitrogen retention in the growing pig. Two groups of pigs, comprising 12 castrates per group, were fed a barley-based diet (190g crude protein per kg dry matter) with or without the inclusion of the antibiotic (at a dietary concentration of 20 mg/kg). Addition of Avoparcin had no significant effect on the apparent digestibility of dry matter or gross energy but resulted in a small increase in the apparent digestibility of nitrogen (0·012; P < 0·05). There was a corresponding improvement in nitrogen retention (0·051) but the difference was not statistically significant.


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