Greater Forage Production Research Articles

Effect of introduction of Kazungula grass (Setaria sphacelata), spacing and nitrogen on the productivity of a natural grassland

An experiment was conducted during 1995 and 1996 under rainfed condition, to study the effect methods of introduction of Kazungula grass [Setaria sphacelata Schum (L.) Stapf Hubbard ex Moss], spacing and N levels produc tivity of natural grasslands of Assam Agricultural University, Jorhat. Introduction of Setaria either by killing or without killing the existing vegetation at different spacings could not influence the production of herbage and crude protein during both the years. However, no killed plots produced higher dry matter and crude proteins than killed plots. Closer spacings of 30 cm x 30 cm and 40 cm x 40 cm recorded 5.18 and 4.79% higher green forage and 20.75 and 14.23% dry matter yield, respectively, over the wider spacing of 50 cm x 50 cm. On an average, increasing the N levels up to 120 kglha increased the green forage, dry matter . and crude protein yields as well as enriched the soil with organic carbon,. available N, P and K. The optimum economic dose of N was 145.66 kg Nlha in respect of green forage production.

<b>Subject Review Article</b>: Broiler litter as feed for ruminants - Potential and limitations under Nigerian Conditions

In Nigeria, ruminant livestock are often underfed mostly during the dry season of the year due to high environmental temperature, poor green forage production and high cost of feed. This has resulted in the inclusion of alternative feedstuffs in animal rations. Broiler litter plays a vital role in supplying and correcting nutrient deficiencies in animal nutrition. Generally, growth rate, milk production and feed efficiency were higher in animals (sheep, goats and cattle) fed broiler litter-based diet than in animals fed control diet (without broiler litter). This paper reviews the nutritional value, health hazard, processing techniques and factors affecting the acceptability of broiler litter as feed. (Ghana Journal of Agricultural Science, 1997, 30(1): 79-85)

Comparing fall and spring seeding of Kochia scoparia on saline soil

Kochia scoparia naturally invades distributed soils in the Brown soil zone of the Canadian Prairies and offers potential as a forage crop in saline environments. A 3-yr study conducted on severely saline soil near Swift Current, Saskatchewan, compared kochia production resulting from fall (natural- and implement-seeded) and spring (early- and late-seeded) treatments. Late spring-seeded crops produced, on average, 5.4 t of dry, shoot biomass per ha per yr. Early spring and fall-seeded kochia (naturally or implement-placed) yielded between 5.4 and 10.9 t ha−1. Of the nine comparisons between forage yields from fall and spring seedings, six favored fall over spring, two were equal, and one produced more forage from early spring seedings than from the naturally-seeded fall treatment. The late spring treatment consistently produced the least forage. Fall seedings exhibited a greater potential for forage production because fall-seeded plants usually established early in the growing season and in sufficient number to fully exploit soil and water resources when conditions became favorable and effective rooting depths were not restricted by concentrated salt layers. When drier growing conditions prevailed, the lower plant densities associated with early spring seedings tended to minimize plant competition and foster greater forage production. Key words: Kochia forage, seeding dates, salinity, Kochia establishment, Kochia agronomy

Response of irrigated fodder oats to nitrogen fertilization as influenced by tillage

Irrigated green forage production under reduced tillage is thwarted by the failure to obtain adequate N fertilization. Forage accumulation, yield and nitrogen response in relation to tillage and N application were studied for two years during 1980–1982. Forage accumulation, plant height and final forage yield were significantly affected under minimum tillage (T 1). However, plant growth and green and dry forage yields were comparable under reduced (T 2) and conventional (T 3) tillage. Reduction in yield under T 1 was associated with restricted root growth and high soil strength and bulk density in the surface and subsurface layers. The optimum dose of N for T 1, T 2 and T 3 was calculated to be 107, 120 and 113 kg N ha −1 and the estimated dry matter yield for these rates of N under each of the three tillage systems was 6.6, 9.1 and 9.5 t ha −1, respectively. The interaction between different tillage systems and N application rates for green and dry matter production was not significant.

Seasonal variations in the herbage mass, crude protein and in-vitro digestibility of native perennial grasses on the north-west slopes of New South Wales.

Seasonal variations in herbage mass, crude protein content and in-vitro organic matter digestibility of both the warm-season (summer-growing) native perennial grasses, Aristida mrnosa R.Br., Bothriochloa macra (Steud) S.T. Blake, Dichanthium sericeum R.Br. (Camus), Sporobolus elongatus RBI., Chloris truncata R.Br. and Eragrostis leptostachya Steud, and the year-long-green perennial grasses Stipa variabilis Hughes and Danthonia linkii Kunth were investigated at three sites on the North-West Slopes of New South Wales. These preliminary data were used to assess the relative grazing value of the dominant grasses in the region, although these initial rankings can only be confirmed by diet selection and animal production studies. The eight grasses tested were classified into three groups with respect to their green leaf mass per unit basal area throughout the year: (i) Aristida ramosa, Bothriochloa macra, Dichanthium sericeum and Sporobolus elongatus had low amounts of green leaf in winter and their green leaf mass in summer was related to rainfall. (ii) Chloris truncata and Eragrostis leptostachya showed considerably less seasonal variation in the amount of green leaf and had a higher percentage of green leaf than (i). (iii) Stipa variabilis and Danthonia linkii had the lowest variation in green leaf, and in winter and spring they generally had higher green leaf masses than the other groups. Among the warm-season and year-long-green grasses the green leaf crude protein content varied between 5 and 15% throughout summer and autumn and from 6 to 17% in winter and spring. In all seasons dead leaf crude protein contents were around 5% and dead stem crude protein contents were consistently less than 6%. Irrespective of species the digestibilities of the green leaf portions were higher in spring and summer (60 to 80%) than in autumn and winter (50 to 60%). At each of the ~ites the digestibility ofDanthonia linkii green leaf material was generally higher than 60% in all seasons, but that ofStipa variabilis green leaf was always less than 60%. Estimates of green stem digestibility ranged from as low as 25% for Avistida ramosa in autumn to around 60% for most other species in spring. Digestibilities of dead leaf ranged from 30 to 55%, those of dead stem ranged from 20 to 40%. These results indicate that Danthonia linkii is potentially valuable for grazing and that Aristida ramosa is an undesirable pasture species. Of the other grasses tested Chloris truncata and Eragrostis leptostachya may produce some green forage in autumn and winter but at these times the green forage production of Aristida ramosa, Bothriochloa macra, Dichanthium sericeum and Sporobolus elon- gatus is limited by low temperatures.

Influence of seed size and composition on the dry matter yield ofCenchrus ciliaris

Higher food reserve in larger seeds ofCenchrus ciliaris contributed towards greater forage production, as compared to that of the small seeds, only during the 1st year of establishment.

Grazing management of native pastures in the New England region of New South Wales. I. Pasture and sheep production with special reference to systems of grazing and internal parasites

In a 4-year grazing experiment with Merino sheep, on a native pasture dominated by Bothriochloa ambigua S.T. Blake, three rates of stocking and continuous v. rotational grazing were compared. The effects of these treatments on the forage available and the botanical composition of the pasture and on sheep liveweights, size of sheep, wool production, wool fibre diameter, and parasitic infestation, both with and without drenching with phenothiazine, mere studied. The effects of seasonal conditions on the above and on the chemical composition of the pasture were also recorded. No consistently significant differences between grazing treatments in their effects on the pasture or on sheep liveweights or parasitic infestation were recorded, although during the final 3 years the total forage available was less under heavy stocking. Seasonal variations in total forage mere not marked, but, production of green forage increased greatly in the spring and declined to a very low level during winter. Similarly, sheep liveweights increased during spring and summer and declined in the winter. These liveweight changes were significantly correlated with the amount of green forage available. Wool fibre diameter showed similar seasonal fluctuations but the maximum diameter was attained earlier than maximum liveweight. Coincident with a spring rise in the amount of green forage there was also an increase in the percentages of crude protein and phosphorus in the green components of the pasture. Liveweight gains of the drenched sheep were significantly greater from the beginning of each experimental year in the late spring (November) to late winter (August) in all stocking treatments. In the spring, when the quality of the pasture improved and worm egg counts were low, drenching had no effect on liveweight gains in three out of four years. Drenching also significantly improved wool production and resulted in an increase in skeletal size of sheep in three out of four years. Drenching reduced egg counts of the parasites Oesophagostomum spp. and Haemonchus contortus (Rudolphi) Cobb but was less effective against Trichostrongylus-Ostertagia spp. For all grazing treatments there was no significant difference in the amount of wool produced per head, but over the 4-year period 56 per cent. more wool per acre was produced from the heavy than from the light rate of stocking.

Autecology of some natural pasture species at Trangie, N.S.W.

Features of the autecology of four native perennial grasses (Stipa, Chloris, and Digitaria spp.) and an important group of winter annual species are reported from a 5-yr study of a naturaI pasture at Trangie, N.S.W. The investigation was mainly concerned with the response of the species to changes in seasonal climatic conditions. The study period (1948–52) was relatively moist (mean annual rainfall 25.6 in.) and the growing season (May–November) longer than average. Available moisture showed considerable variation in autumn and spring, and was the primary factor in the variable success of germination and seedling survival among the perennial grasses. Plant development in the perennial grasses is discussed for three study intervals, March 1948–50 (above average rainfall), March 1950–51 (recurrent flooding over 8 months), and March 1951–52 (including a long, dry summer) ; in all pkriods striking fluctuations were noted in persistency and basal area of established plants, particularly the small plants of each species. Available moisture is advanced as the principal factor controlling seasonal distribution of green forage production by the perennial grasses, temperature becoming limiting only at midwinter (June–July). All species conformed to a similar production pattern, showing a midsummer minimum (except in January 1951), late summer and spring peaks, and a midwinter trough. Flowering and maturation periods are listed for the perennial grasses, and infrequent but heavy seed production recorded for all species. Characteristic features of the root systems are discussed in relation to drought resistance and response to effective rainfall. Germination of Medicago spp. was most frequent in May and June (1-in. soil temperature 51–61°F), but was also successful in March, April, and July. Erodium cygnorum and Hordezcm leporinum favoured late February to early May (65–75°F) for germination. Among high populations percentage seedling survival was low, even in a very favourable season. Given adequate winter moisture (as in 1948 and 1949), Medicago spp. and E. cygnorum showed virtually an exponential increase in green forage production between May and September. The level of September production of these species is shown to be correlated with moisture availability in April. The principal factors ensuring regular recurrence of the winter annuals in pastures of the Trangie environment are outlined and discussed.

A survey of the natural pastures of the Trangie District, New South Wales, with particular reference to the grazing factor.

The Trangie district has a rainfall of 1,750 points with a slight summer maximum, a high relative variability of rainfall, and high summer temperatures. Disclimax pasture communities produced by a range of sheep grazing intensities operative during the past 20-30 years are described. On light soils ungrazed pasture comprises a wide range of perennial grasses. Light grazing (1 sheep per 2 acres) gives increased dominance by Stipa fulcata. With successive increases in grazing pressure Chloris acicdaris and Stipa setacea become conspicuous in turn, only to be virtually replaced by Chloris trumata as grazing intensity reaches 1 sheep per 0.5 acre. On heavy soils Stipa aristiglumis is dominant under light grazing. With increased rate of stocking, first Sporobolus caroli and then Stipa setacea gain dominance. At the highest stocking rates all these species are largely replaced by Chloris truncata. Throughout the sere the number of species is far more restricted than on the light soils. The striking feature of these results is that though botanical composition of the perennial grass component on light and heavy soils respectively is vastly different under light grazing, it becomes similar under heavy grazing and almost identical under severe grazing. Degenerative changes common to pastures of both soil groups under increasing grazing pressure are the decline in density and basal area of the perennial grass component, the greater population of winter and summer annuals, and the declining contribution of perennial grasses to green forage production in the spring. The basis of these findings is firstly the measurement of basal area, density and yield of perennial grasses, and density and yield of annual species in pastures of varying stocking history, and secondly, the measurement of pasture composition in relation to increasing distance from watering points.

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