Nitrogen-fertilised grass in a subtropical dairy system 3. Effect of stocking rate on the response to nitrogen fertiliser

1995 ◽  
Vol 35 (2) ◽  
pp. 145 ◽  
Author(s):  
RT Cowan ◽  
KF Lowe ◽  
PC Upton ◽  
TM Bowdler

Two stocking rates, one as practised on farms (2 cows/ha) and the other 50% higher, were assessed for effect on pasture and milk yield response to applied nitrogen (N) fertiliser (0-600 kg N/ha. year) for Holstein-~Friesian cows grazing Rhodes grass (Chloris gayana) cv. Callide pastures. Pastures were grazed in combination with grazing oats for winter, with overall farm stocking rates of 1.17 and 1.37 cows/ha for ' the 2 treatments. Cows were maintained on these areas for 3 years. Cracked grain was given at 0.8 t/cow. year, and hay or silage supplements were given when green grass yield was <0.5 t dry matter (DM)/ha. The incremental response (P<0.05) in milk yield to each kg increase in level of applied N was 4.93 kg/ha at 1.17 cows/ha and 1.64 kg/ha at 1.37 cows/ha. The amount of conserved forage fed at the high stocking rate increased (530 and 970 kg/ha. year at 1.17 and 1.37 cows/ha), and financial margins over costs were reduced at the high stocking rate. The low milk response at the high stocking rate was associated with a low response in pasture growth. At <2 t pasture DM/ha on offer, incremental response to applied N declined, and there may have been an excessive loss of N through volatilisation in heavily grazed pastures. Milk yield per cow was closely related to total pasture yield on offer (P<0.01), and to leaf and stem yields (P<0.05). Relationships were stronger in summer and autumn than in spring. Over the full year, milk yield increased by 1.24 kg/kg leaf DM or 0.24 kg/kg total pasture DM on offer. At the higher stocking rate, surface soil (0-10 cm) concentrations of phosphorus and nitrate were higher than at the lower stocking rate. We conclude that in areas of moderate rainfall (<1000 mm/year) in the subtropics, high stocking rates resulting in low pasture yields and exposed ground surface will be associated with low efficiency of use of applied N.

1993 ◽  
Vol 33 (3) ◽  
pp. 283 ◽  
Author(s):  
WK Ehrlich ◽  
RT Cowan ◽  
A Reid

In a 2-part preliminary experiment, groups of 6 and 9 Holstein-Friesian cows in early t o mid lactation were unsupplemented or supplemented with either 3 kg cracked sorghum grain or 3 kg whole cotton seed on a base pasture of irrigated pangola grass for 12 weeks or oats for 12 weeks. The stocking rate was 5 cows/ha. Supplementation did not affect milk yield or composition. In a second experiment a group of 20 Holstein- Friesian cows in early to mid lactation grazed on a base pasture of subterranean clover at a stocking rate of 4 or 6 cows/ha a n d w e r e either unsupplemented or supplemented with 3 kg of whole cotton seed (WCS) over 12 weeks. Milk yield averaged 20.3 kg/cow.day and there were no significant effects on milk yield or composition. We suggest the lack of a significant milk yield response was due to a high substitution rate of WCS for pasture, associated with an oil content in the diet of 7.1 % of dry matter.


1983 ◽  
Vol 23 (123) ◽  
pp. 383 ◽  
Author(s):  
DL Lloyd ◽  
JG Nation ◽  
TB Hilder ◽  
PK O'Rourke

Three Makarikari grasses (Panicum coloratum var. makarikariense) viz. 0.4634, cv. Pollock and cv. Bambatsi and Rhodes grass (Chloris gayana) cv. Pioneer, each grown with lucerne (Medicago sativa) cv. Hunter River, and sward lucerne were compared for productivity and stability in a rotational grazing system at three stocking rates (22.2, 14.8 and 7 . 4 Merino wethers/ha for grasslucerne pastures; 14.8, 11.1 and 7.4/ha for lucerne swards) on a cracking clay soil on the Darling Downs, Queensland over four years. There were no differences between the Makarikari grass cvv. Pollock and Bambatsi pastures. However, each produced more dry matter and animal liveweight, and persisted better, than Rhodes grass pasture during dry conditions that occurred during the first two years. Rhodes grass nevertheless recovered during two subsequent wet summers. During those two dry years, wool production from sward lucerne was equal to that of the grass-lucerne pastures at both 14.8 and 7.4 animals/ha. Animal liveweight from lucerne was greater than from grass-lucerne pastures at 7.4 animals/ha only. Wide variation, both between and within seasons, was measured in the quantity of feed produced by pastures in this study. This is discussed in relation to the concept of stocking rate of pasture grown on limited areas of grain farms in the northern wheat belt, and to the provision of a continuing feed supply in integrated crop-pasture systems.


1969 ◽  
Vol 9 (36) ◽  
pp. 47 ◽  
Author(s):  
JE Coaldrake ◽  
CA Smith ◽  
JJ Yates ◽  
LA Edye

Liveweight gains of six yearling steers grazing on each of four introduced grasses, each with lucerne, were compared with those from native pasture and native pasture plus forage oats, on a weakly solonized brown clay loam of moderate fertility in the brigalow region of southern Queensland. The pastures were grazed continuously for three years (1963 to 1965) at set stocking rates during the worst drought known from 87 years of local records. At the height of the drought in 1965 the sown pastures supported animals as far into the drought as did the two native pasture treatments at half the stocking rate. Sorghum almum (CV. Crooble) and Rhodes grass (Chloris gayana CV. Pioneer) died late in the drought and did not re-establish after rain, whereas buffel grass (Cenchrus ciliaris CV. Nunbank) and green panic (Panicm maximum var. trichoglume CV. Petrie) survived. Standing dry matter in the pastures was less than 1,000 lb dry matter an acre for much of the life of the experiment. At a stocking rate of one bullock to 2.3 acres S. almm gave the highest average gain per head in the first full year of grazing (462 lb per head), but this was only significantly better (P<0.05) than the gain from buffel grass, and not significantly better than the gains (at one bullock to 4.6 acres) on native pasture (415 lb per head) and native pasture plus oats (390 lb per head). Rainfall in the first year was 18 inches. In the remaining two years, with 13 and 8 inches of rain respectively, there were no significant differences between the sown pastures until the S. almum and Rhodes grass died. Native pasture plus oats (681 lb per head) and native pasture (424 Ib per head) gave the greatest gain per head in 1964, but not per acre because of the lower stocking rate.


1982 ◽  
Vol 34 (2) ◽  
pp. 225-237 ◽  
Author(s):  
R. D. Baker ◽  
J. M. Barker ◽  
Y. L. P. Le Du

ABSTRACTForty-eight Hereford × Friesian cows and their South Devon calves were paddock grazed at high or low stocking rates of 412 or 206 cows and calves per ha in experiment 1, and either paddock grazed or set stocked at high or low stocking rates of 4·12 or 2·74 cows and calves per ha in experiments 2 to 4.There was no significant effect of grazing system on milk yield, milk composition or calf growth but in experiment 2 paddock-grazed cows gained more weight than those set stocked. Cows at low stocking rates gained more weight than those at high stocking rates and, in general, gave more milk. Calf growth rates were also higher at low stocking rates in experiments 1, 3 and 4 but not in experiment 2. Milk composition was not significantly affected by stocking rate. There were substantial increases in calf live-weight gain per ha at the high stocking rate but, because of a lower gain by cows, the differences in total live-weight gains per ha for cows and calves were much smaller.


2021 ◽  
Vol 33 (2) ◽  
pp. 239-244
Author(s):  
O. S. Onifade

A grazing trail was conducted to evaluate the effect of five stocking rates 12, 18, 24, 30 and 36 sheep/ha) on the chemical composition of Rhodes grass (Chloris gayana)- Stylo (Stylosanthes guinanensis) pastures in Nigeria. The pastures were set stocked for 154-210 days over five grazing periods. Stocking rate had no significant (P>0.05) effect on the crude protein (CP), phosphorus (P), potassium (K), calcium (Ca) and magnesium Mg) contents of the pasture components. The concentrations of CP, K and Ca declined as plants matured while the levels of CP, P and Ca in the stewm were short of the recommended levela for rams. Acid detergent lignin (ADL) and fibre (ADF) were not affected by stocking rate but the neutral detergent fibre (NDF) of the components increased with stocking rate. The non-persistence of Style beyond one grazing period lowered the chemical composition of the pasture thus the need to incorporate more persistent legume(s) with the grass.


1978 ◽  
Vol 18 (90) ◽  
pp. 12 ◽  
Author(s):  
RT Cowan ◽  
TM Davison

Twenty-four Friesian cows grazing green panic (Panicum maximum var. trichoglume)-glycine (Glycine wightii cv. Tinaroo) pastures at 2 or 4 cows ha-1 were fed no supplement, 2.4 kg maize or 3.0 kg molasses cow-1 day-1. The experiment was a randomized block design and of six months duration. Milk yield and composition were similar for cows fed maize and molasses and these supplements increased average milk yield from 10.3 to 11.8 kg cow-1 day-1 (P < 0.05). Increased stocking rate reduced milk yield from 12.7 to 9.8 kg cow-1 (P < 0.01). Interactions of stocking rate with type of supplement were not significant (P > 0.05). The level of supplement intake and yield of pasture on offer accounted for 52 per cent of the variation in average milk yields (P < 0.01). Of the variation in milk yields between paddocks only 5 per cent was unaccounted for by this relationship.


2018 ◽  
Vol 15 (4) ◽  
pp. e0608
Author(s):  
Ana I. Roca-Fernández ◽  
Antonio González-Rodríguez

The aim was to evaluate the prediction accuracy of pasture dry matter intake (PDMI) and milk yield (MY) predicted by the GrazeIn model using a database representing 124 PDMI measurements at paddock level and 2232 MY measurements at cow level. External validation of the model was conducted using data collected from a trial carried out with Holstein-Friesian cows (n=72) while grazed 28 paddocks and were managed in a 2×2 factorial design by considering two calving dates (CD), with different number of days in milk (DIM), early (E, 29 DIM) vs. middle (M, 167 DIM), and two stocking rates (SR), medium (M, 3.9 cows ha-1) vs. high (H, 4.8 cows ha-1), under a rotational grazing system. Cows were randomly assigned to four grazing scenarios (EM, EH, MM and MH). The mean observed PDMI of the total database was 14.2 kg DM cow-1 day-1 while GrazeIn predicted a mean PDMI for the database of 13.8 kg DM cow-1 day-1. The mean bias was −0.4 kg DM cow-1 day-1. GrazeIn predicted PDMI for the total database with a relative prediction error (RPE) of 10.0% at paddock level. The mean observed MY of the database was 23.2 kg cow-1 day-1 while GrazeIn predicted a MY for the database of 23.1 kg cow-1 day-1. The mean bias was –0.1 kg cow-1 day-1. GrazeIn predicted MY for the total database with a mean RPE of 17.3% at cow level. For the scenarios investigated, GrazeIn predicted PDMI and MY with a low level of error which made it a suitable tool for decision support systems.


1998 ◽  
Vol 1998 ◽  
pp. 108-108
Author(s):  
J. A. Fregonesi ◽  
J.D. Leaver

Space allowance could be an important variable affecting production, health, reproductive performance and behaviour of dairy cattle. Also, high and low yielding cows may have different ways of coping with insufficient space allowance. The aim of this experiment was to study the influence of space allowance and milk yield level on the performance and behaviour of strawyard housed dairy cows.The experiment was carried out using 24 Holstein Friesian cows with two groups in early lactation of high (over 30 kg/day milk yield) and two groups in late lactation of low yield (under 25 kg/day milk yield). The groups were allocated to strawyard systems with low stocking density (bed area/cow = 9 m2; pen area/cow = 13.5 m2; feed face width/cow = 1.5 m) or high stocking density (bed area/cow = 4.5 m2; pen area/cow = 6.75 m2; feed face width/cow = 0.75m) conforming to a changeover design with two periods, each of four weeks. The cows were fed a total mixed ration ad libitum and 2kg/cow/day of concentrate in the milking parlour. All animals were milked twice daily.


animal ◽  
2016 ◽  
Vol 10 (5) ◽  
pp. 796-804 ◽  
Author(s):  
D. Lawrence ◽  
M. O’Donovan ◽  
T.M. Boland ◽  
E. Lewis ◽  
E. Kennedy

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Magdalena Kolenda ◽  
Dariusz Piwczyński ◽  
Marcin Brzozowski ◽  
Beata Sitkowska ◽  
Piotr Wójcik

AbstractThe aim of the present study was to evaluate the changes in selected production and functional traits of Polish Holstein-Friesian cows after switching from a conventional (CMS) to an automatic milking system (AMS). The study consisted of 3398 Polish Holstein- Friesian dairy cows, from 16 herds in which CMS was changed to AMS. Cows were in their 1st (L1) or 2nd lactation (L2). The data consisted of milk yield [MY, kg], fat content [FC, %], protein content [PC, %], dry matter [DM, %], lactose content [LC, %], urea content [MU, mg/l], somatic cell count [SCC, thous./ml] and score [SCS, log]. The milking system had a significant impact on milk yield, fat, lactose, dry matter and urea contents. Regardless of lactation number, milk derived from CMS was characterised by higher values for FC, PC, DM SCC and SCS, while milk from AMS had higher MY, LC and MU. Multifactor analysis of variance also confirmed significant effect of herd, season, herd × milking system interaction on SCS in milk of cows in L1. In the studied herds change from CMS to AMS was evaluated separately for cows in L1 and L2. The transitioning from CMS to AMS resulted in the decrease of fat content in 6 L1 and 7 L2 herds, dry matter in 8 L1 and 5 L2 herds. SCS in milk also decreased in 4 L1 and 5 L2 herds. The change caused the increase of MY in 11 L1 and 9 L2 herds, lactose content in 6 L1 and 4 L2 herds and urea content in 9 L1 and 10 L2 herds. AMS may positively affect milk yield and health status, however, the change of milking system should be also accompanied by the change in herd management.


Sign in / Sign up

Export Citation Format

Share Document