scholarly journals Economic effects of nutritional constraints early in life of cattle

2009 ◽  
Vol 49 (6) ◽  
pp. 479 ◽  
Author(s):  
A. R. Alford ◽  
L. M. Cafe ◽  
P. L. Greenwood ◽  
G. R. Griffith

An experiment was conducted at the Grafton Agricultural Research Station on the northern coast of New South Wales whereby low and high pasture nutritional systems were imposed on a herd of Hereford cows during pregnancy and from birth to weaning in a factorial design. Offspring representing extremes of growth to birth and/or weaning were then selected for study of long-term consequences of growth early in life. Implications of the nutritional treatments of cows on subsequent weaning rates were also tested with data from previous studies. The extent to which these extreme maternal nutritional and offspring growth scenarios affected herd profitability was tested with the Beef-N-Omics decision support package. For the representative cattle enterprise modelled, gross margin per hectare ranged from $A114 to $A132. In all cases, the gross margin for those groups with fetal growth based on a higher level of nutrition exceeded that of their peers on a lower level of nutrition. It is more profitable for cows and calves to have access to a high standard of nutrition during pregnancy and up to weaning than for them to have access only to a poor standard of nutrition. Incorporating differential weaning rates following maternal nutritional treatments reduced gross margins per hectare by up to 30%. On average, a 1% reduction in weaning rate resulted in a 4.5% reduction in gross margin. Restricted cow–calf nutrition affects the future cow fertility, as well as the current calf progeny, economically.


2014 ◽  
Vol 54 (10) ◽  
pp. 1625 ◽  
Author(s):  
S. R. McGrath ◽  
J. M. Virgona ◽  
M. A. Friend

Slow pasture growth rates during winter limit the potential gross margins from autumn and early winter lambing in southern New South Wales (NSW) by limiting stocking rates and/or increasing supplementary feed requirements. Dual-purpose crops can reduce the winter feed gap in mixed-farming systems by increasing the available feed in winter. The simulation software AusFarm was used to model a mixed-farming system at Wagga Wagga with Merino ewes joined to terminal sires and grazing lucerne-subterranean clover pasture over a 41-year period. A paddock of dual-purpose wheat was then added to the system, and ewes were allowed to graze the wheat crop when feed on offer reached 850 kg DM/ha and before GS31. Weaned lambs were sold after late August if lamb growth rates fell below 20 g/head.day, mean lamb weight reached 45 kg or production feeding of lambs was required. Lambing in June resulted in the highest median gross margin whether or not ewes were able to graze the wheat crop during winter. Grazing of a dual-purpose wheat crop resulted in greater proportional increases in gross margins as stocking rate was increased, increased lamb production and reduced supplementary feeding costs, and reduced interannual variability in gross margin returns.



1969 ◽  
Vol 9 (37) ◽  
pp. 151 ◽  
Author(s):  
JR Giles ◽  
JP Drinan

The seasonal variation in fertility and fecundity of Bungaree and Peppin Merinos was compared at the Agricultural Research Station, Trangie, New South Wales. Ewes of both strains were joined to rams of both strains for 32 days on nine occasions ; each joining being separated from adjacent periods by an interval of 10 days. For six weeks after joining the ewes were run with vasectomized rams and were then slaughtered over the following six weeks. Incidence of oestrus and ovulation rate of the two strains were similar at all times. More Bungaree than Peppin ewes returned to service, particularly during the autumn, irrespective of the strain of rams to which they were joined. There was no difference between ram strains in percentage of ewes returning to service or percentage of ewes pregnant, but a significantly higher proportion of ova were lost in pregnant ewes with multiple ovulations after joining to Bungaree rams in winter and spring.



1969 ◽  
Vol 9 (37) ◽  
pp. 147 ◽  
Author(s):  
BJ McGuirk

Single character selection flocks-Folds Plus (selection for high fold score) and Folds Minus (selection for low fold score) were established in 1951 from a Peppin Merino flock at Trangie Agricultural Research Station, New South Wales. For the period 1951 to 1966, 25 per cent of rams selected for the Folds Plus flock were rejected following semen examination before joining, compared to only three per cent of Folds Minus rams (P<0.05). The fertility of individual rams in the two flocks has been estimated from the lambing performance of the ewes to which they were mated in the period 1951 to 1963. Averaged over the twelve joinings, a higher proportion of ewes mated to Folds Minus rams lambed following both artificial insemination (53 v. 45 per cent) and paddock joinings (57 v. 47 per cent). The lower fertility of the Folds Plus rams was not due to a higher proportion of completely infertile rams.



2009 ◽  
Vol 49 (6) ◽  
pp. 535 ◽  
Author(s):  
B. L. Davies ◽  
A. R. Alford ◽  
G. R. Griffith

The ‘Regional Combinations’ project and its biophysical outcomes have been described in several other papers in this special edition. The information provided in these papers allows an evaluation of the most profitable beef cattle production systems across different environments in southern Australia. In this paper, the focus is on the New South Wales experimental site where the trial animals were finished in a feedlot. The data identified liveweight gain as the biggest driver of profitability of production. Between growth treatments, there was a large difference in the gross margins before feedlot entry between the ‘fast’ and ‘slow’ treatments favouring the fast-grown animals, even after accounting for the higher cost of producing pasture capable of sustaining faster growth. However, the slow growth treatments consistently outperformed the fast growth treatments in the feedlot. In terms of breeds, the European breed types consistently outperformed the Wagyu breeds. There were no time-of-calving experiments in New South Wales.



1973 ◽  
Vol 13 (64) ◽  
pp. 510 ◽  
Author(s):  
H Brownlee

Two grazing experiments were performed between 1965 and 1969 at the Agricultural Research Station, Condobolin, to determine the carrying capacity of Jemalong barrel medic (Medicago truncatula) pasture. In each experiment the pasture was set stocked with Merino wethers at 3.1, 4.1 and 6.2 ha-1. An additional treatment stocked at 6.2 ha-1 was included in which two-thirds of the pasture area was saved during autumn or periods of feed shortage while stock were confined to the other one-third. In both experiments the pasture supported 3.1 wethers ha-1 under set stocking for three years with little supplementary feeding and regenerated successfully each year. No major changes in botanical composition were recorded, and Jemalong medic remained the major component of the pasture. Autumn saving at 6.2 ha-1 mitigated the effects of the high stocking rate on both animal and pasture, but did not result in worthwhile animal production increases.



1976 ◽  
Vol 16 (79) ◽  
pp. 197 ◽  
Author(s):  
OR Southwood ◽  
DG Saville ◽  
AR Gilmour

In an experiment at the Agricultural Research Station, Temora, New South Wales, Merino breeding ewes with their lambs grazed continuously from 1966 to 1970 at three stocking rates, 5, 7.5 and 10 ewes ha-1, on annual Trifolium subterraneum clover pasture topdressed every autumn with superphosphate fertilizer at nil, 94 or 188 kg ha-1. Stocking rate had an effect on ewe body weight in autumn each year and in winter and spring of the last year but it had no effect no wool production per ewe. Apart from the dry year, stocking rate had no effect on lamb performance. Superphosphate had little effect on ewe body weight and none on wool production but there were more lambs on the fertilized treatments than on the unfertilized pastures in 1967 when rainfall was low. Fertilizer encouraged barley grass dominance whereas the pasture not topdressed grew more clover and produced more burr. With no topdressing, available soil phosphate declined steadily over the five years to less than half the initial level. The results indicate that in a spring lambing, Merino ewe enterprise in the southern New South Wales wheat belt, where clover-ley farming is the general practice, annual pasture topdressing is no longer necessary after approximately 1000 kg ha-1 superphosphate has been applied to the soil and the fertilizer is continued through the cropping phase.



1966 ◽  
Vol 6 (21) ◽  
pp. 121 ◽  
Author(s):  
DG Fowler ◽  
RB Dun

Three experiments were done to establish whether differences in ram fertility could explain some of the differences in reproductive performance observed between two flocks of Merino sheep, one flock of which had been bred for a high (Folds Plus) and the other for a low (Folds Minus) degree of skin wrinkle at the Trangie Agricultural Research Station. In the first experiment the quality of semen collected from Folds Plus and Folds Minus rams at Glenfield, New South Wales, was examined during the period December 1962 until March 1963. From late January until early March 1963, Folds Plus rams had low quality semen which gave a conception rate of 38.6 per cent. Over the same period, Folds Minus rams had higher quality semen which gave a conception rate of 58.6 per cent. Folds Plus and Folds Minus rams were then subjected to a severe heat treatment in mid winter 1963 (experiment 2) which produced severe seminal degeneration in both Folds Plus and Folds Minus rams. Folds Plus rams were more susceptible to heat than Folds Minus rams since the semen of Folds Plus rams remained degenerate for a longer period than the semen of Folds Minus rams and, in a test mating program, fewer pregnancies were observed in ewes artificially inseminated with the semen of Folds Plus rams than in ewes inseminated with the semen of Folds Minus rams. In a third experiment Folds Plus and Folds Minus rams from two independently established selection experiments at Trangie and at Cunnamulla were subjected to a heat treatment. The heated Folds Plus rams from both selection experiments exhibited marked seminal degeneration, but heated Folds Minus rams from both selection experiments maintained high quality semen throughout the experiment. The heated Folds Plus rams from Cunnamulla were more severely affected than the heated Folds Plus rams from Trangie.



1975 ◽  
Vol 15 (77) ◽  
pp. 747 ◽  
Author(s):  
OR Southwood ◽  
GE Robards

From 1967 to 1971 a grazing experiment was conducted at the Agricultural Research Station, Temora, New South Wales with Merino ewes and first cross spring lambs on lucerne pastures. Set stocking was compared with a number of rotational systems at twice replicated stocking rates of five and ten ewes ha-1. The rotational systems consisted of either five or seven paddocks each grazed to give a constant pasture recovery time of 36 days year round, or 36 days mid-summer to mid-winter and 24 days when lambs were present. Stocking rate was the only variable affecting ewe wool production and body weight. During the driest year the constant rotation was the best treatment, whereas in the wetter year ewes managed in a variable rotation grew most wool. The number of lambs born and their birth weight did not vary among treatments. Growth rate was slower at the higher stocking rate but the management treatments had no effect on lamb growth. Lucerne plant density decreased by half during the first three years of the experiment. Thereafter plant density was maintained in the rotationally grazed systems. Under continuous grazing at the high stocking rate no lucerne survived after four months but at the low stocking rate most remaining plants died after a spring drought in 1971.



1978 ◽  
Vol 18 (95) ◽  
pp. 745 ◽  
Author(s):  
BJ McGuirk ◽  
ME Bourke

An experiment was conducted at Cowra Agricultural Research Station, New South Wales, to determine the importance of hybrid vigour to the productivity of crosses between Border Leicester and Merino sheep. In five years, 1963 to 1967, Border Leicester (BL) and Merino (M) rams were paddock-joined to a mixed flock of ewes of both breeds for five weeks in March-April. The results of these purebred and crossbred matings have been compared. Cummulative weekly raddle counts were similar for both purebred mating groups (BL x BL and M x M) and by the end of joining over 95 per cent of ewes in both groups had been raddled. When the mating data for the Border Leicester ewes were examined, Merino rams raddled fewer ewes than did Border Leicester rams. This breed difference between rams was significant for the number of ewes raddled by the end of both the first and second week of joining (P < 0.05) and the difference in favour of the Border Leicester rams was still apparent at the end of joining (97 vs. 86 per cent, not significant). The reproductive performance of the Merino ewes (M x M) was superior to that of the- Border Leicesters (BL x BL), with 1.05 vs. 0.93 lambs born per ewe joined. The Border Leicester flock had higher incidences of both dry ewes (63.7 vs. 79.3 per cent ewes lambing of those joined) and multiple births (1.47 vs. 1.33 lambs born per lambing ewe). Because of the difference in the mating activity of the two Border Leicester ewe flocks (M x BL vs. BL x BL), the most reliable estimates of the relative performance of purebred and crossbred matings were given by the number of lambs born per lambing ewe, and the number of ewes lambing to first service. The crossbred matings were superior for both characteristics, by 4.6 and 5.7 per cent respectively, but neither difference was statistically significant.



1986 ◽  
Vol 8 (2) ◽  
pp. 140 ◽  
Author(s):  
BH Downing

Examination of data on dietary preferences of sheep, goats and cattle suggests that different grazing systems are desirable for each of the three major woodland types (belah-rosewood, mulga, poplar box) examined. Competition for herbs, frequently palatable to all animal species, indicates that goats and sheep are unsuitable for joint use either in heavily wooded country or where annual herbaceous production is less than 200 kg-ha. Supplementary feeding, fire and judicious stocking are proposed as a strategy for inducing goats to eat a proportion of unpalatable shrubs. The literature provides little helpful information on how rangelands in the Western Division should be managed. No reports are given on comparisons of grazing systems, such as rotational grazing, rotational resting, and continuous grazing. No guidance is given on grazing after burning of the rangeland. Recommendations are generally against the use of goats for control of woody plants, whereas local observation shows this to be an apparently effective practice. The recommendations are mostly based on experimental procedures which, although suitable for detecting animal dietary preferences in the short term, are less appropriate for investigation of the effects of grazing on range condition in the long term. Some suggestions are made towards a different approach for: investigating the effects of grazing by sheep and goats on rangeland condition, and the economic implications of this in terms of animal production.



Sign in / Sign up

Export Citation Format

Share Document