Browsing by Autor "D. P. Poppi"

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Effect of the concentration of Spirulina (Spirulina platensis) algae in the drinking water on water intake by cattle and the proportion of algae bypassing the rumen
(CSIRO Publishing, 2010) Tanda Panjaitan; S. P. Quigley; S. R. McLennan; D. P. Poppi
Spirulina, a freshwater microalgae, has previously been shown to increase the efficiency of microbial protein production in cattle fed hay with a low crude protein content. The present study was carried out to determine the effect of increasing the concentration of Spirulina in the drinking water on the intake of water and the amount of water containing Spirulina bypassing the rumen of cattle. Five rumen-cannulated steers were given a fixed amount of pangola grass hay (14 g DM/kg W.day–1) and water containing 0, 1, 2, 2.7 and 3.5% (w/w) Spirulina in an incomplete Latin square design. Water intake by the control steers (0% Spirulina) was 29.7 and 49.3 g/kg W for the first drinking event after it was made available and over 24 h, respectively. For steers receiving the algae, intake of water plus Spirulina increased linearly (P &lt; 0.01) from 42.7 to 60.2 g/kg W during the first drinking event, as the concentration of Spirulina in the drinking water increased, but over 24 h was not affected by Spirulina concentration and averaged 74.4 g/kg W. The bypass of water through the rumen, as determined using chromium-EDTA as a marker, averaged 20.5 ± 1.2% and was not affected by the concentration of Spirulina in the drinking water. Increasing inclusion of Spirulina was associated with a decrease in rumen pH, an increase in urea concentration in blood serum, and an increase in ammonia-N concentration, propionate and branched-chain fatty acids, and a decrease in butyrate proportions in rumen fluid. Spirulina inclusion in the drinking water increased water intake and may provide a potential safe and inexpensive alternative to urea for extensively grazed ruminants.
Nutritional research to meet future challenges
(CSIRO Publishing, 2010) D. P. Poppi; S. R. McLennan
Nutrition is a mature science with well established principles for energy, protein and mineral metabolism based on known metabolic pathways. The quantitative requirements are summarised within various international feeding standards and models. However, when these are applied to specific circumstances, especially in northern Australia, the response of the animal to nutrient supply does not always agree with that predicted from the feeding standards or the error of prediction is not sufficiently accurate for practical use. There is a need for the continual testing of these relationships within production systems. Molecular methods have the potential to discover new metabolic relationships within tissues and characterise the microbial ecology and its relationship to rumen function. Suitable problem models based on growth, meat quality, reproduction, milk and fibre production, and environmental consequences need to be identified. We suggest that production systems designed to meet market weight for age specifications, growth paths and compensatory growth, skeletal growth, parasites, fatty acid isomers, adaptation to low crude protein diets, rumen microbial ecology, epigenetics, remote data acquisition and animal management, greenhouse gas emission, and C balance of various production systems are important problem models, the research of which will benefit the future of the livestock industries in Australia.
Predicting feed intake and liveweight gain of Ongole (Bos indicus) cattle in Indonesia
(CSIRO Publishing, 2014) Dianne Mayberry; Theo Mahiseta Syahniar; Risa Antari; G. P. Ningrum; Marsetyo Marsetyo; Dicky Pamungkas; D. P. Poppi
We evaluated the precision and accuracy of equations from the Australian Ruminant Feeding Standards (ARFS) and the Large Ruminant Nutrition System (LRNS) in predicting the performance of Ongole (Bos indicus) cattle under Indonesian conditions. A database was constructed using information from 121 cattle in five different pen-feeding experiments. Cattle included mature cows and growing bulls, and they were fed a range of diets commonly used by Indonesian farmers. We compared observed and predicted dry matter intake and daily liveweight gain. Model predictions were evaluated for precision and accuracy using mean bias, mean square prediction error and regression of observed against predicted values. Across all experiments, the LRNS provided the better estimates of intake and growth. While both models included animal age, sex, weight and body condition score, the LRNS provided better estimates of metabolisable energy requirements for maintenance of liveweight, feed quality and efficiency of energy utilisation. The LRNS model also better accounted for environmental conditions by including correction factors for minimum night temperature and relative humidity, in addition to average daily temperatures. Based on our results, the LRNS model appears suitable for use in Indonesian beef-production systems.
Rice straw, cassava by-products and tree legumes provide enough energy and nitrogen for liveweight maintenance of Brahman (Bos indicus) cows in Indonesia
(CSIRO Publishing, 2014) Risa Antari; G. P. Ningrum; Dianne Mayberry; Marsetyo Marsetyo; Dicky Pamungkas; S. P. Quigley; D. P. Poppi
The aim of this experiment was to test the effectiveness of two diets in increasing liveweight (LW) and body condition score (BCS) of Brahman cows in Indonesia. Diets were based on rice straw, with additional energy and nitrogen (N) provided in the form of onggok (a cassava by-product) plus urea or a tree legume. Thirty mature, non-pregnant, non-lactating Brahman crossbred cows (288 kg LW, BCS 2/5) were allocated to one of two treatment groups. Cows were kept in individual pens for 21 weeks and offered one of two diets; (1) urea-supplemented rice straw ad libitum plus 10 g onggok DM/kg LW.day, or (2) untreated rice straw ad libitum plus 5 g onggok DM/kg LW.day and 5 g Gliricidia sepium DM/kg LW.day. The urea supplement provided no advantages over using locally available N sources such as gliricidia, with both supplement types meeting the rumen-degradable N requirements of the cows. Cows on both diets gained weight at a similar rate (0.19 kg/day) for the first 15 weeks of the experiment. Liveweight gain in Weeks 16–21 was only 0.04 kg/day, despite an increase in total feed intake and energy content of the diets compared with Weeks 1–15. Liveweight of cows stabilised during Weeks 16–21 at 304 kg, BCS 2.2. While our results demonstrate that Brahman cows can maintain LW on rice straw-based diets, they may not be able to maintain a BCS sufficient for good reproduction rates (i.e. BCS 3 or higher on 1–5 scale). Better quality diets containing higher levels of energy are required for cows to gain and maintain a suitable BCS.
Spirulina (Spirulina platensis) algae supplementation increases microbial protein production and feed intake and decreases retention time of digesta in the rumen of cattle
(CSIRO Publishing, 2014) Tanda Panjaitan; S. P. Quigley; S. R. McLennan; A. J. Swain; D. P. Poppi
Cattle consuming pastures low in protein have low liveweight gain due to low rumen degradable protein (RDP) supply and thus low microbial crude protein (MCP) production and efficiency of MCP production [EMCP, g MCP/kg digestible organic matter (DOM)]. Nitrogen supplements can increase MCP production and EMCP of cattle grazing low protein pastures. The objective of this study was to compare the effects of supplementation with a non-protein-N source (NPN), in this case urea and ammonium sulfate (US), with a single-cell algal protein source (Spirulina platensis), on intake, microbial protein supply and digestibility in cattle. Nine cannulated Bos indicus steers [initial liveweight 250.1 ± 10.86 (s.d.) kg] were fed Mitchell grass hay (Astrebla spp; 6.1 g N, 746 g NDF/kg DM) ad libitum and were supplied with increasing amounts of US (0, 6, 13, 19 and 33 g US DM/kg hay DM) or Spirulina 0, 0.5, 1.4, 2.5 and 6.1 g Spirulina DM/kg W.day in an incomplete Latin square design. The response of MCP production and EMCP to increasing amounts of the two supplements was different, with a greater response to Spirulina evident. The MCP production was predicted to peak at 140 and 568 g MCP/day (0.64 and 2.02 g MCP/kg W.day) for the US and Spirulina supplements, respectively. The highest measured EMCP were 92 and 166 g MCP/kg DOM for the US and Spirulina treatments at 170 and 290 g RDP/kg DOM, respectively, or a Spirulina intake of 5.7 g DM/kg W.day. Increasing RDP intake from US and Spirulina resulted in an increase in Mitchell grass hay intake and rumen NH3-N concentration and reduced the retention time of liquid and particulate markers and digesta DM, NDF and lignin in the rumen with greater changes due to Spirulina. Total DM intake peaked at a Spirulina supplement level of 4.6 g Spirulina DM/kg W.day with a 2.3-fold higher DOM intake than Control steers. Rumen NH3-N concentrations reached 128 and 264 mg NH3-N/L for the US and Spirulina treatments with a significant increase in the concentration of branched-chain fatty acids for the Spirulina treatment. The minimum retention time of liquid (Cr-EDTA; 23 and 13 h) and particulate (Yb; 34 and 22 h) markers in the rumen were significantly lower for Spirulina compared with US and lower than unsupplemented animals at 24 and 34 h for Cr-EDTA and Yb, respectively. Spirulina could be provided safely at much higher N intakes than NPN supplements. The results suggest that, at an equivalent RDP supply, Spirulina provided greater increases than US in MCP production, EMCP and feed intake of Bos indicus cattle consuming low protein forage and could also be fed safely at higher levels of N intake.
The effect of sucrose addition on intake of a tropical grass hay by sheep
(CSIRO Publishing, 2012) A. de Vega; D. P. Poppi
Increasing levels of sucrose (15, 30, 45, and 60% of the total dry matter intake, DMI) were added to a Control diet of a tropical grass hay (pangola grass, Digitaria eriantha) to examine the effect on DMI and digestible organic matter intake (DOMI). A pelleted lucerne (Medicago sativa) diet provided a positive Control diet with a higher metabolisable energy intake. There were positive linear and quadratic effects of sucrose addition on DMI and DOMI, reflecting increasing values from Control to 45% sucrose, which then decreased for 60% sucrose. Intake values at 45% sucrose were equivalent to 49% (DMI) and 60% (DOMI) of those shown by animals fed on pelleted lucerne. At the same time there was a decrease in hay intake and neutral detergent fibre digestibility. Rumen concentration of butyric acid increased with sucrose addition. Eating pattern changed with increasing sucrose inclusion in that meals extended over the whole day rather than most food being consumed within 5 h as occurred with the high roughage diet. Intake of sucrose was similar for all diets by 5 h, but by 24 h high sucrose diets had resulted in a higher intake of sucrose. It was suggested that the underlying characteristics of the neutral detergent fibre present in the diet regulate intake by posing a limit, which cannot be overridden.
The level of tree legumes required to meet the maintenance energy requirements of Ongole (Bos indicus) cows fed rice straw in Indonesia
(CSIRO Publishing, 2012) Theo Mahiseta Syahniar; Risa Antari; Dicky Pamungkas; Marsetyo Marsetyo; Dianne Mayberry; D. P. Poppi
Improving the productivity and profitability of smallholder cattle enterprises in Indonesia requires greater and more efficient utilisation of underutilised feed resources such as rice straw. The experiment tested the hypothesis that an Ongole cow with low energy requirements can maintain weight (W) on a rice straw-based diet with the addition of a small amount of tree legumes. Thirty-two Ongole cross (Bos indicus) cows were allocated to one of four treatments in a randomised block design with eight cows per treatment. Cows were offered untreated rice straw ad libitum with four levels of tree legumes (0, 11, 21, and 42 g DM/kg W0.75.day) for 20 weeks. Feed intake was determined daily and liveweight was measured every second week. There was no difference in total feed intake between the treatment groups (P &gt; 0.05). Intake of tree legumes was higher when more was offered (P &lt; 0.05), but cows did not consume all of the legumes offered to them. The inclusion of tree legumes in the diet had no effect on organic matter digestibility, ME content of the diet, liveweight gain or estimated energy balance of the cows (P &gt; 0.05). Rice straw alone contained insufficient ME and rumen-degradable N to meet the maintenance requirements of the cows. From the regression relating liveweight change and ME intake for all cows across all diets, the inclusion of tree legumes in the diet at ~12 g DM/kg W0.75.day or 2.8 g DM/kg W.day was enough to meet the energy requirements for maintenance of Ongole cows fed rice straw ad libitum.
The liveweight gain response of heifers to supplements of molasses or maize while grazing irrigated Leucaena leucocephala/Digitaria eriantha pastures in north-west Australia
(CSIRO Publishing, 2012) S. R. Petty; D. P. Poppi
This experiment in the Ord River Irrigation area (ORIA) of north Western Australia evaluated the liveweight gain of cattle rotationally grazing leucaena (Leucaena leucocephala cv. Cunningham)/pangola (Digitaria eriantha cv. Steudel) pastures alone, or supplemented with four levels of molasses (1.25, 2.50, 3.75, 5.00 kg molasses/head.day, as fed or fresh weight basis) or two levels of cracked maize supplementation (0.75, 1.50 kg/head.day, as fed or fresh weight basis). Seventy Bos indicus cross heifers [~12 months of age, mean initial weight 252 ± 3.8 (s.e.) kg] were allocated to the seven treatments and two replicates of each treatment (five cattle per replicate plus five additional similar heifers) with the stocking rate set at 6.25 head/ha. The experiment was conducted over 106 days of the dry season (August–November). Each replicate paddock of 0.4 ha was rotationally grazed with 10 animals with a 7-day grazing period and a 21-day regrowth period for each rotation. The mean herbage mass, residual herbage mass and herbage allowance for the experiment were 3.78 t DM/ha, 3.07 t DM/ha and 7.32 kg DM/100 kg liveweight, respectively. Pangola contributed a mean of 0.79 of the herbage mass. There was a significant quadratic response of liveweight gain to level of molasses supplement (P &lt; 0.0087) with an optimum liveweight gain of 1.08 kg/head.day at a supplement level of 2.65 kg molasses/head.day or 8.9 g/kg LW.day derived from the quadratic equation. The quadratic equation was: Liveweight gain = 0.763(±0.0644) + 0.241(±0.0658) * M – 0.046(±0.0126) * M2 (where M is level of molasses supplement kg/head.day). There was no significant response to level of maize supplement. There were no significant differences between treatments in the concentration of rumen ammonia N or volatile fatty acids or in the molar proportion of volatile fatty acids. It was concluded that molasses can be used effectively to increase the liveweight gain of cattle grazing leucaena/pangola pasture at a level of ~8.9 g/kg LW.day.