Evaluation of feed additives for increasing wool production from Merino sheep. 2. Flavomycin and tetronasin included in lucerne-based pellets or wheaten chaff fed ad libitum

1989 ◽  
Vol 29 (3) ◽  
pp. 327 ◽  
Author(s):  
EM Aitchison ◽  
K Tanaka ◽  
JB Rowe
Keyword(s):  
Feed Intake ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Fibre Diameter ◽  
Feed Additives ◽  
Protein Diet ◽  
Merino Sheep ◽  
Wool Growth ◽  
Ad Libitum ◽  
Pelleted Diet

The feed additives flavomycin, a glycolipid antibiotic, and tetronasin, an ionophore, were evaluated for their ability to improve wool growth and liveweight gains in Merino sheep. Each was included in 2 diets: one was a pelleted mixture of (g/kg) lucerne (590), lupins (250) and barley (1 50); the other diet was wheaten chaff. Flavomycin was included in each diet at 10 and 20 mg/kg feed; tetronasin at 5 and 10 mg/kg feed. During an 8-week experimental period, the diets were fed ad libitum to weaner Merino wethers, with 15 sheep receiving each treatment diet at each level of additive inclusion, and 30 sheep receiving each diet without additives. Liveweight changes, feed intake and wool growth were measured over 2 consecutive 4-week periods, and rumen fluid samples were taken from all sheep after 6 weeks. Feed intake, liveweight gain and wool growth rate were all higher for animals eating the pelleted diets compared with those eating chaff. Rumen volatile fatty acids (VFA) and ammonia (NH3) concentrations were also higher with the pelleted diet. On the pelleted diet, flavomycin and tetronasin inclusion significantly increased liveweight gains during the second 4-week period (296, 277, 231 g/sheep.day for flavomycin, tetronasin and controls respectively, P<0.001), but neither additive had any significant effect on feed intake. The amount of clean wool grown during both measurement periods was greater for animals receiving flavomycin or tetronasin with the pelleted diet compared with control animals. Neither additive had any significant effect on liveweight gains or wool growth of sheep eating chaff. Fibre diameter (FD) was measured on wool clipped in the second period, and was not significantly altered by either additive: mean FDs for animal receiving pellets were 25.1 �m, compared with 18.5 �m for animals receiving chaff. Total rumen VFA concentrations were lower with flavomycin or tetronasin treatments on both diets, and ammonia concentrations were lower with both additives on the pelleted diet and with tetronasin on the chaff diet. It is concluded that both flavomycin and tetronasin were able to increase liveweight gains and wool growth in rapidly growing sheep eating a high-protein diet, but had little or no consistent effects with animals eating a lower quality, low-protein diet.

Liveweight gain and wool growth in sheep fed rations containing virginiamycin

1992 ◽  
Vol 32 (8) ◽  
pp. 1037 ◽  
Author(s):  
PJ Murray ◽  
JB Rowe ◽  
EM Aitchison ◽  
SG Winslow
Keyword(s):  
Feed Intake ◽  
Fibre Diameter ◽  
Barley Grain ◽  
Feed Additive ◽  
Feed Conversion ◽  
Merino Sheep ◽  
Growing Period ◽  
Wool Growth ◽  
Ad Libitum ◽  
Pelleted Diet

The feed additive virginiamycin was evaluated for its potential to improve wool growth and liveweight gain in Merino sheep in 2 experiments. In the first experiment 84 wethers (about 10 months old) were housed individually and fed ad libitum a pelleted diet based on lucerne chaff, lupin, and barley grain. Control sheep (28) were fed an unmedicated diet, and 14 in each of 4 groups were given diets containing 10, 20, 40, or 60 mg virginiamycin/kg pellets. Virginiamycin was found to reduce feed intake during the first 4-5 weeks of the experiment when included at levels 220 g/t. There was a dose-related reduction in liveweight gain. There was no significant effect of virginiamycin on wool growth. In the second experiment, weaners and adults from 2 locations in Western Australia, Mount Barker (relatively high rainfall) and Wongan Hills (relatively low rainfall and shorter pasture-growing period), were housed individually in a shed and fed a pelleted diet at rates equivalent to 3.5 and 3.1%, respectively, of liveweight for weaners and adults. The pelleted ration was based on wheat and lucerne chaff, lupin grain, and fishmeal. Virginiamycin was included at 20 mg/kg pellets for 16 of 40 sheep of each age and location. The remaining sheep were fed the unmedicated diet. Feed conversion and liveweight gain improved (P<0.05) in response to the inclusion of virginiamycin during the first 4 weeks of the trial, but wool growth was reduced over the same period. Virginiamycin had no effect on fibre diameter in sheep in either experiment.

Evaluation of feed additives for increasing wool production from Merino sheep. 1. Lasalocid, avoparcin and flavomycin included in lucerne-based pellets or oaten chaff fed at maintenance

1989 ◽  
Vol 29 (3) ◽  
pp. 321 ◽  
Author(s):  
EM Aitchison ◽  
IG Ralph ◽  
JB Rowe
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Ammonia Concentration ◽  
Rumen Fermentation ◽  
Feed Additives ◽  
Control Groups ◽  
Merino Sheep ◽  
Wool Production ◽  
Wool Growth ◽  
Pelleted Diet

Three feed additives were studied for their potential to improve wool growth in sheep fed 2 diets; oaten chaff, or a pelleted mixture (g/kg) of lucerne (590), lupins (250), barley (1 50) and a mineral and vitamin mix (10). Additives were included with each diet as follows (mg/kg feed): avoparcin 25,50,75; flavomycin 5, 15, 30; lasalocid 30, 50, 70. Diets were fed at maintenance to mature Merino wethers for 9 weeks, and measurements were made of wool growth and rumen fermentation characteristics. Animals fed the pelleted diet grew more wool than those fed the chaff diet (6.3 compared with 5.1 g/m2.day, P<0.001), but none of the additives resulted in any significant differences in wool growth compared with the controls. The additives avoparcin and lasalocid increased the ratio of the volatile fatty acids propionate:acetate in animals eating both of the diets (P< 0.001), but flavomycin had no significant effect. Rumen ammonia concentration was increased with avoparcin on both diets (P< 0.001) and with lasalocid and flavomycin on the pelleted diet ( P < 0.05). None of the additives tested significantly influenced liveweight change in comparison with the control groups.

PRELIMINARY EVALUATION OF THE ADDITION OF GLUCOGENIC MATERIALS TO THE RATIONS OF LACTATING COWS

1971 ◽  
Vol 51 (3) ◽  
pp. 721-727 ◽  
Author(s):  
L. J. FISHER ◽  
J. D. ERFLE ◽  
F. D. SAUER
Keyword(s):  
Fatty Acids ◽  
Propylene Glycol ◽  
Milk Fat ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Preliminary Evaluation ◽  
Early Lactation ◽  
Lactating Cows ◽  
Ad Libitum ◽  
Beta Hydroxybutyrate

Glutamate, succinate, propylene glycol, or glycerol were added to a basic concentrate at 3.3% of air-dry feed. Each concentrate was fed both ad libitum and in restricted amounts to four cows in early lactation. Dietary intake, milk yield and composition, molar proportions of rumen volatile fatty acids and blood glucose, ketones and plasma free fatty acids were used as criteria of effect of these supplements. Propylene glycol in the diet resulted in a lower intake of concentrate compared with glycerol (11.44 versus 14.30 kg/day) and significantly decreased (P < 0.05) rumen butyrate and plasma beta-hydroxybutyrate. Glutamate supplementation prevented the fall in milk fat content which occurred when the other three supplemented concentrates were fed ad libitum, and this effect may have been related to the constancy in the ratio of acetate to propionate in the rumen fluid.

The intake, digestibility and utilization of a low-quality roughage by Brahman cross, buffalo, banteng and Shorthorn steers

1979 ◽  
Vol 30 (2) ◽  
pp. 333 ◽  
Author(s):  
JB Moran ◽  
BW Norton ◽  
JV Nolan
Keyword(s):  
Feed Intake ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Lower Proportion ◽  
Energy Utilization ◽  
Residence Times ◽  
Fluid Flow Rate ◽  
Faecal Excretion ◽  
Voluntary Feed Intake ◽  
Nitrogen Phosphorus

The intake, digestibility and utilization of a low quality (0.8% nitrogen) sorghum hay was studied in Brahman cross, buffalo, banteng and Shorthorn steers. Comparisons of diet utilization were made after data were adjusted for differences in liveweight and feed intake. There were no significant differences (P < 0.05) between species in voluntary feed intake, faecal excretion of organic matter, cellulose and energy, and urinary excretion of nitrogen, phosphorus and energy. Utilization of water was least efficient in the buffaloes and most efficient in the banteng. The concentrations of ammonia and volatile fatty acids in the rumens of Brahman crosses, buffaloes and bantengs were similar, but the Brahman crosses had a higher proportion of butyric and a lower proportion of propionic acid than the other two species. The bantengs had a smaller rumen fluid volume and a slower rumen fluid flow rate but all three species had similar mean marker residence times in the rumen. The results from this experiment support the view that there are few differences between cattle species in their ability to digest and utilize a low quality roughage when comparisons are made between animals of similar liveweight and feed intake.

Effect of condensed tannins on the production of wool and on its processing characteristics in sheep grazing Lotus corniculatus

1998 ◽  
Vol 49 (4) ◽  
pp. 597 ◽  
Author(s):  
B. R. Min ◽  
W. C. McNabb ◽  
P. D. Kemp ◽  
T. N. Barry
Keyword(s):  
Blood Plasma ◽  
Feed Intake ◽  
Condensed Tannins ◽  
Rumen Fluid ◽  
Fibre Diameter ◽  
Lotus Corniculatus ◽  
Plasma Metabolites ◽  
Plasma Urea ◽  
Wool Production ◽  
Wool Processing

The effect of condensed tannins (CT) in Lotus corniculatus upon voluntary feed intake (VFI), concentration of rumen and plasma metabolites, production of wool, and wool processing characteristics was measured in grazing ewes restricted to maintenance feeding for 125 days during summer. A rotational grazing system with restricted feed allowance with 40 mixed aged dry ewes (54±1·0 kg) was used. Half of the ewes were selected randomly for twice-daily oral polyethylene glycol (PEG; MW 3500) supplementation (CT-inactivated), with the remainder being CT-acting animals. Measurements of the diet selected, VFI, wool production, and wool processing characteristics were made. The concentration of ammonia in rumen fluid and the concentrations of methionine, cysteine, and urea in blood plasma were also measured. The diet selected contained 32 g total nitrogen (N) and 28 g total CT/kg dry matter (DM) and had an in vitro organic matter digestibility of 0·70. Action of CT reduced rumen ammonia concentration (256 v. 302 mg N/L), reduced blood plasma urea concentration (7·3 v. 8·9 µM), and increased blood plasma cysteine concentration (30 v. 27 µM) compared with sheep receiving PEG supplementation. CT had no effect on VFI but increased clean fleece weight (2·53 v. 2·28 kg/ewe) and staple length (7·7 v. 6·9 cm), but did not affect liveweight gain (54 v 67 g/day). The CT reduced dag weight and tended to reduce wool yellowness relative to sheep receiving PEG. There were no signifiant effects of CT on fibre diameter, staple strength, bulk density, and wool resilience. It was concluded that action of CT in sheep fed L. corniculatus reduced the degradation of forage protein in the rumen and the principal effect of this was to increase the efficiency of wool production, with more wool being produced at the same feed intake and the wool being of reduced yellowness.

Fibre diameter and staple strength of sheep selected for divergent clean fleece weight when subjected to an increase in intake or an increase in intake and diet change

2005 ◽  
Vol 56 (2) ◽  
pp. 195 ◽  
Author(s):  
M. A. Friend ◽  
G. E. Robards
Keyword(s):  
Growth Rate ◽  
Stepwise Regression ◽  
Fibre Diameter ◽  
Dietary Treatment ◽  
Diet Change ◽  
Wool Growth ◽  
Ad Libitum ◽  
Staple Strength ◽  
Fleece Weight ◽  
Ad Libitum Feeding

Merino wethers with a high (fleece plus, Fl+) or low (fleece minus, Fl–) potential for wool growth were offered a restricted intake of either oat grain or lucerne chaff for 8 weeks followed by ad libitum lucerne chaff for 4 weeks. The Fl– sheep that were fed oats then lucerne had a lower (P < 0.05) intake during the first 2 weeks of ad libitum feeding than all other groups. Staple strength of Fl+ sheep (37.5 ± 2.2 N/ktex) was less (P < 0.05) than that of Fl– sheep (44.5 ± 2.4 N/ktex), and dietary treatment did not significantly affect staple strength. Wool growth rate was unaffected by dietary treatment, but was greater (P < 0.001) for Fl+ (6.4 ± 0.2 µg/mm2.day) than for Fl– (4.0 ± 0.2 µg/mm2.day) sheep. Along-fibre variation in diameter was greater (P < 0.001) in Fl+ (15.6 ± 0.5%) than in Fl– (9.9 ± 0.5%) sheep. Between-fibre variation in diameter was greater (P < 0.001) in Fl+ (16.5 ± 0.5%) than in Fl– (13.2 ± 0.5%) sheep, and between-fibre variation in diameter was affected (P < 0.05) by dietary treatment in Fl+ sheep. Staple strength was significantly correlated (P < 0.05) with along-fibre variation in diameter (r = –0.48), and stepwise regression analysis indicated that along-fibre variation in diameter, wool growth rate during early restricted feeding, and minimum fibre diameter explained 63% of the variance in staple strength. The results are discussed in relation to the lower staple strength of Fl+ sheep.

The influence of protein quality on the effect of flavomycin on wool growth, liveweight change and rumen fermentation in sheep

1990 ◽  
Vol 41 (5) ◽  
pp. 987 ◽  
Author(s):  
PJ Murray ◽  
JB Rowe ◽  
EM Aitchison
Keyword(s):  
Protein Quality ◽  
Rumen Fluid ◽  
Initial Period ◽  
Fibre Diameter ◽  
Experimental Period ◽  
Feed Additive ◽  
Wool Production ◽  
Wool Growth ◽  
The Mean ◽  
Wheat Chaff

The feed additive flavomycin, a glycolipid antibiotic, was evaluated for its potential to improve wool growth in sheep fed two pelleted diets: one based on lucerne chaff and lupin grain and the other on wheat chaff and fishmeal. Seventy-eight weaner ewes, approximately 20 months of age and mean weight of 32 kg (s.e. � 0.3), were placed in individual pens and fed the pelleted diets at a level equivalent to 3.5% of the mean liveweight of the group. The experiment consisted of an initial period (8 weeks) during which all animals received their respective diets with no flavomycin, followed by an experimental period (9 weeks) during which the animals received their diets with flavomycin. Flavomycin was included at three different rates (l0, 20 and 40 ppm) in both diets (nine sheep/level) during the experimental period and twelve sheep were fed each of the unmedicated diets (no flavomycin). Feed intakes were measured daily and animals weighed weekly. Wool growth was measured for the initial and experimental periods by clipping a mid-side patch of about 100 cm2. In sheep fed the lucernellupin based diet, flavomycin increased liveweight gain ( P < 0.05) at 20 ppm but had no effect on wool production, whereas in those fed the hay/fishmeal diet, there was a linear decrease in liveweight gain (P < 0.001) (161, 151, 142, 130 g day-1) and a dose related increase in clean wool production (P<0.01) (12.9, 14.5, 15.2, 15.3 g m-2 day-1) with increasing rates of flavomycin (0, 10, 20, 40 ppm respectively). There was no significant effect of flavomycin on fibre diameter in the sheep fed either diet. The inclusion of flavomycin in both diets significantly increased the molar proportions of propionate in the rumen fluid and in sheep on the hay/fishmeal pellet it reduced the concentration of rumen ammonia. The time animals took to eat their ration was increased with the inclusion of flavomycin in the hay/fishmeal diet.

The use of thyroxine to reduce average fibre diameter in fleece wool when feed intake is increased

2001 ◽  
Vol 41 (5) ◽  
pp. 611 ◽  
Author(s):  
G. J. Lee ◽  
K. J. Thornberry ◽  
A. J. Williams
Keyword(s):  
Saline Solution ◽  
Daily Intake ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Treatment Groups ◽  
Average Fibre Diameter ◽  
Wool Growth ◽  
Average Fibre ◽  
Ad Libitum ◽  
The Difference

An experiment was conducted to determine whether thyroxine injections would control the increases in fibre diameter when the wool growth of Merino wethers is stimulated by an increased supply of feed. Fifty-seven sheep were allocated to 1 of 5 levels of daily intake, ranging from 0.75 maintenance to ad libitum, and injected every third day with 3 mg of L-thyroxine or a saline solution (control). Sheep treated with thyroxine had elevated plasma tri-iodothyronine (T3) levels, which were highest in sheep fed the least (P<0.01). Ad libitum intakes of sheep treated with thyroxine tended to be higher than that of control sheep, particularly in the fifth to seventh weeks of the experiment, and liveweight gain over the initial 4 weeks was significantly (P<0.001) less. Wool growth was increased by thyroxine treatment, although the difference was small in the second half of the experiment at the highest intake levels. Fibre diameter of sheep treated with thyroxine was greater at low intakes, although the difference diminished as intake increased. Fibre length in the second half of the experiment was positively related to intake, but there were no effects of thyroxine. Although the relationships of fibre diameter and length with wool growth did not differ between the treatment groups, length accounted for more of the variation in wool growth in the second half of the experiment in treated wethers than in control wethers (0.376 v. 0.182 of the variation, respectively). Thyroxine did not appreciably reduce the extent of the increase in fibre diameter associated with an increase in the availability and intake of feed.

Nutrient metabolism and rumen micro-organisms in sheep fed a poor-quality tropical grass hay supplemented with sulphate

1990 ◽  
Vol 115 (2) ◽  
pp. 269-275 ◽  
Author(s):  
M. Morrison ◽  
R. M. Murray ◽  
A. N. Boniface
Keyword(s):  
Feed Intake ◽  
Rumen Fluid ◽  
Poor Quality ◽  
Nutrient Metabolism ◽  
Heteropogon Contortus ◽  
Molar Proportion ◽  
Group A ◽  
Ad Libitum ◽  
The Difference ◽  
Group B

SUMMARYA feeding trial was performed during 1986, in Townsville, Australia, to describe alterations in nutrient metabolism, and the coincident gross changes in rumen microbiology, when a sulphurdeficient diet was supplemented with inorganic sulphur. Eight Merino sheep were fedad libituma spear grass (Heteropogon contortus) hay of low sulphur content (0·4 g/kg DM), supplemented with all other essential minerals. Upon supplementation, daily sulphur intake was increased toc.0·75 g and four animals continued to be fedad libitum(group A) whilst the remaining animals were restricted in feed intake (group B). Sulphur supplementation caused a twofold increase in the feed intake of group A (P< 0·05). In both groups of animals, sulphur supplementation increased the fermentation of cotton thread cellulose (P< 0·05), as well as of ground plant dry matter (P< 0·05), suspended in the rumen in nylon bags for 24 and 48 h. The apparent digestibility of organic matter (AOMD) was also increased by sulphur supplementation; from 30·6 to 39·3% in group A (P< 0·05) and from 35·1 to 41·5% in group B (P> 0·05). The difference in AOMD between groups with sulphur supplementation was not significant, despite group B maintaining a longer retention of fluid digesta in the rumen (20·7 v. 25·3 h) with a significantly lowered rumen volume (4·68 v 3·67 litres,P< 0·05) and outflow of fluid digesta from this site (5·31 v 3·58 litres/day,P< 0·05). Sulphur supplementation increased the molar proportion of acetic acid in rumen fluid (P< 0·05) but lowered propionic and butyric acids in group A (P< 0·05). Only the molar proportion of propionic acid in rumen fluid was significantly lowered in group B (P< 0·05). In both groups of animals, counts of fluid-borne rumen bacteria, protozoa and sporangia of rumen anaerobic fungi (RAF) all increased significantly with sulphur supplementation (P< 0·05 in all instances), but no significant differences were observed between groups in microbial counts, despite the different feeding regimes. The increase in sporangial forms of RAF was most marked; no sporangial forms were detectable until the diet was supplemented with sulphate and measurable concentrations of rumen sulphide were observed. This is the first account of nondetectable concentrations of RAF brought about by the nutritional status of the diet.

Effects of level of intake and urea supplementation of alkali-treated straw on protozoal and bacterial nitrogen synthesis in the rumen and partition of digestion in cattle

1988 ◽  
Vol 39 (6) ◽  
pp. 1181 ◽  
Author(s):  
BS Punia ◽  
J Leibholz ◽  
GJ Faichney
Keyword(s):  
Fatty Acids ◽  
Feed Intake ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Water Volume ◽  
Medium Size ◽  
Total Volatile ◽  
High Feed ◽  
High Level ◽  
Microbial N

Six Friesian heifers (c. 300 kg) fitted with cannulas were given diets of wheat straw sprayed with NaOH (4.4 % wlw) and essential minerals either with or without urea (3% w/w). The total protozoal numbers in the rumen fluid were not significantly different between dietary trcatments (mean 6.2 X 104/ml). However, there were more holotrichs and medium-size entodiniomorph protozoa in the rumen fluid of the cattle given the HU and LU diets than the Hand L diets. Protozoal counts in the omasal fluid were 44% of those in rumen fluid. The apparent digestibilities of OM and neutral-detergent fibre (NDF) in the stomach and in the total tract were lower with high than low feed intakes. The urea supplement enhanced the digestibilities of OM and NDF in the stomach and in the total tract. The total nitrogen (N) and non-ammonia N (NAN) flowing to the omasum and to the duodenum per unit of N intake were significantly greater with the low than the high feed intakes and with urea supplementation of the diets than without urea supplementation. The proportions of total microbial N and bacterial N in omasal NAN were higher with the supplement of urea than the unsupplemented straw. The bacterial N in the NAN flowing to the omasum was lower for the high than the low intakes. Concentrations of ammonia-N and total volatile fatty acids in rumen fluid were higher for the ureasupplemented straw than the unsupplemented straw. The high level of feed intake was associated with higher water volume and solid contents in the rumen.

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