The effect of Haemonchus contortus infection on haematological parameters in young Merino sheep and its significance for productivity

1990 ◽  
Vol 50 (1) ◽  
pp. 99-109 ◽  
Author(s):  
G. A. A. Albers ◽  
G. D. Gray ◽  
L. F. Le Jambre ◽  
I. A. Barger ◽  
J. S. F. Barker
Keyword(s):  
Weight Gain ◽  
Haemonchus Contortus ◽  
Serum Iron ◽  
Live Weight ◽  
Haematological Parameters ◽  
Live Weight Gain ◽  
Wool Growth ◽  
Faecal Egg Count ◽  
Faecal Egg Counts ◽  
Iron Concentrations

ABSTRACTFaecal egg counts, haematocrits, erythrocyte potassium contents and serum iron concentrations were determined in 1005, 3- to 5-month-old Merino lambs infected with a single dose of 11 000 Haemonchus contortus larvae. Live-weight gain and wool growth also were recorded. Lambs were infected in six different groups over a 3-year period. When infections were terminated after 5 weeks, faecal egg counts in the six infected groups had reached a peak of 5170 to 20 339 eggs per g (average 12 909), haematocrits had declined to between 196 and 309 ml/1 (average 233), erythrocyte potassium contents had risen to between 16·7 and 37·5 mequiv. per 1 (average 31·5) and serum iron concentrations, in some cases following an erratic course, had dropped to between 0·512 and 1·546 mg/1 (average 0·946).Of the three haematological parameters, haematocrit correlated best with faecal egg count (r = 0·7 in four of six infected groups). However, in two groups with low faecal egg counts this correlation was much lower (r = 0·3). Erythrocyte potassium concentration and serum iron concentration significantly correlated with variability of haematocrit not accounted for by faecal egg count, suggesting that both erythropoiesis and iron availability influence the degree of anaemia.The effect of H. contortus infection on productivity of lambs was best predicted by haematocrits: for each further 0·01 proportional decrease in haematocrit, a 0·03 reduction of live-weight gain over a 9-week post-infection period, a 0·007 reduction in clean wool growth and a 0·004 reduction in fibre diameter over a 4- to 9-week period were observed. Some evidence was obtained indicating a tolerance level of anaemia at approximately 280 ml/1 packed cell volume.

scholarly journals Nitrogen balance studies with the milk-fed lamb

1967 ◽  
Vol 21 (2) ◽  
pp. 237-256 ◽  
Author(s):  
D. M. Walker ◽  
L. J. Cook
Keyword(s):  
Weight Gain ◽  
Protein Content ◽  
Dry Matter ◽  
Live Weight ◽  
N Balance ◽  
Live Weight Gain ◽  
Wool Growth ◽  
Period 2 ◽  
The Mean ◽  
Dietary Treatments

1. Sixteen male cross-bred lambs were given four diets, which differed in the ratio of protein to energy. The protein contents of the diets (on a dry-matter basis) were: 6.1% (diet A), 11.9% (diet B), 17.5% (diet C) and 22.9% (diet D).2. The experimental period of 7 weeks was divided into two 2-week periods (periods 1 and 2), and one 3-week period. The diets given to the lambs were changed between period 1 and period 2. In period 3 all the lambs were given the same dietary treatment as in period 2.3. The daily feed intake of the lambs was regulated according to live weight. Adjustments were made at the beginning of period 1 and of period 2. The level of feeding was 121 kcal/kg live weight 24 h. In period 3 the intake was the same as in period 2.4. Diet digestibility, live-weight gain, and nitrogen and sulphur balances were calculated for each lamb on each diet in all the periods. Wool growth on sample areas was measured over a 2-week and a 4-week period. These wool growth periods corresponded to treatment period 1, and treatment periods 2 and 3, respectively. At the end of the experiment the lambs were slaughtered and the composition of carcass and organs was determined.5. The mean digestibilities of energy, N, ether extractives and dry matter increased significantly as the protein content of the diet increased.6. The live-weight gain increased with increasing protein content of the diets, but only the difference between the means for diet A and all other diets was significant.7. The N and S balances increased with increasing intake of apparently digested N and S, and all differences between the means for individual diets were highly significant.8. There was a significant correlation between N balance and live-weight gain for each diet. However, when compared at the same late of gain, N balance increased as the protein content or the diet increased.9. Wool growth on the sample areas increased with an increase in the protein content of the diet and all differences between the means for individual diets were highly significant. There were no significant differences between the dietary treatments in their effect on the N and S contents of the wool. The mean values were 15.7% N and 2.87% S.10. The retention of N in the wool grown did not account for the increased N retention on the diets of higher protein content. The lambs given diet A, retained more N and S in wool than was supplied by the diet.11. The percentage of fat in the carcass decreased, and the percentage of protein increased as the protein content of the diet increased. The percentages of moisture and ash were not significantly affected by the dietary treatments.12. The percentages of moisture in the liver, pancreas and muscle decreased and the percentages of protein in the liver and muscle increased as the protein content of the diet increased. The ratio of N in the organs (with the exception of the spleen and pancreas) to N in the carcass was highest for lambs given the diet with least protein (diet A).

Effects of rapeseed-meal and fish-meal supplementation of maize silage-based diets upon voluntary intake, live-weight gain and wool growth of store lambs

1994 ◽  
Vol 58 (1) ◽  
pp. 49-56 ◽  
Author(s):  
M. A. Kossaibati ◽  
M. J. Bryant
Keyword(s):  
Weight Gain ◽  
Fish Meal ◽  
Control Diet ◽  
Live Weight ◽  
Rapeseed Meal ◽  
Metabolizable Energy ◽  
Energy Utilization ◽  
Maize Silage ◽  
Live Weight Gain ◽  
Wool Growth

AbstractThirty-six individually penned lambs (mean live weight 32·4 (s.d. 2·27) kg) were offered maize silagead libitumand one of three concentrate mixes, two of which contained extracted rapeseed meal (control and HR) and the other fish meal (FM). The concentrates were given according to live weight and in sufficient quantities to provide proportionately about 0·4 of the dry matter (DM) intake of the lambs. The dietary concentrations of nitrogen (N) g/kg DM were 22·4, 27·4 and 27·5 and of rumen undegradable N 6·6, 7·3 and 11·6 for the control, HR and FM diets respectively.Both the HR and FM diets depressed maize silage intakes compared with the control during the first 21 days (P < 0·05) and lambs given the FM diet continued to have lower intakes than control lambs (P < 0·05) throughout the experiment. The live-weight gain of HR lambs was considerably depressed in comparison with the control and FM lambs during the first 21 days of the experiment (P < 0·05). Overall HR lambs gained weight more slowly than control and FM lambs up to 45 kg live weight but the difference was not statistically significant. Food conversion ratio was better for FM than HR (P < 0·01). There were no treatment differences in wool growth.The results obtained provide little evidence that fish meal had any beneficial effects upon lamb growth compared with the control diet except a possible increase in the efficiency of metabolizable energy utilization.

The effects of dose and method of administration of biosynthetic bovine somatotropin on live-weight gain, carcass composition and wool growth in young lambs

1987 ◽  
Vol 44 (3) ◽  
pp. 405-414 ◽  
Author(s):  
I. D. Johnsson ◽  
D. J. Hathorn ◽  
R. M. Wilde ◽  
T. T. Treacher ◽  
B. W. Butler-Hogg
Keyword(s):  
Weight Gain ◽  
Shoulder Joint ◽  
Abdominal Cavity ◽  
Live Weight ◽  
Carcass Composition ◽  
Bovine Somatotropin ◽  
Curvilinear Relationship ◽  
Live Weight Gain ◽  
Fat Depots ◽  
Wool Growth

ABSTRACTExogenous bovine pituitary somatotropin (GH) can influence markedly body composition in fattening lambs. However, neither the effects of biosynthetic somatotropin nor the effects of dose and method of administration have been reported. Fifty Dorset-cross lambs (female and castrated male) were given concentrate ad libitum and treated between 10 and 22 weeks of age with biosynthetic bovine somatotropin either dissolved in buffer and injected subcutaneously (s.c.) in proportion to body weight (0·025, 0·1 or 0·25 mg/kg per day), dissolved in buffer and continuously infused s.c. (0·1 mg/kg per day) or suspended in olive oil and injected s.c. (0·1 mg/kg per day), and compared with 10 untreated control lambs. Somatotropin had little effect on live-weight gain (controls = 228 g/day; final live weight 37 kg), food intake and food conversion efficiency, and only marginally increased the weight of muscle and bone dissected from the shoulder joint. The weights of the major fat depots in the abdominal cavity and of fat dissected from the shoulder joint were linearly related to dose of somatotropin (P < 0·001). Lambs given the highest dose had less visceral fat (1·18 v. 2·84 kg; P < 0·001) and proportionately less fat (285 v. 374 g/kg; P < 0·001) and more muscle (542 v. 447 g/kg) and bone (172 v. 149 g/kg; P < 0·001) in the shoulder joint than control lambs. There was a positive curvilinear relationship (P < 0·01) between clean wool growth (mid-side patch sample) and dose; lambs injected daily with 0·1 mg somatotropin per kg grew one-third more wool than control lambs. Method of administration affected plasma somatotropin profiles but had no significant influence on any of the responses measured. The anabolic actions of somatotropin may have been limited in this experiment by a low sodium concentration in the diet. It is concluded that the lipolytic/anti-lipogenic effect of somatotropin can occur in the absence of conditions conducive to the stimulation of muscle protein deposition and that the response is dose dependent but not influenced by method of administration of the hormone.

The Effects of Perennial Grasses, Stocking Rate and Rainfall on Sheep Production in a Semi-Arid Woodland of Eastern Australia.

1999 ◽  
Vol 21 (2) ◽  
pp. 199 ◽  
Author(s):  
D Freudenberger ◽  
A Wilson ◽  
R Palmer
Keyword(s):  
Weight Gain ◽  
Live Weight ◽  
Perennial Grasses ◽  
Green Leaf ◽  
Stocking Rate ◽  
Live Weight Gain ◽  
Wool Growth ◽  
Sheep Production ◽  
Stocking Rates ◽  
Semi Arid

A grazing study was conducted in a semi-arid mulga (Acacia aneura) woodland to determine the relative importance of variables controlling sheep production in this environment. The study was based on six sheep stocking rates (0.3-0.8 sheeplha) with the exclusion of other large herbivores including kangaroos and feral goats. The availability of forage and its components, together with the wool growth and live weight of the sheep were measured every three months for seven years from October 1986. Annual rainfall accounted for 60% of the annual variation in live weight gain per head and 79% of the variation in wool growth per head. Stocking rate accounted for an additional 10% of the variation. Rainfall accounted for this large proportion of variation by its strong influence on the yield of green leaf which accounted for 78% of the variation in live weight gain and 66% of the variation in wool growth. Green leaf was a determinant of sheep production because of its superior crude protein content and digestibility compared to dry leaf and stem. The species comprising this green leaf had an influence on sheep production only during drier years when the presence of palatable perennial grasses became important to sheep production. The frequency and yield of perennial grasses were greatly diminished at high stocking rates. This change in forage composition caused a decline in sheep productivity as detected by a loss of linearity in the relationship between stocking rate and live weight gainlhead. We conclude that adjusting stocking rates is required in this environment for maintenance of long-term sheep productivity and landscape function. The loss of palatable perennial C, grasses over much of the region has reduced livestock productivity and increased the variability in forage availability. Stock numbers should be adjusted at critical times to avoid losing perennial grasses that are important for sheep production in drier years. New grazing strategies are required to restore these grasses to the region.

Influence of cotton-seed meal and barley grain supplements on intake, digestion, live-weight gain and wool growth in sheep fed NaOH-treated oat and wheat straw diets

1987 ◽  
Vol 108 (1) ◽  
pp. 211-219 ◽  
Author(s):  
K. Amaning-Kwarteng ◽  
R. C. Kellaway
Keyword(s):  
Weight Gain ◽  
Wheat Straw ◽  
Cotton Seed ◽  
Live Weight ◽  
Barley Grain ◽  
Seed Meal ◽  
Live Weight Gain ◽  
Cotton Seed Meal ◽  
Wool Growth ◽  
Weight Gains

SummaryGrowth and digestibility trials were conducted to investigate responses of young cross-bred sheep to alkali-treated straws and supplements. Oat and wheat straws were coarsely milled, sprayed with NaOH solution and then sprayed with a solution containing N, S, P, Cu and Co, and mixed with powdered limestone. The treated straws were fedad libitumwith no supplement (0) or with 150 g/day of either cotton-seed meal (CSM) or whole barley grain (B). In a preliminary trial to study the effect of frequency of ort collection on intake of treated straw, consumption decreased (P< 0·05) when frequency of ort collection was reduced from once daily to once weekly. This was associated with an increase in the neutral detergent fibre content of the orts. During the growth trial, which lasted 105 days, intake of treated straw increased by 34%.When no supplement was fed, digestibility of treated oat straw was higher (P < 0·05) and dry-matter intake lower (P< 0·05) than that of treated wheat straw. However, calculated intakes of metabolizable energy (ME) and measurements of growth and wool production were similar on the two straws (P> 0·05).When supplements were fed, there was no effect on intake of the treated straws. Mean live-weight gains were 51·4, 80·2 and 77·3 g/day on treatments 0, CSM and B respectively (P< 0·01). This was associated with higher intakes of ME (P< 0·01) which accounted for 73% of the variation in live-weight gains. Mean clean wool growth was 7·6, 10·5 and 9·3 g/day on treatments 0, CSM and B respectively (P< 0·01). This effect was associated more with nitrogen (N) absorption than with ME intake (80 and 48% of the variation in wool growth respectively).It was concluded that the treated straws provided sufficient nutrients for modest growth in young sheep, that the supplements had no effect on intake of the treated straws and that additional live-weight gain and wool growth obtained by feeding CSM and B were associated with energy intake and nitrogen absorbed respectively.

scholarly journals Copper metabolism in growing sheep given kale (Brassica oleracea) and ryegrass (Lolium perenne)–clover (Trifolium repens) fresh forage diets

1983 ◽  
Vol 50 (2) ◽  
pp. 281-289 ◽  
Author(s):  
T. N. Barry ◽  
K. R. Millar ◽  
G. Bond ◽  
S. J. Duncan
Keyword(s):  
Weight Gain ◽  
Cytochrome Oxidase ◽  
Oxidase Activity ◽  
Hind Limb ◽  
Live Weight ◽  
Sod Activity ◽  
Live Weight Gain ◽  
Cytochrome Oxidase Activity ◽  
Wool Growth ◽  
Hind Limb Muscle

1. Kale (Brassica oleracea) and ryegrass (Lolium perenne)–clover (Trifolium repens) pasture grown under similar soil conditions were grazed in the vegetative state by growing lambs of 23·6 kg initial live weight for 24 weeks. Forty-eight lambs grazed each forage. The kale and pasture contained respectively 4 and 14 mg copper/kg dry matter (DM), 7·2 and 3·1 g total sulphur/kg DM and 0·4 and 1·1 mg molybdenum/kg DM.2. Subcutaneous injections of Cu (12 mg) were given to half the animals grazing each forage during weeks 1, 6, 12 and 18.3. All ninety-six animals were slaughtered at the end of the experiment and an additional group of twelve animals was slaughtered when the experiment commenced. Liver Cu was determined on all slaughtered animals and heart muscle cytochrome oxidase (EC 1.9.3.1) activity on those slaughtered at week 24. Blood samples removed at 6-week intervals were assayed for activity of superoxide dismutase (EC 1.15.1.1; SOD) and serum Cu concentration determined. Wool growth, live-weight gain and cytochrome oxidase activity of biopsied hind-limb muscle were also measured at 6-week intervals.4. Control animals grazing pasture showed an accumulation of total liver Cu during the experiment. Animals grazing this diet and given Cu injections showed an additional accumulation of liver Cu equivalent to the supplementary Cu administered, but Cu supplementationdid not affect the activity of any of the Cu-containing enzymes measured and did not affect live-weight gain or wool growth.5. Control animals grazing kale showed a depletion of total liver Cu and reductions in serum Cu concentrations during weeks 18 and 24. However, cytochrome oxidase activity inheart and hind-limb muscle was similar to that of pasture-fed lambs. Blood SOD activity was reduced by kale feeding, but a laboratory study showed this enzyme was not inactivatedby dimethyl disulphide produced from rumen fermentation of S-methyl-L-cysteine sulphoxide(SMCO) which occurs in kale.6. Cu supplementation of kale-fed lambs had no effect on hind-limb cytochrome oxidaseactivity, but considerably increased total cytochrome oxidase activity in the heart and minimized the reduction in blood SOD activity. Both are considered to represent defence mechanisms against the haemolytic anaemia caused by SMCO. However, Cu supplementation did not affect live-weight gain or wool growth.7. The proportion of injected Cu not recovered in the liver at slaughter was greater for lambs grazing kale than ryegrass–clover pasture and the same result was calculated from Barry et al. (1981) for growing cattle. It was therefore concluded that Cu requirements must be greater for growing sheep and cattle grazing kale than ryegrass-clover pasture.

The effect of inbreeding on feed consumption and utilisation by sheep

1967 ◽  
Vol 9 (3) ◽  
pp. 359-364 ◽  
Author(s):  
J. M. Doney
Keyword(s):  
Weight Gain ◽  
Live Weight ◽  
Feed Consumption ◽  
Live Weight Gain ◽  
The Third ◽  
Third Phase ◽  
Wool Growth ◽  
Voluntary Intake ◽  
Pelleted Diet ◽  
Two Phases

Twelve inbred (coefficient of inbreeding 25%) and 12 outbred, singlereared, Scottish Blackface castrated male lambs were taken at six months of age from amongst the progeny of three rams. They were housed and fed individually on a pelleted diet in three separate phases. In the first two phases restricted amounts were offered. These were calculated to produce, firstly, a small rate of live-weight gain and, secondly, a small rate of live-weight loss. In the third phase feed was offered to maximum voluntary intake during 2 two-hour periods daily.On restricted intakes there were no significant differences between the groups. In the third phase the outbred sheep consumed 17% more feed than the inbred group and the daily rates of live-weight gain and wool growth were 33% and 27% higher, respectively. Since the inbred lambs were smaller, the voluntary intake per unit live-weight did not differ significantly between groups.The estimated requirements of feed for maintenance (20·1 ± 0·4 and 21·9±0·6 g./kg. live-weight, respectively, for the outbred and inbred groups) differed significantly. There were no apparent differences in the estimated efficiency of conversion of available surplus feed to body tissue or wool growth.

scholarly journals Further studies on the effects of the presence or absence of protozoa in the rumen on live-weight gain and wool growth of sheep

1984 ◽  
Vol 52 (3) ◽  
pp. 607-611 ◽  
Author(s):  
S. H. Bird ◽  
R. A. Leng
Keyword(s):  
Weight Gain ◽  
Feed Intake ◽  
Weight Change ◽  
Live Weight ◽  
Live Weight Gain ◽  
Wool Growth ◽  
Large Populations

1. Lambs were given a diet of oaten chaff-sucrose-fishmeal(48:48:4, w/w) and either 60 (diet A) or 120 (diet B) g urea/kg sucrose in the diet. All animals were defaunated and half were refaunated. Each group of lambs (faunated and defaunated) was then divided into two groups and given diet A or diet B. Feed intake, wool growth and live-weight change were monitored over a 182 d period.2. The level of urea supplementation had no effect on wool growth or live-weight gain.3. Defaunated lambs gained live weight at a higher rate (9%,P< 0.06) and grew 37% more wool (P< 0.01) than the lambs with large populations of protozoa in their rumens.

Sign in / Sign up

Export Citation Format

Share Document