Effects of a concurrent infection of Trichostrongylus colubriformis on the productivity and physiological and metabolic responses of lambs infected with Ostertagia circumcincta

1982 ◽  
Vol 33 (1) ◽  
pp. 131 ◽  
Author(s):  
JW Steel ◽  
WO Jones ◽  
LEA Symons
Keyword(s):  
Nitrogen Utilization ◽  
Metabolic Responses ◽  
Concurrent Infection ◽  
Albumin Synthesis ◽  
Trichostrongylus Colubriformis ◽  
Infection Period ◽  
Plasma Loss ◽  
Wool Growth ◽  
Concurrent Infections ◽  
Dose Levels

Weaner lambs were infected for 16 weeks with 900 or 3000 Trichostrongylus colubriformis larvaelweek alone, with 38 000 Ostertagia circumcincta larvaelweek alone, or with the two parasites concurrently at these dose levels. Concurrent infections with T. colubrifovmis, which when given alone had no significant effect, reduced liveweight gain by 15 kg over the 16-week infection period compared with a 6-kg reduction in liveweight of lambs infected with O. civcumcincta alone. T. colubvifovmis when given alone did not affect wool growth, but with concurrent infections wool growth was reduced by up to 66% compared with a 25 % reduction in lambs infected with O. circunzcincta alone. This greater loss of productivity in concurrent infections was principally due to reduced food consumption, and was exacerbated by a substantial decrease in the efficiency of retention of apparently digested nitrogen. These effects were accompanied by an elevated gastroenteric plasma loss, and a concomitant decrease in albumin synthesis which together were considered responsible for the more pronounced hypoalbuminaemia observed in lambs with concurrent infections. Reasons for impaired nitrogen utilization in concurrently infected lambs are discussed.

Effects of level of larval intake on the productivity and physiological and metabolic responses of lambs infected with Trichostrongylus colubriformis

1980 ◽  
Vol 31 (4) ◽  
pp. 821 ◽  
Author(s):  
JW Steel ◽  
LEA Symons ◽  
WO Jones
Keyword(s):  
Growth Rate ◽  
Food Consumption ◽  
Muscle Protein ◽  
Nitrogen Retention ◽  
Infected Sheep ◽  
Albumin Concentration ◽  
Maximal Effect ◽  
Trichostrongylus Colubriformis ◽  
Infection Period ◽  
Wool Growth

The interrelationships between level of exposure to Trichostrongylus colubriformis infection, production loss, and the physiological and metabolic changes associated with the development of the disease were studied over 24 weeks in groups of weaner lambs on larval dosing regimes (LDR) of either 0, 300, 950, 3000, 9500 or 30,000 infective larvae per week. During the first 12 weeks faecal egg counts generally accorded with the level of larval dosing, but thereafter declined, and at 24 weeks worm counts showed that most animals were resistant to parasite establishment. Liveweight gain over the 24-week infection period was significantly depressed only on LDR 3000, 9500 and 30,000 being, respectively, 67, 61 and 49% of the gain on LDR 0. These differences reflected reduced rates of gain, or, on LDR 30,000, loss of weight, during the first 12 weeks; rates of liveweight gain were similar on all LDR between 12 and 24 weeks. Wool growth rate was significantly depressed on LDR 3000, 9500 and 30,000, the maximal effect being recorded during weeks 8-12, when the growth rate was reduced to 79, 47 and 44% respectively of the rate on LDR 0. Thereafter, wool growth rate on these three LDR increased and by weeks 20-24 had returned almost to the level in uninfected sheep. Food consumption was significantly depressed on LDR 3000, 9500 and 30,000, the maximal effect occurring between weeks 8 and 12 when food consumption was 71, 61 and 44% respectively of that on LDR 0. By weeks 20-24 food consumption on these LDR had returned to the level in uninfected sheep. On LDR 30,000 there was a significantly increased excretion of nitrogen (g/100 g nitrogen intake) in faeces during the 8th, 12th and 24th weeks of infection and in urine during the 4th, 8th and 12th weeks. Nitrogen retention (g/100 g nitrogen apparently digested) was significantly reduced on LDR 30,000 during the 4th, 8th and 12th weeks. Enteric loss of plasma was significantly increased on LDR 950 and above, this effect occurring earlier and being more pronounced with increasing level of larval dosing; maximal losses were recorded during the 12th week when on LDR 30,000 sheep were losing approximately four times as much plasma into the gut as on LDR 0. The development and degree of hypoalbuminaemia in infected sheep paralleled the development of enteric plasma leakage, significantly reduced albumin levels being recorded on LDR 950 and above during the 12th week. By the 24th week both enteric plasma loss and plasma albumin concentration in sheep on these four LDR had returned to values similar to those in uninfected sheep. Measurements of albumin kinetics indicated that rates of albumin turnover and irreversible loss were increased in infected sheep only during the early stages of infection. Depletion of the albumin pool was accompanied by a significantly reduced rate of irreversible albumin loss during the 12th week on LDR 3000 and above. Measurements of the RNA/DNA ratio in liver and muscle at 4, 10 and 17 weeks indicated that protein synthesis in these tissues was significantly depressed only on LDR 30,000. Catabolism of muscle protein declined concomitantly with reduced food consumption.

Effects of level of larval intake on the productivity and physiological and metabolic responses of lambs infected with Ostertagia circumcincta

1981 ◽  
Vol 32 (1) ◽  
pp. 139 ◽  
Author(s):  
LEA Symons ◽  
JW Steel ◽  
WO Jones
Keyword(s):  
Turnover Rate ◽  
Nitrogen Excretion ◽  
Metabolic Effects ◽  
Metabolic Responses ◽  
Albumin Concentration ◽  
Infective Larvae ◽  
Plasma Loss ◽  
Metabolic Functions ◽  
Wool Growth ◽  
Faecal Nitrogen

The interrelationships between level of exposure to Ostevtagia circumcincta infection, production loss and physiological and metabolic effects were examined over 24 weeks in groups of weaner lambs on larval dosing regimes (LDR) of either 0, 1200, 3750, 12000, 37500 or 120000 infective larvae per week. During the first 12 weeks, liveweight gain and wool growth were significantly depressed in lambs on both LDR 37 500 and 120000, but food consumption was significantly reduced only on the latter. Faecal nitrogen excretion was increased by both of these LDR but the efficiency of retention of apparently digested nitrogen was generally unchanged. Enteric plasma loss and albumin turnover rate were significantly increased by LL)R 120000 during the 4th week, at which time albumin concentration was most severely depressed. After the 12th week there were generally no significant effects of infection, and total liveweight gain over 24 weeks was similar for all lambs. Recovery coincided with a decline in faecal egg counts, abomasal worm counts and plasma pepsinogen concentrations. It was concluded that, under the conditions of this experiment, an intake of more than 12000 O. civcumcinctu larvae per week is necessary to have significant effects on the physiological and metabolic functions of weaner lambs with consequent losses in productivity.

Trichostrongylosis and wool growth. 2. The wool growth response of infected sheep to parenteral and duodenal cystine and cysteine supplementation

1973 ◽  
Vol 13 (63) ◽  
pp. 351 ◽  
Author(s):  
IA Barger ◽  
WH Southcott ◽  
VJ Williams
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Growth Response ◽  
Infected Sheep ◽  
Trichostrongylus Colubriformis ◽  
Intestinal Nematode ◽  
Wool Growth ◽  
Cysteine Hydrochloride ◽  
Significant Difference ◽  
Maintenance Ration

Two experiments are reported. In experiment 1, light infections with the intestinal nematode Trichostrongylus colubriformis reduced wool growth of sheep by 42 per cent compared with pair-fed controls. There was no significant difference in wool growth between those sheep given a cystine supplement as an intraperitoneal pellet and those given a daily intra-duodenal injection of cystine, although cystine was poorly absorbed from the peritoneal cavity. In experiment 2, fifteen sheep were fed a maintenance ration and their wool growth rates defined. When six of the sheep were given a daily intra-duodenal drip containing 2 g cysteine hydrochloride, and six sheep were given the same drip intravenously, their wool growth rate increased by a mean of 33 per cent compared with the wool growth of the three untreated sheep, irrespective of the route of administration of the cysteine. Three sheep in each group of six were then lightly infected with Trichostrongylus colubriformis and the wool production of all sheep was measured in the presence and absence of the daily cysteine supplement via the two routes. The infection depressed wool growth, but did not influence the wool growth response to either route of cysteine supplementation. It was concluded that the reduced wool growth induced by trichostrongylosis could not be attributed to malabsorption of cysteine. Evidence was obtained that sheep resistant to Trichostrongylus colubriformis produced less wool when subjected to a larval challenge.

Effect of nutrition, genotype, lactation and wool cover on response by grazing sheep to methionine esters and polymer-encapsulated methionine

1979 ◽  
Vol 30 (4) ◽  
pp. 711 ◽  
Author(s):  
JL Wheeler ◽  
KA Ferguson ◽  
NT Hinks
Keyword(s):  
Weight Gain ◽  
Daily Weight Gain ◽  
Wool Growth ◽  
Native Pasture ◽  
Grazing Sheep ◽  
Dose Levels ◽  
Improved Pasture

Esters of methionine added to the diet of penned sheep have been reported to increase wool growth. Four experiments were undertaken in which grazing sheep were drenched with methionine derivatives. In experiment 1 methyl methionine hydroxy analogue (MeMHA) and ethyl methionine hydrochloride (EMHCl) increased wool growth similarly, by about 30% (P < 0.001) on native pasture and 4% (P > 0.05) on improved pasture. Dosing three times per week was as effective as dosing six times per week. In experiment 2, wool growth of unsupplemented sheep on improved pasture in spring was c. 12 g/d and was not increased by the administration of MeMHA to fine- or strong-wool sheep whether lactating or dry. Daily weight gain by young lambs declined from 258 to 215 g/d when their dams were given MeMHA at 4 g/d 5 days per week (P < 0.05). Administration of methionine as MeMHA or EMHCl or in a polymer-encapsulated form at 1.25 gld gave c. 1 g/d additional wool in experiment 3; 2.5 g/d increased wool growth by c. 1.5 g/d (P < 0.001). In experiment 4, MeMHA doses of 1.25 and 2.5 g methionine equivalent per day produced no response in sheep in full wool. In shorn Merinos wool growth increased by 1.2 and 0.4 g/d, and Dorset Horn x Merinos showed a decrease of 0.5 and an increase of 1 .3 g wool/d at the two dose levels (P < 0.01). Wool growth was increased by c. 1 g/d by 1.25 g MeMHA in sheep that had received 10 mg selenium but not in control sheep. These responses are less than those reported from pen experiments in which methionine derivatives were incorporated in the diet. It is concluded that at current prices it would not be profitable to supplement grazing sheep with any of these forms of methionine.

scholarly journals EXPERIMENTAL STUDIES OF THE NASOPHARYNGEAL SECRETIONS FROM INFLUENZA PATIENTS

1921 ◽  
Vol 33 (3) ◽  
pp. 373-383 ◽  
Author(s):  
Peter K. Olitsky ◽  
Frederick L. Gates
Keyword(s):  
Experimental Studies ◽  
Type Ii ◽  
Concurrent Infection ◽  
Pulmonary Tissue ◽  
Type Iv ◽  
Concurrent Infections ◽  
Pneumococcus Type

1. Concurrent infections in the experiments described may be regarded as of accidental nature and are not causally related to the typical effects induced in rabbits by a material wholly free from ordinary bacteria. 2. The influenzal agent exerts an effect on the pulmonary tissue which encourages the invasion of the lung and subsequent multiplication there of ordinary bacteria, such as the pneumococcus, streptococcus, and Bacillus pfeifferi. 3. A similarity is believed to exist between the conditions under which concurrent infections arose in the inoculated rabbits and those which seem to favor the occurrence of concurrent infections during epidemic influenza in man. In no instance did death occur in the rabbits as a result of the uncomplicated effects of the influenzal agent alone. When death occurred in any of the inoculated animals concurrent infection of the lungs by ordinary bacteria was present. The microorganisms most commonly met with under these conditions were Pneumococcus Type IV and atypical Type II, streptococci, and hemoglobinophilic bacilli. Other kinds were encountered less often.

Efficiency of Utilization of Urea Nitrogen for Albumin Synthesis by Chronically Uraemic and Normal Man

1975 ◽  
Vol 48 (5) ◽  
pp. 379-390 ◽  
Author(s):  
R. Varcoe ◽  
D. Halliday ◽  
E. R. Carson ◽  
P. Richards ◽  
A. S. Tavill
Keyword(s):  
Renal Failure ◽  
Chronic Renal Failure ◽  
Significant Positive Correlation ◽  
Normal Subjects ◽  
Nitrogen Utilization ◽  
Urea Synthesis ◽  
Absolute Rate ◽  
Albumin Synthesis ◽  
Urea Nitrogen ◽  
Urea Metabolism

1. The relation between endogenous urea metabolism and albumin synthesis has been studied in ten patients with chronic renal failure and in four normal subjects, after single intravenous injections of [14C]urea, [15N]urea and 125I-labelled albumin. 2. The rate of urea synthesis was determined from the dynamics of plasma [14C]urea specific radioactivity and the rate of urea metabolism was estimated from the relative rates of urea synthesis and urea appearance in urine and body water. Deconvolution analysis of plasma [15N]albumin enrichment and 125I-labelled albumin radioactivity yielded the cumulative incorporation of 15N into total exchangeable albumin and enabled calculation of the absolute rate of urea nitrogen utilization for albumin synthesis. 3. Although the mean absolute rate of urea degradation in uraemic patients (3.7 mmol/h) was higher than in normal subjects (2.3 mmol/h) there was no significant positive correlation between urea degradation and plasma urea concentration. 4. In uraemic subjects, there was a significant positive correlation between urea synthetic rate and urea degradation rate. 5. The rate of utilization of urea nitrogen for albumin synthesis was low, but was very much higher in uraemic subjects (mean 83.8 μmol/h) compared with normal subjects (mean 6.4 μmol/h), as was the provision by urea of the nitrogen required for albumin synthesis in uraemic subjects (2.37%) compared with normal subjects (0.13%). 6. The efficiency of utilization of urea nitrogen for albumin synthesis was higher in the uraemic patients (1.3%) than the normal subjects (0.2%), and was higher in those patients with chronic renal failure who received a 30 g protein diet than those on 70 g of protein. A significant negative correlation was noted between efficiency of urea nitrogen utilization and the rate of synthesis of albumin. 7. These studies suggest the presence of a mechanism for the conservation of urea nitrogen in chronic renal failure which is unrelated to the extent of urea degradation, and which can only be partly explained by the higher proportion of intraluminal gut nitrogen derived from urea.

Growth and gastrointestinal nematode parasitism in lambs grazing either lucerne (Medicago sativa) or sulla (Hedysarum coronarium) which contains condensed tannins

1995 ◽  
Vol 125 (2) ◽  
pp. 281-289 ◽  
Author(s):  
J. H. Niezen ◽  
T. S. Waghorn ◽  
W. A. G. Charleston ◽  
G. C. Waghorn
Keyword(s):  
Medicago Sativa ◽  
Condensed Tannins ◽  
Average Daily Gain ◽  
Fibre Diameter ◽  
Parasite Burden ◽  
Superior Performance ◽  
Wool Fibre ◽  
Trichostrongylus Colubriformis ◽  
Wool Growth ◽  
Hedysarum Coronarium

SUMMARYTwo grazing experiments were undertaken to evaluate the effects of sulla (Hedysarum coronarium) which contains condensed tannins (CT) and lucerne (Medicago sativa), which does not contain CT, on the performance of parasitized and non-parasitized lambs. The work was carried out near Palmerston North, New Zealand in 1992 and 1993.Experiment 1 used lambs which were either genetically ‘conventional’ or ‘resistant’ to gastrointestinal nematodes and which had a naturally acquired heavy parasite burden (faecal egg count (FEC) 1300–2500 eggs per gram faeces (epg)). They were either drenched to remove all the parasites or remained undrenched when allocated to pure swards of either sulla or lucerne for the 28-day experimental period. Liveweight gains of drenched lambs were higher with sulla (mean 302 g/day) than with lucerne (mean 245 g/day; P < 0·02) and rates of gain were not reduced (P = 0·10) by genetic resistance to nematodes. Undrenched lambs had mean faecal egg counts of 1090–2220 epg after 28 days, with higher counts in lambs grazing lucerne than in those grazing sulla (P < 0·05). Lambs grazing lucerne also had a much lower average daily gain (ADG) (mean 50 g/day) than those grazing sulla (mean 206 g/day; P < 0·0001). Resistant lambs had reduced (P = 0·07) ADG in the sulla treatment only.In Expt 2, lambs with a relatively low worm burden (average FEC 250 epg) were either drenched to remove all worms or dosed with 20 000 Trichostrongylus colubriformis infective larvae and grazed on pure sulla or lucerne swards for 42 days. Drenched lambs had a similar liveweight gain (mean 190 g/day) and wool growth when grazing either sulla or lucerne. Undrenched lambs grazing sulla had a greater ADG (mean 129 g/day) than those grazing lucerne (mean −39 g/day; P < 0·0001) and a higher rate of wool growth from mid-side patches (P < 0·009) and larger wool fibre diameter (P < 0·05) than those grazing lucerne. Undrenched lambs grazing sulla had lower FECs (P < 0·05) on days 14, 21, 35 and 42 than those grazing lucerne and lower (P < 0·05) Trichostrongylus colubriformis worm burdens at slaughter. Undrenched lambs had less perineal faecal contamination when grazing sulla rather than lucerne. Parasite-induced anorexia was evident in the lambs grazing lucerne but not in those grazing sulla.These findings demonstrate that the performance of lambs infected with nematode parasites can vary substantially when given feeds of a similar chemical composition. The superior performance of lambs grazing sulla was probably caused by condensed tannins, which decrease protein degradation in the rumen and can increase post-ruminal protein availability.

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