Factors limiting the intake of feed by sheep. III. The mean retention time of feed particles in sections of the alimentary tract

1968 ◽  
Vol 19 (2) ◽  
pp. 261 ◽  
Author(s):  
RH Weston

The mean retention time of feed particles in the alimentary tract of sheep was measured by means of a stained-particle technique, when lucerne hay or a diet of wheaten straw + wheaten hay (1 : 1) was offered ad libitum. The levels of intake of the straw diet and lucerne hay were equivalent to 11.8 and 25.8 g organic matter/day/kg body weight. The mean retention time of particles in the entire alimentary tract when the straw diet was offered was 57.5 hr, this consisting of 36.3 hr in the rumen + omasum and 21.2 hr in the abomasum + intestines. The retention time in the rumen + omasum was calculated to consist of (a) 19.7 hr during which the particles were being degraded to a size at which transfer from the rumen could be readily effected, and (b) 16.6 hr of residence in the rumen + omasum as small particles. With lucerne hay, the retention times were shorter: small particles spent 10.8 hr in the rumen + omasum and retention time in the abomasum + intestines was 16.1 hr. It was calculated that only a small proportion of the difference between the straw diet and lucerne hay in organic matter intake could be attributable to differences between the diets in the rate of removal of finely divided particles of organic matter from the rumen.

1956 ◽  
Vol 47 (2) ◽  
pp. 196-204 ◽  
Author(s):  
Elizabeth J. Castle ◽  
M. E. Castle

A method for measuring the rate of passage of meal through the alimentary tract of pigs by feeding a stained marker is described. The results are given of sixty-four experiments made under standardized conditions on four fattening pigs with live weights ranging from 49·9 to 185·5 lb. and six experiments on a sow weighing 500 lb.Results were expressed by means of excretion curves. These were sigmoid in shape and from them a value termed R, the mean retention time (hr.) of all the stained particles in the alimentary tract, directly proportional to the area to the left of the curve, was calculated.In the fattening piga the first appearance of the marker in the faeces occurred 10–24 hr. after feeding, and the mean 5 and 95% excretion times were 21 and 53 hr. respectively. The marker was completely excreted after approximately 80–90 hr. The R value averaged 34·2 hr.A marker fed at the morning feed (9 a.m.) had earlier 5 and 95% excretion times and the R value was significantly smaller.There was no statistically significant relationship between the R values and live weight, digestibility of the dry matter of the ration or the dry-matter content of the faeces.In the sow the 5 and 95% excretion times were 38 and 68 hr. respectively, and the R value averaged 51·1 hr.Counts of stained particles in the intestines of two of the pigs after slaughter showed that food was delayed mainly in the large intestine.


1970 ◽  
Vol 24 (1) ◽  
pp. 291-296 ◽  
Author(s):  
R. J. Bawden

1. The mean retention time of stained food residues was longer in sheep maintained on a chopped straw ration than in sheep maintained on a chopped lucerne ration.2. Infection of sheep with 1500 infective Oesophagostomum columbianum juveniles was associated with increased mean retention times.3. The extent to which the mean retention times were increased was associated with the diet and mode of infection of the sheep.4. It was noted that an increase in mean retention time following infection was associated with a general decrease in food intake per kg live eight0.75.5. The results are discussed in relation to the pathogenesis and survival of O.columbianum infections in sheep.


1957 ◽  
Vol 49 (1) ◽  
pp. 106-112 ◽  
Author(s):  
Elizabeth J. Castle ◽  
M. E. Castle

1. Four replicated experiments were made to determine the rate of passage of meal through the alimentary tract of pigs on different feeding treatments. In each experiment stained meal was used and the results were expressed by means of excretion curves. From these, mean retention times (R values) were calculated. All the curves were of a similar sigmoid shape.2. A significant inverse relationship was found between the mean retention time and the total weight (meal plus water) of the ration. This relationship was found when (a) the weight of meal was constant and the weight of water was varied, (b) the weight of water was constant and the weight of meal was varied, and (c) the total combined weight of meal and water (at the same ratio) was varied.3. The digestibility of the dry matter and crudec protein in Exps. 1–3 was not altered greatly as a result of the different feeding treatments.4. In Exp. 4, similar rates of passage were found in pigs fed on the two rations of widely different digestibilities.5. The dry-matter content of the faeces of the pigs was remarkably constant over a wide range of water and food intakes when using the same meal.


1991 ◽  
Vol 66 (3) ◽  
pp. 399-405 ◽  
Author(s):  
K. Katoh ◽  
Y. Kajita ◽  
M. Odashima ◽  
M. Ohta ◽  
Y. Sasaki

The mean retention time (MRT) of stained hay through the whole digestive tract and its digestibility were measured in Japanese sika deer (Cervus nippon) and were compared with those in sheep when lucerne (Medicago sativa) hay was fed at 10, 20 and 30 g/kg body-weight. The recoveries in faeces of plastic particles with five specific gravities were also measured in deer. MRT for deer was significantly shorter than that for sheep at 10 and 20 g/kg feeding levels. The digestibilities of dry matter, organic matter, and neutral-detergent fibre were significantly lower for deer than for sheep at 30, 30 and 10 g/kg feeding levels respectively. The recovery rates of plastic particles were increased, but the ruminated rates were decreased, with increasing specific gravity in deer. These results suggest that the lower digestibility of lucerne hay in Japanese deer may be due to a shorter MRT compared with sheep.


2001 ◽  
Vol 72 (1) ◽  
pp. 209-221 ◽  
Author(s):  
E. Molina ◽  
A. Ferret ◽  
G. Caja ◽  
S. Calsamiglia ◽  
X. Such ◽  
...  

AbstractTwo experiments were carried out with pregnant (experiment 1) and lactating ewes (experiment 2), to compare dry-matter (DM) intake, and total tract apparent digestibility, digesta kinetics and weight of digestive tract contents of Lacaune and Manchega sheep, with the aim of explaining possible differences between the breeds in voluntary food intake. In experiment 1, 20 3-year-old single-bearing pregnant ewes, 10 Manchega and 10 Lacaune, were permanently housed for the last 10 weeks of pregnancy. The diet used consisted of lucerne hay, offeredad libitum, supplemented with 0·3 kg/day of concentrate. DM and digestible DM intake per kg M0·75were higher (P< 0·01) in Lacaune than in Manchega sheep. Breed did not affect total tract apparent digestibility, fractional rates of passage, transit time, total mean retention time, or weight of digestive tract contents. Changes in body weight and body condition score were similar between breeds. In contrast, Lacaune lambs tended (P= 0·09) to weigh less than Manchega lambs, suggesting genetic differences in the energy utilization between breeds in late pregnancy. Higher DM intake observed in Lacaune sheep may have been related to a higher energy demand for mammary development. In experiment 2, 32 3-year-old lactating multiparous ewes, 16 Manchega and 16 Lacaune, were permanently housed during the first 12 weeks of lactation. The experimental diet used was based on a mixture of maize silage and dehydrated lucerne (10: 1, fresh weight basis), offeredad libitum, and supplemented with 0·8 kg/day of concentrate. Milk, fat and protein yield as well as DM and digestible DM intake in Lacaune ewes was higher (P< 0·01) than in Manchega ewes. DM intake was constant in Lacaune sheep with advancing lactation, while in Manchega sheep DM intake decreased. Throughout this period Lacaune ewes lost 0·5 kg of body weight while Manchega gained 4·4 kg. Breed did not affect either apparent digestibility of DM, organic matter and neutral-detergent fibre, or fractional rates of passage, transit time and total mean retention time. The weight of total tract digestive contents was greater (P< 0·05) in Lacaune than in Manchega sheep, particularly in the reticulo-rumen. Results suggest that the scheme of selection in Lacaune dairy sheep has increased milk yield together with voluntary food intake, the latter being associated with an increase in the rumen fill capacity. The higher milk yield of Lacaune ewes cannot be attributed to the higher DM intake only; other factors, i.e. mobilization of fat reserves, are required to support this higher milk output.


1980 ◽  
Vol 94 (1) ◽  
pp. 209-218 ◽  
Author(s):  
C. G. Wernli ◽  
R. J. Wilkins

SummarySilage, dried-grass wafers and dried-grass pellets all prepared from a single crop of perennial ryegrass were given ad libitum as sole diets to six rumen-fistulated wether sheep.Feed intake, intake of digestible nutrients and the concentration of volatile fatty acids (VTA) in the rumen were lowest with silage, highest with pellets and intermediate with wafers. Conversely, digestibility, eating and ruminating time per kg D.M. consumed, rumen pH, the rate of D.M. and cellulose digestion in the rumen and the mean retention time of digesta in the alimentary tract were highest for silage, intermediate for wafers and lowest for pellets. The pattern of rumen fermentation differed significantly between silage and the dried-grass treatments. The rumen fluid contained higher proportions of acetic, iso-butyric, n-valeric and iso-valeric acids, but lower proportions of propionic and n-butyric acids with silage than with dried grass. Differences in rumen. VFA between the two forms of dried grass were small. Nitrogen retention was lowest for the silage treatment and this was associated with a high concentration of ammonia in the rumen.Low nitrogen status with silage could have limited voluntary intake, whereas the difference in intake between the wafer and pellet treatments probably arose from differences in the retention time of digesta in the alimentary tract.


1960 ◽  
Vol 11 (1) ◽  
pp. 75 ◽  
Author(s):  
M Wodzicka

The monthly wool growth of three groups of rams was studied at Beltsville, Maryland. Group I received natural daylight (at 38° 53' N.) and was shorn monthly. Group II had a 7:17 hours of daylight to hours of darkness rhythm and was shorn every 6 months, once in winter and once in summer. Group III received natural daylight and was likewise shorn every 6 months. The rams of all groups produced more wool in summer than in winter. This difference was significant (P<0.001). The mean body weight and food intake were both greater in the winter months, which indicated that the seasonal rhythm of wool growth was not a consequence of poorer feeding in winter. The rams which were shorn monthly (group I) grew considerably more wool than the other two groups, but the difference was not statistically significant. The short-day treatment of group II did not increase the annual wool production nor decrease the seasonal rhythm of wool growth. The balance of evidence from this and other experiments indicates that temperature rather than light controls the seasonal rhythm of wool growth.


2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Enerst C. Ohanu ◽  
Paul C. Inyang-Etoh

Amebiasis caused by <em>Entamoeba histolytica</em> is a major public health problem in tropical and subtropical countries. Treatment failure with specific chemotherapy has been reported suggesting the possibility of drug resistance. This study investigated the anti-amoebic effects of four plant extracts on cecal amebiasis in rats. The cecal amebiasis was induced by the injection of 3.0×105 troph/mL of <em>E. histolytica</em> parasite directly into the rat’s caecum. A total of 137 rats were used for these studies; five rats in each group for both positive and negative control, 15 rats in each group to test the four plant extracts and metronidazole. The infected rats were treated for cecal amebiasis using each of the four plant extracts at graded doses of 100 mg/kg, 200 mg/kg and 400 mg/kg and with metronidzole at a dose of 62.5 mg/kg,100 mg/kg and 125 mg/kg for five consecutive days. The efficacy of the four plant extracts were evaluated based on Neal’s, 1951 method. The plant extracts of Garlic, <em>Guava</em>, Pawpaw and Pumpkin at 400 mg/kg and 200 mg/kg body-weight gave a cure rate of 80%, 100%, 60%, 40% and 40%, 80%, 40%, 0%, respectively. The mean parasite count in the cecal contents of the treated rats at a dose 400 mg/kg were 18.5±1.6, 0.0±0.0, 33.3±1.8 and 49.5±4.0, respectively. The difference was statistically significant (P&lt;0.05). This study has revealed that Guava at a high dosing level (400 mg/kg body weight) is as good as the standard drug in reducing the both parasite load (probably with limited side effect).


2014 ◽  
Vol 92 (3) ◽  
pp. 1099-1109 ◽  
Author(s):  
J. G. L. Regadas Filho ◽  
L. O. Tedeschi ◽  
R. A. M. Vieira ◽  
M. T. Rodrigues

1982 ◽  
Vol 24 (3) ◽  
pp. 347-360 ◽  
Author(s):  
A. de Padua Deodato ◽  
E. J. Eisen ◽  
J. M. Leatherwood

Polygenic obese (M16), nonobese (ICR) and reciprocal crossbred (M16 male × ICR female and ICR male × M16 female) mice were fed ad libitum diets containing 1, 5 or 25% fat from 3 to 10 weeks of age. Epididymal and subcutaneous fat depot weights (E, S) and depot weights as a proportion of empty body weight (E%, S%) were used as measures of adiposity at 6 and 10 weeks of age. Genetic differences in adiposity among the four populations were partitioned into average direct (a), average maternal (m) and direct heterotic (h) effects. Line M16 was greater than ICR at both 6 and 10 weeks in E (81% at 6 weeks and 114% at 10 weeks), S (82%, 73%), E% (27%, 37%) and S% (26%, 12%). Average direct genetic effects, as determined by a, accounted for 60% of the M16 vs. ICR line difference in E and S at six weeks, the remainder of the difference being due to m. The major portion of the line difference in E% and S% at 6 weeks was accounted for by m. At ten weeks of age, most of the line difference in E, S, E% and S% was due to additive direct genetic effects while the contribution of maternal genetic effects was negligible. Heterosis was sizeable for all measures of adiposity, varying from 10.8% in S% at 10 weeks to 26.8% in E at six weeks, possibly indicating the presence of directional dominance. E and E% increased significantly with the increase in dietary fat percent, but S and S% were not affected. Interactions of genotype with level of dietary fat percent were not significant for the epididymal or subcutaneous fat depot weights or proportional weights.


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