I . The concentrations of volatile fatty acids (VFA) in the rumen and caecum were compared when sheep were given barley or dried grass. The molar proportions of VFA in the caecum resembled those in the rumen except that the proportions of isobutyric and isovaleric acids were higher in caecal than in rumen fluid indicating an extensive breakdown of protein during fermentation in the caecum.2. The capacity for starch digestion in the large intestine was studied in two sheep receiving dried grass. Starch was infused into the caecum, the amount given increasing by daily increments of 20 g until 300 g daily were infused. Infused starch in excess of 138 g daily largely appeared in the faeces, indicating a limited but substantial capacity for starch fermentation in the large intestine. The infusion caused a marked increase in the molar proportion of butyric acid.3. Determinations made with a single sheep showed that the infusion of starch into the caecum caused large changes in the microflora, and species similar to Butyrivibrio became prevalent. The viable count on a starch medium was increased by 83 % by starch infusion.4. The infusions of starch increased the excretion of nitrogen in the faeces from 5.8 to 9.0 g daily. Using a fractionation procedure it was shown that when IOO g of starch were fermented in the large intestine the ' bacterial and endogenous debris' nitrogen increased by about 1.0 g.When starch was given orally to two sheep the increase in this fraction was about 0.4g nitrogen/Ioo g starch digested.5 . It is suggested that dietary factors that cause changes in the site of fermentation from the rumen to the caecum will render less microbial nitrogen available to the host animal per unit of carbohydrate fermented and decrease the apparent digestibility of nitrogen.
I . In one experiment the effect on rumen pH of feeding with restricted amounts of whole or pelleted barley was studied. With whole barley there was little variation in rumen pH associated with feeding time, but with pelleted barley the pH decreased from about 7.0 before feeding to about 5.3, 2-3 h after feeding.2. The rate of disappearance of dried grass during incubation in the rumens of sheep receiving either whole or pelleted barley was studied in a second experiment. After 24 h incubation only 423 mg/g incubated had disappeared in the rumen of sheep receiving pelleted barley while 625 mg/g incubated had disappeared when it was incubated in the rumen of sheep receiving whole barley.3. The voluntary intake of dried grass by lambs was studied in a third experiment when they received supplements of either 25 or 50 g whole or pelleted barley/kg live eight^"^. At the high level, pelleted barley reduced intake of dried grass by 534 g/kg but whole barley reduced it by only 352 g/kg. The digestibility of acid-detergent fibre was reduced more by pelleted barley than by whole barley but there was a tendency for a small increase in digestibility of the barley due to processing.4. The implications of these findings on supplementation of roughages with cereals are discussed.
Fourteen patients with hypodontia and the ocular features of the Rieger syndrome were examined for the presence of systemic anomalies. A periumbilical defect that consisted of failure of the periumbilical skin to involute was seen in ten of the thirteen evaluated for the defect. Three others had scars over the umbilical area and had a history of surgery for herniation. In addition, four males in one family and one male from another family had hypospadias. None of several other anomalies reported to be components of the Rieger syndrome by other authors was detected in the fourteen patients. The mode of inheritance in the familial cases studied was compatible with autosomal dominance. The results of this study indicate that the Rieger syndrome is an autosomal dominant syndrome whose cardinal features are hypodontia, goniodysgenesis, and failure of the periumbilical skin to involute properly.
The concentrations of dry matter, crude protein, fat and ash and of Ca, P, Mg, Na and K were determined for 22 sets of twin foetuses, 33 of triplets and 11 of quadruplets of known gestational ages within the range 55-145 days. In addition, determinations were made of the concentrations of dry matter, crude protein, fat and ash in their associated placentae and empty uteri, and of dry matter, nitrogen, energy and ash in the foetal fluids. The dry matter, crude protein and fat concentrations in the placentae increased with foetal age and decreased with increasing litter size. Ash concentrations were unaltered. There was no effect of litter size or foetal age on the concentration of nutrients in the empty uteri. Dry matter and nitrogen concentrations in the fluids increased with foetal age but were independent of litter size, whereas ash concentrations increased with litter size but not with age.The form of the mathematical model for foetal growth is considered in relation to the estimation of rates of accretion and the estimation of the differences in composition to be expected between foetuses that are heavy and others that are light relative to their age. When the weights of the foetal constituents were fitted by Gompertz equations extended to include foetal weight as an allometric term, the effects of litter size on foetal composition could be estimated from the foetal weights for each size of litter. Concentrations of dry matter and of most constituents in the foetuses became less as numbers of foetuses increased, irrespective of stage of gestation.A description of the changing composition of the growing foetuses was provided by specific growth rates calculated from the fitted equations. With minor exceptions, derived estimates of foetal concentrations of each constituent were found to agree quite well with most previously published estimates for ovine foetuses, but similar agreement on daily accretion rates was not to be expected in view of the sensitivity of such estimates to the choice of model for foetal growth. Rates of accretion in the gravid uterus increased up to about 5 weeks before parturition and tended to level off thereafter, but most of them still increased slightly over the last 2 weeks, even in ewes bearing triplets or quadruplets. Taking account of the changes in the maternal body of the ewes, it was concluded that although the prolific ewes incurred a substantial energy deficit, and could not have consumed sufficient of the diet to avoid this, their intakes in late pregnancy were nevertheless adequate to support the high rates of accretion of protein and of minerals in the gravid uterus.weeks of gestation, and found significant effects of htter size on the linear regressions of mineral Although there are several sets of observations concentrations on foetal age. Rattray et al. (1974) on the chemical composition of lamb foetuses or of measured the main chemical constituents of the entire gravid uterus over a range of gestational foetuses, placentae, foetal fluids and uteri in nine age, almost...
I . Lambs fitted with cannulas in the abomasum, terminal ileum and caecum were used to study the digestion of starch and dry matter when rations with high starch content were given. Polyethylene glycol was used as an indigestible reference substance.2. In Expt I reduction in level of feeding from an estimated ad lib. intake to 70% of this level reduced the amount of dietary starch escaping fermentation in the rumen from 6.8 to 4.4 % of intake on a barley diet and from 12.8 to 7.7 % on a diet consisting of 40 % dried grass and 60 yo barley. Inclusion of 40% chopped dried grass in the diet increased the amount of dietary starch escaping fermentation in the rumen. There appeared to be a linear relationship between the concentrations of starch in abornasal and ilcal dry matter, indicating a limited capacity for starch digestion in the small intestine. 3. In Expt 2 a barley diet was compared with diets based on flaked maize, ground maize or cracked maize. With these diets the percentage of dietary starch escaping fermentation in the rumen was respectively 6.2, 5.4, 12.1 and 1 4 2 , showing that more starch escapes fermentation with uncooked maize diets than with barley diets. The molar proportions of volatile fatty acids produced by fermentation in the caecumwere apparently influenced by the amount of starch passing to the intestines. The highest proportion of acetic acid (78 %) was associated with 4.5 % of starch in abomasal dry matter, and the lowest proportion (57 yo) was associated with 20.1 % of starch in abomasal dry matter.5. The possible relationships between the extent of fermentation in the rumen and energy and nitrogen metabolism are discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.