scholarly journals Studies on the energy metabolism of the pregnant sow

1985 ◽  
Vol 53 (2) ◽  
pp. 251-265 ◽  
Author(s):  
J. Noblet ◽  
W. H. Close ◽  
R. P. Heavens ◽  
D. Brown

1. Twenty-six gilts were used in an experiment to study the effects of level of feed intake on the growth and chemical composition of the gravid uterus and mammary tissue at several stages of gestation. The animals were given either 1.8 or 2.5 kg feed/d (20 or 30 MJ metabolizable energy (ME) respectively) and were slaughtered at intervals between days 40 and 110 of gestation. The gravid uterus was dissected into fetal, placental, fluid and empty uterus components. From day 70 of gestation the mammary tissue was also dissected. The fresh weight and dry matter (DM), energy and nitrogen contents of the various tissues were determined.2. (a) With the exception of the fluid component, there was a significant increase (P < 0.01) in the fresh weight of each tissue with both stage of gestation and level of feeding. At comparable litter sizes the total weight of the fetuses in late gestation was 16% higher with the higher feed intake. (b) The DM content of the individual uterine tissues increased significantly (P < 0.01) with increase in stage of gestation so that the mean DM content of the gravid uterus increased from 74.6g/kg at day 50 to 103.1 and 159, 0g/kg at days 90 and 110 of gestation respectively. (c) Neither stage of gestation nor feeding level influenced the respective energy contents of the individual uterine tissues, when expressed per g DM. The mean energy content of the total gravid uterus was 19.5 kJ/g DM. (d) The N content (g/g fresh weight) of the tissues increased with stage of gestation and was generally higher at the higher feeding level. The mean N contents (g/g DM) of the fetal, placental, fluid and empty uterine tissues were 0.090, 0, 101, 0.098 and 0.128 respectively.3. The mammary tissue was the most variable of all the tissues investigated. Whereas the fresh weight and N content increased with stage of gestation, both the DM and energy content decreased.4. Gompertz equations were fitted to describe the effects of stage of gestation, level of feed intake and litter size on the fresh weight and chemical content of the individual uterine tissues, total gravid uterus and mammary tissue. The use of these equations for calculating the nutrient requirements of pregnancy is demonstrated.5. It was calculated that between days 50 and 110 of gestation the ME requirement for reproduction increased from 3 to 12% of maternal energy intake. The calculated requirement for protein was from 7 to 41 % of maternal dietary protein intake respectively.

1976 ◽  
Vol 16 (82) ◽  
pp. 699 ◽  
Author(s):  
JK Connor ◽  
AR Neill ◽  
KM Barram

Metabolizable energy assays using Australorp chickens were carried out on sorghum and maize hybrids grown in different regions in Queensland and harvested in different years. Relationships between metabolizable energy and the chemical composition of the grains were examined. Some comparisons also were made between the energy metabolized by different strains of chickens. The mean nitrogen-corrected metabolizable energy values and standard deviations for all maize and sorghum grains were 3770 � 154 (n = 48) and 3750 � 239 (n = 39) kcal per kg dry matter, respectively. There were significant differences in metabolizable energy values between locations and years of harvest for both grains. Significant differences were seen between sorghum hybrids, but not between maize hybrids. The interactions, hybrid x region and hybrid x year, also were significant for sorghum. Correlations between metabolizable energy and chemical composition of the grains were not sufficiently high to enable metabolizable energy to be predicted with the accuracy necessary for practical application. Chickens from a White Leghorn and two commercial broiler strains gave similar metabolizable energy values to those obtained with the Australorp chickens.


1993 ◽  
Vol 69 (3) ◽  
pp. 617-629 ◽  
Author(s):  
I. Kyriazakis ◽  
J. D. Oldham

To test the proposition that sheep are able to select a diet that meets their crude protein (N × 6.25; CP) requirements, feeds L, A, B, C and H with the same energy content (11 MJ metabolizable energy/kg feed) but different CP contents (78, 109, 141, 172 and 235 g CP/kg fresh feed respectively) were formulated. In addition, feed U, which was feed L plus 21.4 g urea/kg (CP content 132 g/kg), was also made. The feeds were offered ad lib. either singly (n 4 per treatment) or as a choice between feed H and another feed (pairs LH, AH, BH, CH and UH; n 9 per feed pair) to individually penned Suffolk × Scottish mule wether lambs, over the live-weight range 25–45 kg. On the single feeds the rates of live-weight gain were 273, 326, 412, 418, 396 and 407 g/day (SE of difference (SED) 34; P < 0.01) and protein (excluding wool) gain were 27, 32, 44, 45, 41 and 39 g/d (SED 4; P < 0.001) for feeds L, A, B, C, H and U respectively. When sheep were given a choice between a feed below (L or A) and a feed above their CP requirements (H; as judged by the single-feeding treatments) the CP concentration selected was not different between the two pairs: 131 (SE 4) v. 133 (SE 4) g CP/kg feed for pairs LH and AH respectively. On the choices BH and CH (a choice between two feeds above requirements) the feed lower in CP was constantly preferred (874 (SE 33) and 910 (SE 33) g feed B and C respectively per kg total feed intake; CP selected was 157 and 178 g CP/kg respectively). However, this was not the case with the UH choice on which sheep consumed only 599 (SE 61) g feed U/kg total feed intake, resulting in a selection of a higher CP in their diet (173 g CP/kg). The live-weight gains of the animals given a choice between two feeds were 416, 387, 415, 410 and 383 g/d (SED 37) and protein gains were 45, 40, 46, 50 and 43 (SE 7) for pairs LH, AH, BH, CH and UH respectively, which were comparable with the best performance achieved on a single feed. The results suggest that sheep were able to select a diet that meets their CP requirements and avoid, at least to a certain extent, excess of protein intake. It is also possible that sheep discriminate against a property of feed U, such as an excess of urea, when this feed is paired with a feed high in CP.


1983 ◽  
Vol 36 (1) ◽  
pp. 7-19 ◽  
Author(s):  
P. T. Kendall ◽  
M. J. Ducker ◽  
R. G. Hemingway

ABSTRACTIndividual dry matter intakes were measured using four groups of 16 ewes, indoors or at sparse winter grazing. In periods of varying duration (14 to 35 days) the ewe groups received 14 feedblock supplements competitively, eight trough supplements competitively or two feedblock supplements individually. In each period hay was available ad libitum. All supplements contained chromic oxide and individual supplement intakes were estimated by total faecal collection. Individual hay and total dry-matter intakes were estimated by faecal apportionment according to indigestibility of dietary components.Metabolizable energy content (0·81 × digestible energy) of the feedblocks ranged from 7·9 to 9·2 MJ/kg dry matter compared with a value of 13·0 MJ metabolizable energy/kg dry matter for concentrates. The variation in individual supplement intake was large, irrespective of type of supplement. However the mean coefficient of intake variation for 14 feedblock supplements (0·56) significantly (P < 0·05) exceeded that (0·39) for eight trough supplements at equivalent mean dry-matter intakes.Thus, ‘free-access’ feedblocks did not allow a more uniform supplementation than trough supplements. Supplement intake variation was higher outdoors and increased as total feedblock intake reduced.The variation in individual hay and total dry-matter intake was lower, and generally independent of that for the supplements. Mean coefficient of variation of 0·24 and 0·22 were obtained for hay and total dry matter, respectively, based on 22 collections with competitively fed sheep.Total daily metabolizable energy intakes of individual ewes outdoors ranged from 5 to 22 MJ per collection.


1987 ◽  
Vol 109 (2) ◽  
pp. 337-343 ◽  
Author(s):  
R. H. Phipps ◽  
J. D. Sutton ◽  
R. F. Weller ◽  
J. A. Bines

SummaryNinety-nine lactating British Friesian cows, in their second and subsequent lactations, were divided into two groups receiving ad libitum grass silage. The cows in group A were offered silage individually through Calan Broadbent gates while those in group B were given 24 h/day access to a self-feed silage clamp. The crude protein (CP), acid-detergent fibre (ADF), neutral-detergent fibre (NDF), in vitro digestible organic matter and estimated metabolizable energy (ME) values in the D.M. of the silage were 140, 373, 584, 610g/kg D.M. and 9·7 MJ/kg D.M. respectively. The cows in each group received either 11kg/day fresh weight of concentrate S in which the principal energy source was cereal starch or 9 kg/day fresh weight of concentrate F containing mixed high quality fibre sources plus 2 kg/day fresh weight of concentrate S. The CP, ADF, NDF, starch and sugar concentrations in concentrates S and F were 203, 71, 204, 444, and 44 and 202, 147, 329, 116 and 149g/kg D.M., respectively.The only significant difference produced by method of silage allocation was that groupfed cows gained more live weight (P < 0·01) than those fed individually.Over the whole experimental period the mean silage D.M. intake of cows fed concentrate F in group A was 0–5 kg/day higher than those fed concentrate S. However, in early lactation the benefit to silage intake in favour of concentrate F was 1 kg D.M./day.In group A estimated intakes derived from calculated ME inputs and outputs were markedly lower than the observed intakes, but were similar to correspondingly derived estimates for group B.Although concentrate type did not affect milk yield, concentrate F was associated with a higher fat concentration and yield (P &lt;0–05) but a lower protein concentration (P &lt; 0·001) and a slightly lower yield.The in vivo digestibility coefficients for D.M. and organic matter determined in lactating dairy cows given concentrates S and F respectively were similar (0·724 v. 0·716 and 0·749 v. 0·742) but that for ADF was significantly (P < 0·001) higher (0·565 v. 0·673) in the ration containing concentrate F than in that containing concentrate S.Estimates of the mean efficiency of utilization of the production ME made on a weekly basis were unaffected by concentrate type.


1975 ◽  
Vol 15 (77) ◽  
pp. 773 ◽  
Author(s):  
N Guirguis

The metabolizable energy values (ME) of 16 feed ingredients available in Australia were determined with broiler chicks of both sexes. The chickens were fed test diets in which the feed ingredients replaced dextrose in a basal diet. The mean coefficient of variation was low in each determination of ME (range 0.78 to 1.20, mean 0.94 per cent). Sex had no significant effect on the ME value of most feedstuffs with the exception of oats, where ME values were significantly higher for female than for male chicks (P < 0.05). The ME values calculated from the chemical composition of feed ingredients by means of the equations of Sibbald et al; Carpenter and Clegg; and Bolton were considerably higher than that obtained by chick assay. On the other hand ME values of cereals predicted by means of Titus's equation were similar to those obtained in this experiment and to biologically determined values of ME published in the literature. ME values of protein concentrates varied considerably when estimated either by chick assay or by chemical composition. Titus's prediction equation was considered to provide a reasonably accurate estimate of the ME value of a ration where information is available only of the chemical composition of the feed ingredients.


1977 ◽  
Vol 88 (3) ◽  
pp. 539-552 ◽  
Author(s):  
J. J. Robinson ◽  
I. McDonald ◽  
C. Fraser ◽  
R. M. J. Crofts

SUMMARYSeventy-nine Finnish Landrace x Dorset Horn ewes in lamb to Suffolk rams were used in a comparative slaughter experiment to assess the effects of numbers of foetuses on the growth of the products of conception. The mean number of foetuses was 2·7, with a range from 1 to 5. The ewes were individually penned and given a standard diet with metabolizable energy concentration 7·7 MJ/kg and N concentration 21 g/kg, rationed at 2 kg/day during the first month and 1·25 kg/day during the second and third. Allowances beyond that time were on two scales and depended on the number of foetuses being carried as diagnosed by radiography. The ewes were slaughtered between 50 and 145 days of gestation. The gravid uterus was dissected into foetal, placental, foetal fluid and empty uterus components. Equations were fitted to the weights of each component to describe the effects of stage of gestation, litter size and ewe weight. For the mean weight per foetus (Y, kg) the preferred equation isIn (Y)= 2·419–17·574e-0.01976t–00079ft+0–0046w,where tis the time in days from conception, / is the number of foetuses and wis the weight (kg) of the ewe at mating. This is a version of the Gompertz equation, with additional terms to express the effects of / and w.The weights of the placenta and of the empty uterus were similarly fitted by versions of the Gompertz equation but the mean weight of fluids per foetus (Z, kg) or, rather, its natural logarithm was best described by a third degree polynomial, which isIn(Z) = –11·518 + 0–326t;–0·00316t2+0·0000102t3.None of the weights was significantly affected by the level of feeding in late pregnancy.Estimates of mean weights from the equations and of daily rates of gain in weight from the first differentials of the equations are tabulated against stage of gestation and litter size, and the forms of the weight, growth rate and specific growth-rate curves are illustrated graphically.The equation for foetal weight estimates that at the end of pregnancy the mean weight per foetus is reduced by a factor of 0–89 for each additional foetus being carried. The mathematical model implies that the differences originate in early pregnancy, when the factor is very close to unity, and that the mean weights gradually diverge. In the absence of direct evidence this would appear to be the simplest hypothesis, rather than the assumption in most of the earlier literature that the effect is entirely confined to the last 4 or 5 weeks of gestation.Just before parturition the total daily weight gain of quadruplet foetuses was about 250 g and was associated with a similar gain in weight of foetal fluids, the ratio of fluid weight to foetal weight appearing to increase with litter size. The ewes were clearly under considerable physical stress. It is suggested that this aspect must be closely considered when greater prolificacy is sought.


Insects ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 23 ◽  
Author(s):  
Ana M. Barbosa-Silva ◽  
Alexandre Vasconcellos

Wood is the main dietary item for most termites; however, supplementation with certain nutrients may occur via the ingestion of other available food resources in the ecosystem. The objective of this study was to evaluate the consumption of lichens with different C, N, and P contents by Constrictotermes cyphergaster under laboratory conditions, and estimate the intake of this substrate by this species in a semi-arid area of Northeast Brazil. The foraging activities of fifteen field colonies were monitored over 15 days from 6:00 p.m. to 6:00 a.m., and the lichens that were consumed were identified. Blocks of lichen thallus (1.5 × 1.5 cm) of four lichen species were offered to the termites in the laboratory. The mean total consumption rate of lichen by C. cyphergaster was 0.032 mg lichen/g termite (fresh weight)/day. Dirinaria confluens was the lichen most consumed by termites (0.010 mg lichen/g of termite (fresh weight)/day), followed by Lecanora spp. and Haematomma persoonii at a mean consumption of 0.008 and 0.006 mg lichen/g termite (fresh weight)/day, respectively. Based on the size of the C. cyphergaster populations, the estimated lichen consumption rate was 105.12 g lichen/ha/year. Lichen consumption was significantly affected by the N content and the C:N and C:P ratios, with the N content being the factor that best explained the consumption by the termites. The results suggest that C. cyphergaster can use lichens as a supplemental source of nutrients, especially nutrients that are found in low concentrations in wood.


2010 ◽  
Vol 28 (No. 4) ◽  
pp. 298-308 ◽  
Author(s):  
J. Horníčková ◽  
R. Kubec ◽  
K. Cejpek ◽  
J. Velíšek ◽  
J. Ovesná ◽  
...  

The contents of major S-alk(en)ylcysteine sulfoxides (namely alliin, methiin and isoalliin) were determined in a set of 58 various garlic genotypes (22 flowering plant morphotypes, 14 semi bolting plants and 22 scape absent morphotype plants), representing the garlic collection of the Allium gene bank in the Czech Republic. The plants were cultivated in four successive years (2005&ndash;2008) and analysed immediately after harvest and subsequently after eight weeks of storage at 5&deg;C. The total content of the three cysteine derivatives in fresh samples varied considerably between 3.35 mg/g fresh weigh and 12.77 mg/g fresh weight, with the mean of 7.50 mg/g fresh weight and the average relative proportions of alliin/methiin/isoalliin of 83/16/1. Upon 8-week storage at 5&deg;C, the average total amount of S-alk(en)ylcysteine sulfoxides increased by 30% to 9.75 mg/g fresh weight, with the alliin/methiin/isoalliin ratio changing to 82/14/4. The data obtained were statistically evaluated using linear discrimination analysis to distinguish the differences between the years of harvest, between freshly harvested and stored samples, and between the individual morphotypes. While the year-to-year differences between the samples were statistically not very significant, the fresh and stored samples as well as the individual garlic morphotypes differed considerably in S-alk(en)ylcysteine sulfoxide content. Our results indicate that the content of S-alk(en)ylcysteine sulfoxides primarily depends on various genetic factors and post-harvest storage conditions, whereas the climatic conditions during the growth (e.g. temperature, irrigation) influence their level to a lesser extent. Various implications for the food and pharmaceutical industries are discussed. &nbsp;


1987 ◽  
Vol 58 (3) ◽  
pp. 453-461 ◽  
Author(s):  
John W. Hilton ◽  
James L. Atkinson ◽  
Stanley J. Slinger

1. Quadruplicate groups of rainbow trout (Sulmo gairdneri) (mean body-weight 24.9 g) were reared on six dietary treatments (practical-type diets) in a modified paired-feeding experiment for 12 weeks at 15° to determine the net energy (NE) value of starch and glucose to rainbow trout.2. Three test diets were prepared to contain (g/kg): 0 supplemented carbohydrate (diet 1), 250 maize starch (diet 2) and 250 glucose (diet 3) and were givenad lib.to the trout with the feeding rate of the glucose- and starchfed groups being monitored after each feeding. The remaining three treatments involved controlled feeding of the trout with diet 1 at 75% of the feed intake of trout reared on diets 2 and 3, so as to provide the same levels of protein and lipids without carbohydrate, and with diet 2 at 100% of the feed intake of trout reared on diet 3.3. The difference in the final carcass energy of thead lib.-fed group and the respective controlled-fed group divided by the amount of dietary glucose or starch energy consumed by the trout is the NE value for that carbohydrate.4. The determined NE value of glucose was 3.99 kJ/g and starch 2.17 kJ/g, which is 24.6 and 12.6% respectively of the gross energy values of these carbohydrates in rainbow trout.5. The results indicate that digestible energy and calculated metabolizable energy values for carbohydrates in rainbow trout overestimate the utilizable energy content of the diet.6. The determined NE values for glucose and starch in the present study should be used with caution since various factors (such as the feeding rate determined in the present study) may affect the utilization of dietary carbohydrates in rainbow trout.


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