The effects of dietary nitrogen sources and levels on rumen fermentation, nutrient degradation and digestion and rumen microbial activity by wether sheep given a high level of molasses

1996 ◽  
Vol 63 (1) ◽  
pp. 123-131 ◽  
Author(s):  
T. Yan ◽  
N. W. Offer ◽  
D. J. Roberts

AbstractA 4 × 4 Latin square design experiment with 3-week experimental periods was conducted with four wether sheep, each fitted with a permanent rumen cannula, to evaluate the effects of dietary protein sources and levels on fermentation and microbial activity in the rumen. Four complete diets were offered each containing (g/kg dry matter (DM)) molasses 248, grass silage 200 and barley straw 260. The control diet (C) also contained barley and soya-bean meal and the other three diets were supplemented with urea (CU), soya-bean meal (CS), and soya-bean meal and fish meal (CSF), respectively. This gave foods of similar concentrations of metabolizable energy (ME) and estimated fermentable ME (10·6 and 9·8 MJ/kg DM, respectively), but different levels (g/kg DM) of estimated effective rumen degraded dietary protein (ERDP) and digestible undegraded protein (DUP) (ERDP/DUP, 84/17, 109/17, 116/38 and 119/54 for diets C, CU, CS and CSF, respectively).No clinical symptoms of ill health in the animals due to the feeding of molasses were observed during the experiment. The average pH values of rumen liquors obtained at various sampling times post feeding for diets C, CU, CS and CSF were 6·40, 6·49, 6·62 and 6·47 (s.e.d. 0·06 P < 0·05) respectively and average ammonia-nitrogen concentrations were 63, 81, 90 and 113 mg/l (s.e.d. 14·9, P < 0·02) respectively. The average concentrations of total volatile fatty acids in the rumen liquor were similar across the four treatments. The molar proportions of propionate and butyrate were higher for the diet C than for the other three diets (P < 0·05), while acetate was lower (P < 0·05). Supplementing with true protein (P < 0·05), but not with urea (P > 0·05), increased the molar proportions of isobutyrate and isovalerate. Whole tract apparent digestibilities of DM and organic matter did not differ significantly across the four treatments, but neutral-detergent fibre apparent digestibility (0·677, 0·672, 0·716 and 0·728 (s.e.d. 0·017) g/kg DM for diets C, CU, CS and CSF respectively) and the proportions of hay DM that disappeared in the rumen during 24 h incubation (0·223, 0·238, 0·284 and 0·271 (s.e.d. 0·019) g/kg DM) were significantly lower for diets C and CU than CS and CSF (P < 0·05). Urinary excretion of purine derivative nitrogen was similar across the four treatments. The results obtained from the present study indicate that there were no significant differences in the microbial crude protein synthesis in the rumen when a diet containing molasses was supplemented with urea or true protein. However, the supplementation of this control diet with true protein, but not with urea, did stimulate the degradation of hay DM in the rumen and the digestion of dietary fibre in the whole tract.

1986 ◽  
Vol 43 (2) ◽  
pp. 201-209 ◽  
Author(s):  
J. P. Alawa ◽  
G. Fishwick ◽  
J. J. Parkins ◽  
R. G. Hemingway ◽  
T. C. Aitchison

ABSTRACTThree experiments, designed as three simultaneous 4 × 4 Latin squares (21-day feeding periods), were conducted using pregnant beef cows. Diets were based on barley straw given ad libitum together with 1·7 kg dry matter (DM) of either molassed sugar-beet pulp (MSBP) (experiment 1), unmolassed sugarbeet pulp (USBP) (experiment 2), or rolled barley (BARLEY) (experiment 3). In the respective experiments, MSBP, USBP and BARLEY were given either alone, to provide about 200 g crude protein (CP) per day (CONTROL) or were supplemented with urea (U), untreated soya-bean meal (SBM) or formaldehyde-treated soya-bean meal (FT-SBM) to provide a further 200 g CP per day. The contrasting dietary treatments in the three experiments provided intakes of rumen-degradable protein (RDP) ranging from 16 to 388 g/day.All protein supplements improved overall straw DM intakes, the improvement being significant for U only (P < 0·01). A linear relationship between the daily intake of RDP (g) and straw DM (kg) was obtained. The regression equation was:DM intake = 5·03 + 0·0035 × RDP (R2 = 0·703; residual s.d. 0·561; d.f. 35; P < 0·001).All protein supplements also improved the apparent digestibility of straw organic matter (OM) (P < 0·05) and the metabolizable energy (ME) obtained from straw (P < 0·01). Blood urea was increased due to supplementation with urea (P < 0·001), SBM (P < 0·01) and FT-SBM (P < 0·05). Supplementation with BARLEY appeared to improve straw DM intake over MSBP and USBP but this was not reflected in improved ME intake from straw.


1988 ◽  
Vol 47 (2) ◽  
pp. 283-289 ◽  
Author(s):  
Isobel C. Vincent ◽  
H. Ll. Williams ◽  
R. Hill

ABSTRACTThree types of high glucosinolate British rapeseed meal (RSM) — extracted, expeller and extruded — were incorporated in ewe diets at 200 g/kg; soya-bean meal (SBM) at 165 g/kg replaced RSM in a control diet. Eighty housed Suffolk-Mule ewes were divided into four equal groups and given one of four diets, A (control SBM), B (extracted RSM), C (expeller RSM) or D (extruded RSM) for one reproductive cycle. Diets A and B were compared for a second season. The ewes were given a maximum of 2·5 kg diet per day during lactation. Barley straw was available ad libitum. The ewes were mated in November and December. Lambs were weaned at 42 days of age; they were given creep food similar in composition to their dams' lactation diets.There were no dietary effects on ewes in overall health, live weight, oestrous activity, conception, number of lambs born alive or lamb birth weights. A mean of 1·6 lambs were weaned per ewe mated and 58% of these were twins, in year 1. In year 2, 1·8 lambs were reared and 79% were twins. The mean milk yield over the first 4 weeks of lactation was 3·2 1 and there were no significant dietary effects. Fat concentration in milk was very variable, but in general was slightly depressed by the RSM diets, significantly so at three sampling dates. Protein concentration was consistently lower in milk from RSM than SBM groups, significantly lower at four of the weekly samplings. Thiocyanate levels in plasma and milk were related to glucosinolate intake, but were not associated with any detrimental effects. At all sampling dates, values for RSM groups were significantly greater than for SBM ewes. Plasma thyroxine values were similar regardless of diet


1988 ◽  
Vol 47 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Isobel C. Vincent ◽  
R. Hill ◽  
H. Ll. Williams

AbstractThe response of Hereford × Friesian heifers to large intakes of two types of high glucosinolate rapeseed meal were studied during two 5-month periods in consecutive years. In year 1, six heifers were given a compound concentrate food containing 250 g/kg extracted rapeseed meal and six control animals were given concentrate containing 210 g/kg soya-bean meal. In year 2, a further six heifers were given concentrate containing 320 g/kg expeller rapeseed meal and six control animals were given the same soya-bean meal compound concentrate. The crude protein (CP): metabolizable energy (ME) ratio of all diets was 14·3 g CP per MJ ME. Barley straw was the only roughage offered.There were no differences between groups in ovarian activity assessed from plasma progesterone concentrations, nor in behavioural activity around oestrus. The heifers were slaughtered 6 weeks after artificial insemination. Pregnancy rate was proportionally 0·58 (7/12) in the rape-fed and 0·67 (8/12) in the control heifers (P > 0·05). Foetuses from heifers given rapeseed meal were slightly smaller than those from control heifers; the difference was significant in year 2 (P < 0·05).Thyroid glands of heifers given rapeseed meal showed histological evidence of goitrogenicity but weights of the glands did not reflect this. Plasma thyroxine values were depressed in heifers given rapeseed meal (year 1, P < 0·001; year 2, P < 0·05). Plasma thiocyanate was elevated in rapeseed meal heifers in both years (P < 0·001) compared with values for control animals.


1975 ◽  
Vol 34 (3) ◽  
pp. 363-373 ◽  
Author(s):  
E. Wetnli ◽  
T. R. Morris ◽  
T. P. Shresta

1. Three growth trials were done using male broiler chicks. In the first two trials, groundnut meal was used, with and without supplementary methionine and lysine. In the third trial, soya-bean meal was used with and without supplementary methionine. Protein levels ranged in the first trial from 120 to 420 g/kg diet and in the third trial from 120 to 300 g/kg diet. Thus the assumed minimal amino acid requirements of the chick were supplied by high levels of low-quality dietary protein.2. Diets based on cereals and groundnut meal did not support maximum live-weight gain or maximum efficiency of food utilization at any level of dietary protein. When the principal deficiencies of lysine and methionine were corrected, this protein mixture was capable of supporting the same growth rate as a control diet of cereals and herring meal.3. Diets based on maize and soya-bean meal did not support quite the same growth rate as similar diets supplemented with methionine, even though the protein level in the unsupplemented diets was sufficient to meet the assumed methionine requirements.4. These results are interpreted as examples of amino acid imbalance in diets composed of familiar feeding-stuffs. It is concluded that one cannot assume that the poor quality of a protein source can always be offset by increasing the concentration of dietary protein.


1988 ◽  
Vol 46 (2) ◽  
pp. 249-255 ◽  
Author(s):  
M. Hadjipanayiotou ◽  
E. Georghiades ◽  
A. Koumas

AbstractTwo trials, one with 36 twin-suckling Chios ewes and the other with 32 twin-suckling Damascus goats, were conducted to study the effect of protein source (fish meal v. soya-bean meal) on the pre-weaning milk yield of the dams, and the growth performance of their offspring. The control (C) concentrate mixture was similar in both trials, using soya-bean meal (SBM) (195 kg/t) as a source of supplemental protein. In the experimental diet (FME) of the ewe trial, SBM was replaced completely by fish meal (FM) whereas in the goat trial (FMG) 83 kg of SBM were replaced by 50 kg FM. Dry matter (DM) and crude protein (CP) degradation of the three isonitrogenous mixtures were measured using nylon bags incubated in the rumens (2, 6, 16, 24 and 32 h) of three Damascus goats. There were no significant differences between mixtures for DM and CP effective degradability at 005 per h outflow rate. At 0·08 per h outflow rate however, lower degradability values were obtained with the FME than with the C diet. There were differences in the effective CP degradability of SBM and FM used in the ewe trial, but the FM used in the goat trial was of higher CP degradability and similar to that of SBM. Ewes on FM produced more milk than those on the control diet (C 3·44 v. FME 3·84 kg/day), whereas milk yield of goats was similar in the two treatments (C 3·87 v. FMG 3·82 kg/day). There were no differences between treatments for ewe milk fat (C 44 v. FME 43 g/kg) or protein concentration (C 54 v. FME 53 g/kg). Goats on fish meal (FMG) produced milk of higher protein (C 37 v. FMG 40 g/kg), but of similar fat (C 42 v. FMG 43 g/kg) concentration to those on the SBM (C) diet. With the exception of the better conversion (milk: gain ratio) efficiency (C 5·17 v. FME 4·44) of male lambs sucking ewes on the FM diet, no other differences were observed in the performance of lambs or kids. Lambs consumed less milk than kids (lambs: males 4·69, females 5·13; kids: males 6·63, females 6·98) per unit of weight gain.


Author(s):  
J S Blake ◽  
T D A Brigstocke ◽  
P J Kenyon

Reduction of the financial support by the EC to sheep farmers has highlighted the need for lamb fattening diets which can adjust the rate of lamb growth, depending on market needs. A trial was run at BOCM SILCOCK Development Unit, Barhill using 144 Texel and Suffolk x Mule lambs, with a mean start weight of 18.6 ± 0.50 kg (mean ± SE). Lambs were divided into 24 pens and allocated one of four compound diets (Diets A, B, C or D). The diets were designed to be isoenergetic with an estimated energy of 11.4 MJ ME/kg DM and contained 138, 172, 206 and 250 g crude protein/kg DM. Protein levels were increased by increasing soya bean meal inclusion from 0 to 25% and reducing barley and wheat levels.Formulations and actual analysis are shown in Table 1. Lambs were bedded on barley straw refreshed daily, with compound diets and water available ad-lib.


Author(s):  
M. Ellis ◽  
D.S. Parker

Synthetic lysine and fat supplements are widely used in diets for growing pigs. However, there is evidence to suggest that free lysine is more rapidly absorbed than protein bound amino acids resulting in reduced growth performance particularly under infrequent feeding regimes. In addition, the incorporation of conventional fat supplements into cereal based diets is problematic particularly where on-farm mixing of feed is carried out. One potential solution to both these problems is to use fat coated synthetic lysine sources which have recently become available and two such materials were evaluated in this study.Four dietary treatments were compared. These were a control diet (C) with soya bean meal as the protein supplement and diets in which 0.3 of the total lysine was supplied from either synthetic lysine (S) or synthetic lysine coated with a single (SC) or a double layer(DC) of hardened soya oil. All diets were barley based and were formulated to contain the same level of total lysine (0.01) and hardened soya oil.


1985 ◽  
Vol 53 (1) ◽  
pp. 137-147 ◽  
Author(s):  
Jane Leibholz

1.Forty pigs between 23 and 51 d of age were given ad lib. diets containing wheat and one of five protein concentrates: meat meal A, meat meal B, soya-bean meal, milk and lupins (Lupinus augustifolius). Twenty of these pigs were given indigestible markers from 51 to 56 d of age and were killed at 56 d of age.2.The diets containing meat meals A and B, soya-bean meal and milk contained 2.3 g total methionine/kg and the diet containing lupins contained 2.1 g/kg.3.A further forty pigs of the same age were given the same diets supplemented with 1 g synthetic methionine/kg.4.The weight gains and feed conversion ratios of the pigs given the diets containing 2.1–2.3 g methionine and 3.1–3.3 g methionine/kg were not significantly different.5. The weight gains of the pigs given lupins (2.1 g methionine/kg) were less than those of the pigs given the diets containing 2.3 g methionine/kg.6. The apparent digestibility of dry matter (DM) and nitrogen was less for the diets containing the meat meals (0.75 and 0.78 respectively) than for those containing the other protein concentrates (0.80 and 0.84).7.The retention times in the large intestine of the diets containing soya-bean meal and lupins were 965 and 1083 min which were greater than those of the diets containing the other protein concentrates, mean 732 min.8. The major site of N digestion and absorption for the diet containing milk was the area of the small intestine 25–50% of total length from the pylorus, while for the other protein concentrates the major site was 50–75% of its total length from the pylorus.9. The digestion and absorption of N in the large intestine was less (3.4%) for the diet containing milk than for those containing the other protein concentrates (7.5–11.3%).10. The apparent digestibility of the methionine to the ileum for the five diets ranged from 0.74 to 0.86 while the calculated retention of the apparently-absorbed methionine was 1.00. It was suggested that methionine digestibility could be used as an indicator of availability.11. The calculated retention of apparently absorbed N in the carcass was 0.71 for the pigs given the diet containing milk and 0.51–0.58 for the pigs given the other diets.


2002 ◽  
Vol 75 (3) ◽  
pp. 415-426 ◽  
Author(s):  
I. Fernández-Fígares ◽  
R. Nieto ◽  
the late C. Prieto ◽  
J. F. Aguilera

AbstractAn experiment was carried out in growing chickens to study the effect of supplementation of a semi-synthetic diet containing soya-bean meal as the sole protein source with DL-methionine, to improve its biological value, on the excretion of endogenous protein and amino acids measured in lower ileum and total tract using traditional methods. Thirty-two White Rock male broilers (10 days old) were randomly divided into eight groups each of four birds, of similar body weight (mean live weight: 142·8 (s.e. 0·68) g), and individually housed in metabolism cages. Following a paired-feeding design based on metabolic body weight (kgM0·75), each group of birds was given, for an experimental period of 20 days, each of four levels of protein (60, 120, 180 or 240 g/kg; 5 days each) in two groups of isoenergetic (14·5 kJ metabolizable energy per g dry matter) and semi-synthetic diets based on soya-bean meal, either not supplemented or supplemented with 2 g/kg DL-methionine (diets S and SM, respectively). After 3 days of each treatment excreta were collected for 48 h, frozen and stored at –20ºC. At the end of the fourth treatment three chickens of each group were killed and their lower ileal contents collected. The remaining chick of each treatment was fasted for 24 h and given a protein-free diet for 8 days and excreta were collected for the last 4 days. Then (day 39 of age), chickens were killed and lower ileum contents removed and stored at –20ºC. Samples of excreta and lower ileum contents were subjected to nitrogen (N) analysis by Kjeldahl procedure and amino acid (AA) analysis by high-performance liquid chromatography. Supplementation with DL-methionine of the soya-bean meal-based diets halved total tract endogenous AA losses. Regression analysis produced a higher estimation of ileal and faecal endogenous AA excretion than feeding a protein-free diet. Endogenous AA excretion determined in the lower ileum was higher than in excreta no matter which estimation procedure was utilized. In conclusion, supplementation of dietary protein with the first limiting AA to improve its protein quality, causes an important drop in endogenous AA losses, that may have an important effect on the N economy and energy requirements in poultry. The use of regression analysis on excreta data where graded amounts of protein are given to growing chickens, seems a suitable method for determining endogenous AA losses provided that good quality proteins are used.


1991 ◽  
Vol 52 (3) ◽  
pp. 465-475 ◽  
Author(s):  
R. W. J. Steen

ABSTRACTTwo experiments have been carried out to examine the effects of the level of protein supplementation given with grass silage-based diets on the performance and carcass composition of bulls, and to compare diets based on silage and dried forage. The five treatments used consisted of grass silage offered ad libitum and supplemented with 2·5 kg dry matter (DM) of barley-based concentrates containing (1) zero (2) 200 (3) 400 and (4) 600 g soya-bean meal per kg and (5) artificially dried grass and hay supplemented with 3·2 kg concentrate DM. The silages used in both experiments were well preserved, containing on average 200 g DM per kg; 140 g crude protein (CP) per kg DM; 63 g ammonia-nitrogen per kg total N and 731 g digestible organic matter per kg DM. The bulls were of late-maturing breed type and were initially 12 months old and 412 and 405 kg live weight in experiments 1 and 2 respectively. For treatments 1, 2, 4 and 5 in experiment 1 respectively (treatment 3 was not used) total DM intakes were 8·3, 8·3, 81 and 110 (s.e. 0·21) kg/day; CP intakes 1063, 1271, 1664 and 1539g/day; metabolizable energy intakes (MEI) 98, 99, 96 and 87 MJ/day; carcass weights 317, 316, 317 and 316 (s.e. 3·2) kg; carcass saleable meat concentrations 714, 712, 718 and 716 (s.e. 5·8) g/kg and carcass fat trims 73, 81, 73 and 68 (s.e. 3·9) g/kg. In experiment 2 for treatments 1 to 5 respectively total DM intakes were 8·3, 8·5, 8·3, 8·4 and 11·2 (s.e. 0·26) kg/day; CP intakes were 1090, 1329, 1504, 1720 and 1561 g/day; MEI 102, 106, 103, 103 and 94 MJ/day; carcass weights 318, 331, 330, 327 and 321 (s.e. 3·3) kg; carcass saleable meat concentrations 726, 721, 725, 721 and 732 (s.e. 60) g/kg and fat trims 71, 77, 78, 80 and 64 (s.e. 4·5) g/kg. It is concluded that protein supplementation of a silage-based diet did not affect performance or carcass fatness in experiment 1 or carcass fatness in experiment 2, but including 200 or 400 g soya-bean meal per kg concentrate increased performance in experiment 2. Animals given silage produced fatter carcasses than those given dried forage in experiment 2 but not in experiment 1.


Sign in / Sign up

Export Citation Format

Share Document