High-protein Supplement Research Articles

INFLUENCE OF POPULATION DENSITY AND HYBRID MATURITY ON PRODUCTIVITY AND QUALITY OF FORAGE MAIZE

Nine maize hybrids, representing early, medium and late maturities (maximum 3000 corn heat units), were grown at 75 000 and 100 000 plants/ha for 2 yr at two locations in order to examine the in vitro digestible dry matter (DDM) yield and quality of whole-plant (shoot) and stover components. Early hybrids produced 90% as much DDM yield as medium or late hybrids. Comparing densities, the higher density resulted in a greater increase in DDM yield at Surrey than at Agassiz and it did not depress whole-plant dry matter (DM) content. Whole-plant DM digestibility (DMD) was 2% lower for early hybrids compared to mediums or lates. Density had no influence on whole-plant DMD at Surrey, but the higher density reduced it by 1% at Agassiz. Stover DDM yield was greater at Surrey than at Agassiz whereas whole-plant DDM yield was greater at Agassiz. Harvest index was positively, but not closely, correlated with whole-plant DMD (r = 0.28***) and was inversely correlated with stover DMD (r = − 0.45***). Thus, nutritive value of maize was only marginally dependent on the grain component. Results suggest that, in the marginal corn-growing environments of the region studied, it may be beneficial to use hybrids considerably later than those normally adapted and grow them at a density approaching 100 000 plants/ha to maximize digestible yields and quality. The harvested forage may have a DM content too low for direct ensiling, but this can be rectified by addition of dry high-protein supplements (e.g. alfalfa cubes) at ensiling time.

A note on supplemental protein and monensin for steers wintered on dormant native range

ABSTRACTNinety-six Hereford steer calves that weighed 249(s.e.4·7)kg were allocated randomly to four treatments of 24 steers each in a randomized complete block design with four blocks. The steers grazed dormant native range forage that contained 41 to 60 g of crude protein per kg dry matter during the 120-day wintering trial and were given 0·91 kg of supplement per head per day. The supplements used contained 175 or 350 g crude protein per kg dry matter and 0 or 165 mg monensin per kg supplement; a factorial arrangement of treatments was used in allocating the supplements. Weight gains of steers given the high-protein supplements were greater than those on the low-protein supplements during periods 1(0 to 61 days) and 2 (62 to 120 days), and over the total trial (P < 0·01). Monensin increased weight gains during period 1 and the total trial (P < 0·01). The protein level × monensin interaction was not significant for either period or the total trial (P > 0·15). The results indicate that inclusion of monensin in protein supplements for growing cattle grazed on low-quality dormant native forage may allow some reduction in protein content of the supplement.

Diet in Pregnancy: A Randomized Controlled Trial of Nutritional Supplements

This is a detailed description of the methodology and collection of data, as well as an elaboration of the conclusions, performed by the authors in their controversial article "A Randomized Controlled Trial of Prenatal Nutritional Supplementation in New York City" (<i>Pediatrics</i>1980;65:683-697). Starting with approximately 800 mothers who were expected to have been deprived of protein, the authors gave to one third a protein supplement, to one third a balanced protein-calorie supplement, and to one third routine clinical care. After recruitment of the study groups, it was found that the nutritional deficiency most likely to be present was one of calories rather than protein. The high-protein supplement seemed to have an adverse effect on the outcome of some pregnancies, despite increased maternal weight gain. Some psychological effects at 1 year of age may have been produced by the high-protein supplement during pregnancy. This study is bound to be quoted frequently

Questioning Conclusions on Prenatal Nutritional Supplementation

Rush, Stein, and Susser1 tell us that pregnant women receiving a high protein supplement were more likely to deliver prematurely than those receiving a complement (balanced calories and protein). Furthermore, they claim that these premature babies were significantly lower in birth weight than the premature babies of the complement and control groups. However, there was no statistically greater incidence of premature births in the supplement group than in the other two groups combined, nor were there significantly more perinatal deaths.

Protein quality and the cost of selected commercial protein supplements

The biologic value and the cost of three commercial protein supplements were compared using casein as the control. Each product was fed to rats as the sole protein source supplying 10 percent of the energy in a semipurified diet. Nonfat dry milk was equal to casein in PER, but the PERs of low-fat soy powder and high-protein supplement were significantly lower than the PER of casein. Nitrogen balance was positive for all protein supplements, but low-fat soy powder was significantly lower than the others. cost comparison per gram of protein showed low-fat soy powder to be the least expensive, nonfat dry milk to be slightly higher in cost, and the high-protein supplement to be the most expensive.

Protein studies on maize silage as a basal ration for dairy cows

SUMMARYIn Expt 1 40 lactating British Friesians, 20 cows and 20 heifers, were used to study the effect of crude protein (CP) content of the whole ration on milk yield, milk composition and live-weight change when maize silage was fed as the basal ration. There were four treatments with five cows and five heifers on each. During lactation weeks 4–12 the cows on treatments 1, 2, 3 and 4 all received 7 kg maize silage dry matter (D.m.) plus 8 kg D.m./day of a concentrate containing either 14, 18, 22 or 24% CP, respectively; heifers received 1 kg/day less of both silage and concentrate. This produced whole-ration CP contents of 11·7, 13·9, 16.·0 and 17·1%. In the subsequent lactation weeks 13–20 silage feeding was increased to 9 kg D.m./cow/day and concentrate feeding decreased to 5 kg D.m./cow/day. Heifers again received 1 kg/day less of both silage and concentrate. This decreased whole-ration CP contents to 10·5, 11·7, 12·9 and 13·4%.During lactation weeks 4–12 and 13–20, with the exception of milk fat content in weeks 13–20, there were significant linear effects of whole-ration CP content on milk yield, milk fat, protein, lactose and total solids. There were no significant curvilinear relationships. Thus, despite the fact that the highest numerical values were generally recorded for the animals on treatment 3, the results indicate that a whole-ration CP content of at least 17·1 and 13·4% are required in early and mid-lactation respectively.In Expt 2 the loss of D.m., acid-detergent fibre and nitrogen from maize silage suspended in nylon bags in the rumen was measured. Compared with feeding either a low or high protein supplement, losses were greater for silage fed alone. If it is accepted that nitrogen loss can be approximated to protein degradability, then the value for maize silage was between 0·6 and 0·7. Using the same technique in Expt 3, comparable nitrogen losses for fish meal, decorticated groundnut meal and soya-bean meal were 0·3, 0·9 and 0·9, respectively, after 24 h incubation.

A Randomized Controlled Trial of Prenatal Nutritional Supplementation in New York City

This randomized controlled trial of nutritional supplementation in pregnancy, in a poor black urban population in the United States, aimed to increase the birth weight and influence the postnatal development of the offspring of mothers at high risk of having low birth weight infants. The execution of the research design and adherence to the treatment regimen among the experimental population appeared adequate for a reasonable test of the treatments. At birth, the only significant favorable effect of supplementation observed was the prevention of depressed birth weight among the offspring of mothers who smoked heavily. With balanced protein-calorie supplementation, length of gestation was increased, the proportion of low-birth-weight infants reduced, and mean birth weight raised by 41 gm (not statistically significant). With high protein supplementation, there was an excess of very early premature births and associated neonatal deaths, and there was significant growth retardation up to 37 weeks of gestation. At 1 year of age, significant effects of high protein supplement were found on three psychological measures: visual habituation, visual dishabituation, and mean length of free play episodes. These measures were unrelated to measures of growth at birth and at 1 year of age. There were no detectable residual adverse effects of high protein supplementation at 1 year of age.

The response of spring-calving cows to a high level of protein in the supplement given with grass silage during early lactation

ABSTRACTA randomized block experiment, using 30 British Friesian cows, was used to assess the effects of offering supplements containing 172 and 234 g crude protein per kg dry matter in addition to grass silage which had a very high digestible organic matter in the dry matter of 769 g/kg. The animals, which had a mean calving date of 1 February, were blocked according to calving date and lactation number and allocated at random within each block to the two treatments. The treatments were applied from day 8 of lactation until the animals went to pasture on 13 April and both supplements were offered at the same rate of 7·6 kg per day. The total yields of milk produced during the experimental period were 1626 and 1650 ±38·4 kg and the mean daily yields during the final week were 24·8 and 25·6 ± 0·58kg for the medium and high protein supplements respectively. The mean live weights for the two groups were 524 and 544 ± 5·5 kg, and body condition score 2·9 and 3·3 ± 0·34 for the medium and high protein supplements respectively at the end of the treatment period. No significant treatment effects on milk composition were recorded at any stage during the experiment. Analysis of blood samples taken during the final week of the experiment showed plasma urea levels, at 220 and 290± 18 mg/1 for the medium and high protein supplements respectively, to be significantly different.

The effect of silage type on the performance of lactating cows and the response to, high levels of protein in the supplement

ABSTRACTA change-over design experiment, comprising four periods each of 4 weeks' duration, was used to evaluate three silage types each fed with two levels of protein in the supplement in a 3×2 factorial arrangement. The three silages were high digestibility unwilted (A), high digestibility wilted (B) and low digestibility unwilted (C). The supplements had crude protein contents of 152 and 240 g/kg dry matter, and were offered at a standard rate of 10 kg undried weight daily. The mean silage intakes were 9·3, 9·5 and 8·6 ±0·19 kg dry matter/day for A, B and C respectively, but protein content of the supplement had no significant effect on the intake of silage. Milk yield was significantly affected by both silage type and protein content of the supplement, with the mean yields being 23·6, 23·9 and 22·0 ± 0·49 kg/day for A, B and C respectively, and 22·4 and 24·0 ±0·40 kg/day for the medium and high protein supplements respectively. Although there was no significant interaction between silage type and protein content of the supplement, the greatest response to increased protein was obtained with B. Neither silage type nor protein content ofthe supplement affected animal live weight or milk composition (other than fat content, which was significantly affected by silage type). Blood plasma urea levels were 281 and 405 ± 28·0 mg/1 for the medium and high protein supplements respectively.Total ration digestibility and nitrogen balances were carried out on three animals per treatment. The digestibility of dry matter, organic matter and nitrogen was significantly affected by both silage type and level of protein in the supplement. The output of nitrogen in the urine was also significantly affected by both these factors.

Selection in Lupinus albus L. for lower seed manganese concentration

Seeds of 49 Mediterranean white lupin accessions and of 36 F5 families derived from 13 of them were analysed for manganese concentration. High concentrations in the range 1770–4640 µg g-1 dry matter were found in material grown near Canberra and lower ones (1060-2750 µg g-l) at Wagga Wagga, N.S.W. A small number of L. angustifolius L. lines grown under comparable conditions at both sites had 7- to 70-fold lower concentrations of manganese in their seeds than L. albus. The means for accessions and families of L. albus varied widely and continuously about the site means. High alkaloid lines had approximately two-thirds the manganese concentration of low alkaloid lines. Seeds from primary inflorescences had 6% lower manganese concentrations than those from higher order inflorescences. About one-quarter of the variation within the low alkaloid class was associated with seed yield variation, there being a negative correlation between these traits. There was no line x site interaction. Broad sense heritabilities at Canberra and Wagga Wagga were moderately high, so that selection for lower concentrations should be effective. The results suggest that selection for higher yield could be almost as effective as direct selection in reducing seed manganese concentration. The reduction should be sufficient to enable white lupin seeds, grown on soils no higher in available manganese than those used in this study at Canberra, to be safely used as a high protein supplement in pig and poultry rations. Selection for lower seed manganese should not affect seed calcium, phosphorus or protein concentrations, but would tend to increase seed yield and plant height at maturity.

Asbestos-Free Method for Determining Crude Fiber: Collaborative Study

Abstract A rapid asbestos-free method for crude fiber analysis has been tested collaboratively in 2 studies over the past 2 years. Nine laboratories participated in the 1976 study, which included 10 feed samples with crude fiber contents ranging from 2 to 33%, and 5 laboratories collaborated in the 1977 study on 6 high protein supplement samples, of highly gelatinous material, with crude fiber contents ranging from 0.5 to 12.0%. The combined results of the 2 studies showed the following for the AOAC and the asbestos-free methods, respectively: sd 0.55 and 0.49; sr (r = random error) 0.26 and 0.22; sb (b = bias) 0.48 and 0.43; average range between independent analyses 0.29 and 0.22% crude fiber; and average maximum spread among laboratories 1.7 and 1.4% crude fiber. The asbestos-free method is precise, accurate, and capable of filtering the proteinaceous, cellulosic, or starchy gels encountered in many samples, and eliminates the use of asbestos, thereby avoiding the hazards associated with inhalation of asbestos fibers. One chemist can easily complete 60 samples per day. The asbestos-free method has been adopted as official first action.

Time, Magnitude, and Quality Estimates of Forage Consumed by Deer in Woodland Clearings1

AbstractForages are seeded in woodland clearings by state and federal agencies to provide herbage for deer (Odocoileus virginianus). Such plantings can supplement the diet, but the quantitative and qualitative means by which agricultural forages supplement the food base are not known. The purpose of this study was to measure time and magnitude of use, and nutritional quality of a birdsfoot trefoil (Lotus corniculatus L.) — orchardgrass (Dactylis glomerata L.) mixture, a birdsfoot trefoil — bluegrass (Poa pratensis L.) — quackgrass (Agropyron repens (L.) Beauv.) mixture, and a mixture of native herbage (Danthonia spp., Festuca ovina L., Andropogon spp., Panicum spp., Rumex spp., Solidago spp., and Achillea millefolium L.) in order to establish guidelines for management of forage for deer in woodland clearings.Significant forage utilization occurred primarily in late April and May when only the grasses grown in association with birdsfoot trefoil were available. Annual consumption of these cool season grasses averaged 500 kg/ha or 8% of average annual production. The cool season grasses averaged 250%, crude protein during peak utilization. Significant utilization was not measured on the native herbage. Most of these species did not resume growth until after consumption of the cool season grasses declined.Management of forages for deer in woodland clearings should aim at producing forage during the early spring. Selected forages should be managed as a high protein supplement to bridge the gap between winter and summer foods. There appears to be little need to manage clearings as summer Led sources for deer.

Evaluation of Turkey Litter Silage as a Feed Source for Replacement Dairy Heifers

Record high grain and protein supplement prices in the early 1970s provided the impetus for developing lower priced substitutes for grains and concentrates in livestock rations. One promising substitute is animal wastes, since these are often of considerable nutritive value.The purpose of this paper is to evaluate the technical and economic feasibility of feeding ensiled turkey litter to replacement dairy heifers. In addition, the implications to both dairy and poultry producers of using turkey litter as a feed are also discussed.

Biochemical indices of nutrition reflecting ingestion of a high protein supplement in rural Guatemalan children

Biochemical indices of nutrition reflecting ingestion of a high protein supplement in rural Guatemalan children

Pros and cons of eliminating veld burning

Abstract Fire has been a factor of the environment in Africa since time immemorial and it is often caused by natural agencies such as lightning. It is maintained that there is much prejudice against veld burning, often ill‐founded. Fire has caused and maintained most of the world's grassland. When fire has been prevented plant succession has resulted in bush encroachment in the savanna and surrounding areas or in fynbos encroachment in others. Fire results in much old grass being wasted but, if this is not removed in some manner, the grazing deteriorates. Old grass can be removed by fire, mowing or grazing, using high protein supplements. The consequences of the different methods of removal, other than mowing, may be equally deleterious.

Dry season protein and energy supplements for beef cattle on native pastures at Katherine, N.T

Three experiments planned to gain information on the gross nutritive deficiencies of native pasture as a feed for beef cattle during the dry season were carried out at Katherine, N.T., between 1960 and 1962. Groups of local Shorthorn steers were grazed on native pasture from July to November and fed supplements of crushed sorghum grain and peanut meal at different levels of total digestible nutrients and digestible crude protein. The results suggest that up to the time of early storm rains, prior to the wet season proper, the dry standing native pasture is an adequate source of energy, which can be effectively utilized if cattle are given a small quantity of high-protein supplement. During the period of early rains, the pasture is not an adequate source of energy, and high-protein supplements do not prevent liveweight loss. High spring temperatures before the early rains did not appear to affect adversely the performance of supplemented cattle.

Effects of different protein contents in the rations of growing-fattening pigs

1. A co-ordinated trial has been carried out at eighteen centres to study the effects of feeding various quantities of high-protein supplement to growing-fattening pigs. In treatment 1, 10% white fish meal was included from weaning to 150 lb. live weight and 3% soya-bean meal was included from 150 lb. live weight to slaughter (approximately 210 lb.). Treatment 2 was the same as treatment 1 except that only 7% white fish meal was included during the first stage. Treatment 3 was the same as treatment 2 except that the rations were changed at 1001b. live weight instead of 1501b. Treatment 4 was the same as treatment 3 except that highprotein supplement was omitted altogether after 1501b. live weight; thus there were three rations involved in treatment 4—7% white fish meal from weaning to 100 lb. live weight, 3% soya-bean meal from 100 lb. to 150 lb. and no high-protein supplement thereafter.2. Growth rate and feed conversion both differed significantly between treatments. Pigs on treatment 1 grew 5·0% faster than those on treatment 4; the average growth rate for treatments 2 and 3, the difference between which was negligible, was 3·3% higher than for treatment 4. Feed conversion for treatment 1 was 5·4% better than for treatment 4 and the average for treatments 2 and 3 was 3·8% better than for treatment 4.3. Treatment differences were not significant for killing-out percentage, length, quality of fat, proportions of gammon, middle and fore-end of the cured side, thickness of streak, size of eye muscle and amount of fat over it. Some of the fat measurements differed significantly between treatments; differences in fat thickness at the shoulder, middle and rump between treatments 1, 2 and 3 were generally small, but the lowest protein level (treatment 4) resulted in carcasses with about 2% more fat along the back than the average of treatments 1, 2 and 3. These slight differences in back-fat thickness did not result in significant differences in the percentage of pigs in the highest grades.4. An economic appraisal of the results suggested that under the conditions prevailing at the time of the experiment treatment 3 would have resulted in the greatest profit per year, and the greatest profit per pig. This ration was relatively cheap compared with those of treatments 1 and 2 but it did not lead to a seriously impaired performance, as did that of treatment 4, the cheapest ration.

Comparative Value of Corn Distillers Dried Grains with Solubles, Soybean Oil Meal, and Linseed Oil Meal for Milk Production

Summary Two experiments were conducted to compare the value for milk production of corn distillers dried grains with solubles, solvent extracted soybean oil meal, and linseed oil meal when these feeds were the primary protein supplements in milking rations. Milk production was significantly higher on the feeds containing corn distillers dried grains or soybean oil meal than on mixtures containing linseed oil meal. The digestibility of the three high protein supplements was measured with lactating cows. The supplements were fed as the only concentrate, along with second cutting alfalfa hay and the digestion coefficients calculated by difference. The total digestible nutrient values on a dry matter basis were 84.8, 85.2, and 67.8% for the corn distillers dried grains with solubles, soybean oil meal, and linseed oil meal, respectively.

Effects of dietary proteins, methionine and vitamins on plasma lipids and atherogenesis in cholesterol-fed cockerels.

Methionine deficiency in the presence of a high-fat, high-cholesterol diet aggravates atherogenesis in the cockerel. High-protein, high-vitamin supplementation suppresses the atherogenic effect of a cholesterol-fat-containing diet. High-protein supplementation alone had a suppressive effect; high-vitamin supplementation had no effect. However, the combined protein and vitamin supplement was the most effective.

Treatment of Obesity with a Low Protein Calorically Unrestricted Diet

A low protein, but calorically unrestricted, diet was used to treat 42 overweight patients. The immediate results were encouraging: 32 subjects lost 100 or more grams per day, and continued to feel well. After they were discharged, however, a majority of patients returned to their previous ways of eating. At follow-up examinations 3 to 12 months after discharge, it was found that 52 per cent of the patients had regained all of their original weight, 30 per cent had remained nearly steady, and 18 per cent had continued to reduce without supervision. Prescription of a high protein supplement led to an increase in the voluntary consumption ofunprescribed calories, thus suggesting that the limitation of protein to 35 ± 5 Gm/day actually had reduced appetite. In addition, the results indicated that the routine of treatment (scheduling of meals, restriction in choice of food, regulation of activities) contributed significantly to the control of appetite. The general health remained good, and liver function, as studied by serial tests, remained unchanged by treatment. Limitation of protein appears to be a useful adjunct to the treatment of obesity; but, as with any other diet, regular medical supervision is essential. It offers a means of regulating appetite during the maintenance period that follows any successful course of reduction, and suffices as a sole measure of treatment for milder degrees of overweight.