Effects of high inclusion rates of salseed meal in the diet of chicks

1. Starter diets containing either maize or salseed meal to replace the maize were fed to chicks over a period of 2 weeks.

2. Growth rate, food intake, food utilisation and proportion of dietary nitrogen retained were much poorer in chicks receiving salseed meal.

3. The chicks receiving salseed meal developed pathological lesions in liver and kidney.

4. The red blood cell count, white blood cell count, haemoglobin concentration and packed cell volume of the chicks receiving salseed meal were lower than those of chicks receiving maize.

5. The apparent metabolisable energy value of salseed meal was determined as 6.83 MJ/kg.     

Lysine requirement of broiler chicks as affected by protein source and method of statistical evaluation 1

1. An experiment was designed to test if the lysine requirement, expressed as g lysine/kg CP, was the same for several protein sources.

2. Groundnut meal, groundnut meal adjusted with indispensable amino acids or sesame meal supplied the dietary CP at 180 g/kg diet. Increments of lysine (1.5 g/kg diet) were added to each of these diets.

3. The gain, food intake and food efficiency responses of broiler chicks were analysed using a quadratic equation and a two‐slope method. An estimate of lysine requirements was also obtained from a survey of college students.

4. The different methods produced widely different estimates of lysine requirement.

5. The average lysine requirement was estimated at 50.1 g lysine/kg CP for groundnut meal, 61.7 for adjusted groundnut meal and 54.9 for sesame meal.

6. Reasons for the effect of statistical analysis and protein source on lysine requirement are discussed.     

Utilisation of squilla meal (a novel animal protein source) by Broilers

1. The nutritive value of squilla meal, which contained 339 g crude protein, 18.6 g ether extract, 72.8 g calcium, 17.2 g phosphorus and 7.13 MJ of apparent metabolisable energy/kg, was examined in 5 experiments with broilers.

2. Squilla meal contained less lysine (3.45 vs 6.74 g/16g nitrogen) and methionine (1.02 vs 1.86/16 g nitrogen) dian fish meal, had a lower protein digestibility coefficient (0.66 vs 0.72) and a lower gross protein value (68% vs 74%).

3. By gradually replacing the fish meal with squilla meal in isocaloric, isonitrogenous broiler diets it was shown that there was a linear decrease in broiler weight gain; efficiencies of food utilisation were also lower at all squilla meal substitution rates. Inclusion of squilla meal in the diets increased intestinal lengths.

4. Addition of a proteolytic enzyme to the diets containing squilla meal restored broiler weight gain and efficiency of food utilisation to that of birds fed on the control diet.

5. Diets containing autoclaved squilla meal resulted in reduced weight gain although efficiency of food utilisation was not affected.     

Hydrolysed feather protein as a source of amino acids for broilers

1. The inclusion of 25 g hydrolysed feather meal (HFM) in each kilogram of diet (floor experiment) and 60 g/kg (cage experiment) did not depress performance.

2. Chemical tests indicated 72.5% of the total lysine in HFM was available.

3. Total lysine concentration of 11.3 g/kg diet maximised performance during the period 0 to 34 d.

4. Reduction in dietary methionine content during the period 0 to 34 d from 4.2 g/kg to 3.2 g/kg did not depress performance on diets containing 60 g HFM/kg.

5. The results indicate that at least 57% by weight of the total sulphur amino acid requirement of broilers can be provided by cystine.     

A comparison of methods for estimating the metabolisable energy of a sample of grass meal

1. The inclusion of grass meal in the diets of broilers and laying hens reduced food intake and, as a consequence, the apparent metabolisable energy (AME) and nitrogen‐corrected AME (AME_N) values estimated for the grass meal were artificially low.

2. With young broilers the AME and AME_N values of a sample of grass meal were estimated to be 5.97 ± 0.45 and 6.05 + 0.46 MJ/kg dry matter respectively.

3. With adult laying hens the AME and AME_N values of the sample of grass meal were estimated to be 5.36 ± 1.04 and 6.26 ± 0.96 MJ/kg dry matter respectively and the corresponding true metabolisable energy (TME) and nitrogen‐corrected TME (TME_N) values were shown to be 9.12 ± 1.25 and 8.66 ± 1.33 MJ/kg dry matter.

4. It was further illustrated that if the dietary intake of the adult birds had been 100 g/d, the AME value of the grass meal would have been estimated as 8.33 MJ/kg dry matter.     

The performance of male ducklings given starter diets with different concentrations of energy and protein

1. Male ducklings were fed for 14, 21 or 28 d on diets containing 180, 200, 220 or 240 g of protein and 10.88 or 12.55 MJ of metabolisable energy (ME) per kg, followed by a common finisher diet until 56 d of age.

2. Birds given starter diets with 220 or 240 g of protein per kg were significantly heavier at 14 d than those given diets with 180 or 200 g protein per kg.

3. There was no significant benefit in feeding diets with protein levels greater than 180 g/kg for more than 14 d.

4. Diets with only 10.88 MJ of ME per kg produced significantly lighter birds at 28 and 56 d of age and significantly reduced food conversion efficiency up to 14 d.     

The nutritional value of algae for poultry. Dried chlorella in layer diets

1. The nutritional value of a sample of algae meal, mainly Chlorella, was assessed in an experiment with laying hens. The algae meal was that described by Lipstein and Hurwitz (1980).

2. Diets formulated by linear programming contained up to 120 g algae meal/kg with supplementary DL‐methionine.

3. There were no significant effects of dietary algae meal on egg output, food conversion or egg‐shell quality. Thus algae meal at the concentrations tested can be a useful substitute for soyabean meal in diets for laying hens.

4. High concentrations of dietary algae meal caused a deep yellow yolk colour of acceptable appearance.     

The use of n‐paraffin‐grown yeast as the main source of protein in diets for chicks

1. n‐Paraffin‐grown yeast and a mixture of soyabean meal and fish meal were compared in the net protein utilisation (NPU) test, and as protein supplements in diets for broilers up to 4 weeks of age.

2. The difference between the NPU values, 0.66 for yeast and 0.80 for the soyabean meal and fish meal mixture, could largely be attributed to the high nucleic acid content of the yeast.

3. Chicks given the diet containing yeast (190 g/kg) did not grow as rapidly as those given the soyabean meal and fish meal reference diet, and the reduced growth could only partly be explained by a marginal deficiency of methionine.

4. Food conversion efficiency with the yeast diet was improved by maize oil while responses to α‐tocopheryl acetate and sodium selenite were inconsistent.

5. Chicks grew well when yeast replaced fish meal in the mixture of soyabean meal and fish meal, and when fish meal (194 g/kg diet) was the sole protein supplement.     

Effect of soybean meal substitution by different concentrations of sunflower meal on egg quality traits of white and coloured dwarf dam lines

1. The effect of soybean meal substitution by different concentrations of sunflower meal on egg quality traits of white and coloured dwarf dam lines was investigated.

2. A total of 144 dwarf hens (38 weeks of age) from the same hatch were randomly divided into 12 groups of 12 birds (4 dietary treatments × 3 replicates).

3. A 2 × 4 factorial design was used to study the effect of 2 lines (Factor A) and substitution of soybean meal (SBM) with 4 concentrations (0, 10, 15 and 20%) of sunflower meal (SFM) [Factor B] on egg quality traits of dwarf dam line hens.

4. All the diets were designed to be isocaloric (11?3 MJ ME/kg) and isonitrogenous (180 g/kg crude protein) The duration of the experiment was 12 weeks.

5. Analysis of variance indicated a highly significant line effect. There were non-significant effects of substitution of soybean meal with different concentrations of sunflower meal on egg quality traits except for Haugh unit.

6. White plumaged dwarf broiler breeder dam line produced significantly fewer, but larger, eggs than coloured dwarf dam line hens.     

The nutritional value of algae for poultry. dried chlorella in broiler diets 1

1. The nutritional value of a sample of algae meal, mainly Chlorella, was assessed in two chick and two broiler trials. The algae were drum‐dried after harvesting from sewage ponds by centrifugation.

2. Diets formulated by linear programming contained between 60 and 150 g algae meal/kg by substituting algae meal and sorghum for fish meal, soyabean meal and maize in a control diet.

3. The effects of the dietary algae meal ranged from nil to a significant depression of growth rate and food utilisation. In certain cases growth retardation was associated with depressed food consumption.

4. The metabolisable energy concentration of the algae meal was estimated to be 11–62 MJ/kg and the nitrogen absorption coefficient 0.81.     

Egg discolouration effects of including screw‐press cottonseed meal in laying hen diets and their prevention

The egg discolouration effects of including a screw‐press cottonseed meal (CSM), containing 68.2 g residual lipid/kg, 290 mg cyclopropenoid fatty acids (CPFA)/kg and 1226 mg free gossypol/kg, in laying hen diets at 300 g/kg were examined.

2. Discolouration prevention methods included treating the meal with ferrous sulphate heptahydrate (FSH), in solution or as crystals, at a 4:1 weight ratio of iron to free gossypol (experiment 1), and reducing its residual lipid (CSL) content to 4.2 g/kg by hexane extraction (experiment 2).

3. In freshly laid eggs, no discolouration was observed when hens were fed a CSM‐based diet containing 250 mg free gossypol/kg and 87 mg CPFA/kg in experiment 1, but slightly brown yolks were produced in experiment 2.

4. Storage of the eggs at 22°C led to yolk mottling, an effect believed to be the initial stages of the brown yolk discolouration.

5. Storage of the eggs at 5°C resulted in enhancement of the brown yolk discolouration, apricot discolouration on surfaces of most yolks and pink albumen discolouration. These effects were prevented when the CSM was extracted with hexane. Apricot yolk and pink albumen discolourations were also produced when hens were fed a non‐CSM diet containing crude CSL at 20.5 g/kg.

6. Dietary CSL increased egg fat saturation, altering the ratios of stearic to oleic, palmitic to palmitoleic and heptadecanoic to hepta‐decenoic fatty acids.

7. Treatment of CSM with FSH reduced the slight brown yolk discolouration in fresh eggs (experiment 2) and the yolk mottling in warm‐stored eggs. Both in solution and as crystals, FSH prevented the enhancement of brown yolk discolouration in cold‐stored eggs, leaving most eggs with apricot yolk and pink albumen discolourations.

8. Treatment of CSM and CSL with FSH reduced the CPFA‐related effects on yolk fat saturation, and the colour and pH changes in cold‐stored eggs.

9. Exposure of yolks to ammonia vapour provided a useful test to predict the development of the gossypol‐related brown discolouration in stored eggs.     

Transfer of 125I to eggs in hens fed on diets containing high‐ and low‐glucosinolate rapeseed meals

1. An experiment was designed to evaluate the effect of the gluco‐sinolate content of rapeseed meal on the transfer of dietary iodine to eggs.

2. The experimental diets, containing two concentrations (50 or 100 g/kg) of high‐ or low‐glucosinolate rapeseed meal and a diet, devoid of rapeseed meal, all supplemented with 0.3 mg I/kg were given to laying hens for 6 weeks before oral administration of ¹²⁵I daily for 11d.

3. The percentage of ¹²⁵I transferred to egg yolk was significantly reduced by the inclusion of high‐glucosinolate rapeseed meal but not by low‐glucosinolate meal.

4. Determination of the total iodine content of egg yolk indicated that there was some reduction in the transfer of dietary iodine to eggs even with the low glucosinolate rapeseed meal.     

Grass meal as an ingredient in diets for broiler chickens

1. Six diets of equal energy and nitrogen contents containing between 0 (control) and 125 g grass meal/kg were each fed to 4 groups of 42 male and 4 groups of 42 female broiler chicks, in floor pens, from 0 to 56 d of age.

2. Increments of 25 g grass meal/kg and 7.3 g maize oil/kg replaced a mixture of soyabean, wheat and barley meals in the control diet.

3. Gain: food ratio (y) of the birds decreased linearly as dietary grass meal content (x) increased such that y = 0.4295 ? 0.0032x.

4. Carcass analyses indicated that the decrease in gain : food ratio was caused by less deposition of body fat.

5. Skin colour became significantly yellower as the dietary grass meal content increased.     

Rapeseed meals in broiler diets: Effect on performance and sensory evaluation of carcasses

1. The effect of including rapeseed meal (RSM) in lieu of soyabean meal in broiler diets was determined.

2. Live‐weight gains, from 8 to 63 d, were depressed when the diet contained 150 g RSM/kg and there was a highly significant negative correlation between weight gain and inclusion rate of RSM over this period.

3. The efficiency of food utilisation was worse when the diet included 150 g solvent RSM/kg than when it contained no RSM: food efficiency was consistently poorer whenever RSM was included in the diet but the difference was significant only when the diet contained 10 g tallow/kg.

4. Carcasses from birds fed on diets containing 10 g tallow/kg had a better appearance than those from birds on diets containing 30 g tallow/kg, while the flavour of meat from birds fed on a diet containing 150 g solvent RSM/kg treatment was adversely affected. However, up to 100 g solvent RSM/kg may be included in broiler diets without affecting appearance, taste, texture or acceptability of the meat.

5. Inclusion of 50 g or more, solvent RSM/kg reduced growth rate and worsened food efficiency.     

Supplemental dietary L‐tryptophan effects on growth,meat quality,and brain catecholamine and indoleamine concentrations in Turkeys

1. An experiment was conducted to investigate the effects of feeding supplemental tryptophan during the two weeks before market on growth, mortality during transportation, meal quality and brain neurotransmitter concentrations in male turkeys.

2. Brain serotonin, 5‐hydroxyindoleacetic acid and norepinephrine concentrations were increased dose‐dependently with 1.0, 2.0 and 3.0 g/kg supplemental dietary tryptophan.

3. Supplemental dietary tryptophan had no effect on body weight gain, food intake, food efficiency or mortality.

4. Carcase and individual thigh weights were significantly heavier in those birds fed l.0 g/kg supplemental tryptophan.     

Effects of nutrient concentration and dietary presentation on performance of dwarf hens

1. Diets containing 170 or 190 g protein/kg and 10.9 or 11.7 MJ ME/kg in all combinations were offered to dwarf hens in two dietary presentations: a complete mash or a form in which part of the protein and calcium contents were presented as soyabean meal pellets and limestone grit respectively.

2. Egg production and egg mass output were higher with the 190 g protein/kg diets.

3. Lower‐energy diets gave better egg production, while higher‐energy diets containing 190 g protein/kg improved food conversion efficiency.

4. Separation of protein and calcium constituents tended to give better egg production, food conversion efficiency, shell thickness and egg mass output.     

Comparison of wheats of high or conventional protein content with added lysine in diets for layers

1. High‐protein wheats (196 or 210 g/kg) were compared with conventional wheat (163 or 162 g/kg) in layers’ diets in three experiments.

2. In diets of 160 g protein/kg without added lysine, high‐protein wheats caused lower rates of production and egg size than conventional wheats in White Leghorns. Lysine supplementation of the former diets eliminated these differences.

3. The improvements in egg production and egg weight were significant with 1 g additional lysine/kg and egg production tended to improve further with 2 g additional lysine/kg, as did egg weight with all subsequent additions, but not significantly so.

4. With diets containing high‐protein wheats supplemented with lysine, high egg production and egg weight could be obtained without a protein supplement (e.g. soyabean meal).

5. In broiler‐breeders egg production was lower and food conversion poorer with high‐protein wheat despite added lysine.     

Diets for growing pullets containing unusual ingredients and varying concentrations of cereals,including no cereals

1. Growing pullets (Shaver 288) were fed on diets containing about 150 or 100 g protein/kg and 800, 600, 300 or 0 g of a mixture of equal parts of wheat and barley, from 12 to 20 weeks of age.

2. Varying mixtures of dried poultry manure, dried grass, dried potato meal, poultry offal meal and tallow were substituted for the cereal portion, so that calculated metabolisable energy values and methionine and lysine concentrations were constant within each protein series.

3. Within the 150 g protein/kg series, body weight at 20 weeks of age was similar for diets containing 800, 600 and 300 g/kg cereal whereas with the cereal‐free diet body weight was depressed by 10%; with the latter diet sexual maturity was also delayed by nearly 4 d though subsequent egg production was unimpaired.

4. Within the 100 g protein/kg series, body weight at 20 weeks of age and subsequent egg production, calculated either to a fixed age or for a given time spent laying, were depressed by diets containing 300 or 0 g cereal/kg, compared with diets containing 800 or 600 g/kg.

5. Dietary concentrations of dried poultry manure up to 250 g/kg had no effect on mortality.     

Studies on the toxic effects of crambe meal and two of its constituents, 1‐cyano‐2‐hydroxy‐3‐butene (GHB) and epiprogoitrin,in broiler chick diets

1. Studies were undertaken to determine a safe inclusion rate for crambe (Crambe abyssinica) meal in broiler chick diets, and to determine the mechanism for adverse effects by investigating its constituents; l‐cyano‐2‐hydroxy‐3‐butene (CHB) and 3‐butenyl glucosinolate (epi‐progoitrin, E‐PG).

2. Crambe meals were prepared to differ in E‐PG (19, 36 and 40 g/kg) and CHB contents (0.1, 0.7 and 1.9 g/kg), and with either active or inactive thioglucosidase.

3. Meals were fed to 7‐d‐old broiler chicks at 50 or 100 g/kg of the diet for 12 or 13 d. In separate studies, isolated E‐PG or CHB were mixed into the diet or administered by gavage to 7‐d‐old broiler chicks in amounts equivalent to 50 or 100 g/kg crambe meal diets for 10 and 12 d, respectively.

4. Weight gain decreased (P<0.05) in chicks fed on the high glucosinolate crambe diets or isolated E‐PG. Food consumption decreased (P<0.05) in chicks fed on the diet containing the high E‐PG meal with active enzyme.

5. Mild liver lesions and increased serum aspartate aminotransferase were found in chicks fed on the diet containing the high glucosinolate meal with active enzyme. Other organs, including thyroids, were normal.

6. Commercially‐processed crambe meal appeared safe at an inclusion rate of 50 or 100 g/kg diet, but could not be recommended at this point for long term feeding.     

Replacement of groundnut cake by dried poultry manure in the diets of laying hens

1. The effect on food consumption by pullets when dried poultry manure (DPM) replaced part of dietary groundnut cake depended on the strain of the birds: in two of the three hybrids food consumption was not affected when up to 100 g DPM/kg was fed.

2. Increases in food consumption were accompanied by increases in egg production.

3. The food required per dozen eggs was improved by up to 100 g dietary DPM/kg and variation in the sizes of eggs laid depended on the hybrid.

4. Concentrations of DPM up to 100 g/kg did not affect the water‐soluble nitrogen content of the egg but the crude albumen nitrogen content was depressed at concentrations of 80 g/kg or above.

5. Feeding DPM to laying pullets depressed body weight.