Carcass yield and meat quality in broilers fed with canola meal

1. This study evaluated the effects of canola meal in broiler diets on carcass yield, carcass composition, and instrumental and sensory analyses of meat.

2. A total of 320 one-day-old Cobb broilers were used in a 35-d experiment using a completely randomised design with 5 concentrations of canola meal (0, 10, 20, 30 and 40%) as a dietary substitute for soya bean meal.

3. Polynomial regression at 5% significance was used to evaluate the effects of canola meal content. The following variables were measured: carcass yield, chemical composition of meat, and instrumental and sensorial analyses.

4. The results showed that carcass yield exhibited a quadratic effect that was crescent to the level of 18% of canola meal based on the weight of the leg and a quadratic increase at concentrations up to 8.4% of canola meal based on the weight of the chest. The yield of the chest exhibited a linear behaviour.

5. The chemical composition of leg meat, instrumental analysis of breast meat and sensory characteristics of the breast meat was not significantly affected by the inclusion of canola meal. The chemical composition of the breast meat exhibited an increased linear effect in terms of dry matter and ether extract and a decreased linear behaviour in terms of the ash content.

6. In conclusion, soya bean meal can be substituted with canola meal at concentrations up to 20% of the total diet without affecting carcass yield, composition of meat or the instrumental or sensory characteristics of the meat of broilers.     

Dietary rapeseed meal and the incidence of tainted eggs

1. Incorporating 0, 3, 6 or 9% rapeseed meal in the diet of brown‐egg laying birds for 28 d resulted in the production of 0, 1.2, 19.3 and 20.9% tainted eggs respectively, the first tainted eggs being laid on the fifth day.

2. During the second and third weeks the incidence of tainted eggs exceeded 20% but fell to 11.4% during the final week.

3. Omission of the rapeseed meal from the diets halted the production of tainted eggs.

4. Neither egg production nor the health of the birds was adversely affected by the treatments.

5. The taint was described as “ fishy ” or “ crabby ” and was distinctive, but the source was not identified.     

Dietary limitation of isoleucine and valine in diets based on maize, soybean meal, and meat and bone meal for broiler chickens

1. The dietary limitation of isoleucine (Ile) and valine (Val) was evaluated in broilers. Common diets were given to all broilers from 0 to 28 d of age. Experimental diets were provided from 28 to 42 d of age.

2. The experimental test diet was based primarily on maize, soybean meal, and meat and bone meal, and formulated to satisfy all nutrient recommendations with the exception of Ile and Val.

3. Diets were supplemented with L-Ile and L-Val at either 0·5 or 1·0 g kg^?1 of diet, alone or in combination. A diet composed only of commercially available amino acids and formulated to satisfy all nutrient requirements served as a positive control.

4. Body weight gain was depressed by the test diet, but recovered to a weight similar to birds fed on the positive control when Val was added to the test diet either alone or in combination with Ile. Feed efficiency improved when Val and Ile were simultaneously supplemented.

5. Abdominal fat yield was reduced with the combined supplementation of Val and Ile. Breast meat yield appeared to be more sensitive to Ile supplementation than to Val.

6. The results suggest that live performance may be more sensitive to Val, while breast meat yield was maximised with Ile supplementation. However, their combination is required for optimised growth and meat yield.     

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.     

Lupin and rapeseed meals in poultry diets: Effect on broiler performance and sensory evaluation of carcasses

1. The effect of including lupin meal (Lupinus angustifolius), with or without rapeseed meal, in computer‐formulated, least‐cost diets for broilers has, been determined.

2. In the first experiment the diets contained 0, 8 (with and without supplementary methionine, lysine, or methionine and lysine) or 16% lupin meal: addition of the lupin meal required a concomitant addition of 5 % rapeseed meal (by computer selection).

3. The diets were fed from 38 to 65 d and did not affect live‐weight but the efficiency of food utilisation was significantly worse on the 16 % lupin, 5% rapeseed meal diet than it was on the control diet.

4. The second experiment was designed as a 2 x 4 factorial to separate any effect due to rapeseed meal from that due to lupin meal, the treatments, which were applied from 1 to 62 d, being 0, 8, 16 and 24% lupin meal with and without 5 % rapeseed meal.

5. Birds gained more rapidly in the second experiment on diets containing 16 or 24% lupin meal whereas live‐weight was depressed when 5% rapeseed meal was included in the diets containing 0 or 8% lupin.

6. The 16 and 24% lupin treatments also had added dietary fat from 6 to 9 weeks of age and this may have ameliorated the adverse effect of rapeseed meal.

7. Up to 16% lupin meal and 5% rapeseed meal had no detectable effect on the colour, appearance, flavour or texture of roasted chicken meat when evaluated by a trained taste panel.     

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.     

The influence of three rapeseed meals and a mustard seed meal on egg and broiler production

A mustard seed meal free of oxazolidinethione and three rapeseed meals of low (C), medium (D) and high (E) oxazolidinethione contents were included at a rate of 12% in the diets of laying birds and of broilers. The control diets contained a similar quantity of protein as soyabean meal. In each experiment a further control group was given a suitable commercial diet.

The mustard seed meal and rapeseed meals D and E caused large and significant mortalities among laying birds. Macroscopic observations suggested that the main cause of death was probably liver haemorrhage.

Egg production, after correction for mortality, was significantly decreased by rapeseed meals D and E, and egg weight by the mustard seed meal. There were no significant treatment effects on food intake and therefore the weight of food needed for each egg produced followed fairly closely the pattern of egg production.

Overall egg production was depressed by mustard seed meal and by rapeseed meals D and E. Rapeseed meal C decreased production but not significantly.

Liver weights were not influenced by treatment, but thyroid weights of groups given rapeseed meals were significantly increased.

Broiler production was not significantly influenced either by mustard seed meal or by any of the rapeseed meals.     

Effect of ammoniation of rapeseed meal on the sinapine content of the meal

1. Two experiments were conducted to study the effects of ammoni‐ation of rapeseed meal on its sinapine content.

2. In the first experiment, five samples of a low‐glucosinolate meal (produced from Regent, Candle or Tower cultivars) and one sample of a high‐glucosinolate meal were eluted by one passage of ethanol ammoniated to concentrations of 0.2, 0.5 or 1.0 M NH₃ at the ratio of 2 1 ammoniated ethanol/kg meal. Elution with 1.0M ammoniated ethanol decreased the sinapine content of the meals by as much as 80%.

3. In the second experiment, four low‐glucosinolate meals (from Candle cultivar) from a pilot processing plant were used. Two of the meals were obtained by sparging during desolventising with or without anhydrous ammonia (50 g anhydrous ammonia/kg meal) and two of the meals were produced by sparging during desolventising with or without hydrous ammonia (50 g anhydrous ammonia and 50 g steam/kg meal). Ammonia with steam caused the greatest decrease (65%) in sinapine content.

4. Total glucosinolate and 5‐vinyl‐2‐oxazolidinethione concentrations in the meals were also decreased (17 to 35%) by the ammoniation treatments in experiment 2.     

The use of rapeseed meals and a mustard seed meal as a protein source in diets for laying pullets

1. Three experiments with laying pullets were carried out in which rapeseed meals (B. napus and B. campestris) and a mustard seed meal (B. juncea) formed 12% of the diet.

2. Dietary rapeseed had no effect on the onset of lay when fed from 17 weeks of age but caused a delay when fed from 10 weeks of age: changing to a control soyabean diet for the laying period resulted in normal egg production.

3. Diets containing B. napus but not B. campestris consistently depressed egg production and reduced egg weight in one experiment. Mustard seed meal did not affect performance.

4. Significant number of eggs with a “fishy” taint were laid by brown‐egged birds fed on a diet containing rapeseed.

5. Thyroids of birds fed on rapeseed meal diets during the laying period were significantly heavier than those of birds fed on diets containing mustard seed or soyabean.

6. The enlargement of the thyroid gland is probably related to the oxazolidinethione content of the rapeseed.     

Utilisation of ambadi (hibiscus cannabinus) meal by growing chickens

1. Experiments were conducted to compare the utilisation of ambadi meal with that of peanut meal in WL chicks and broilers.

2. Ambadi meal, either expeller‐processed (135.5 g and 271 g/kg) or solvent‐extracted (130.5 g and 261 g/kg), was incorporated at the expense of the peanut meal protein used in the reference diet (180 g/ kg) into diets which were fed to WL pullets (experiment 1) from 1 to 56 d of age. The weight gains and food efficiencies of the chicks fed on the ambadi meal and reference diets were similar.

3. With broilers (experiment 2) the weight gains were also similar, at all dietary concentrations of ambadi meal (89 to 356 g/kg), to those on the reference diet (235 g/kg peanut meal) from 14 to 35 d of age. However, food intake was higher on the ambadi meal diets and this resulted in significantly poorer food efficiency when compared to the reference diet.

4. High food intake and consequently low food efficiency was still evident in birds given ambadi meal diets even when ambadi meal replaced peanut meal on a digestible protein basis (experiment 4) or when ambadi meal (expeller or solvent‐extracted) was subjected to physical treatments such as soaking, autoclaving and pelleting (experiment 5).

5. The transit time of food through the gastro‐intestinal tract of broilers was faster when the diet contained ambadi meal than peanut meal. The higher food intake seen in broilers given diets containing ambadi meal could be the consequence of the fast rate of food passage.

6. Ambadi meal in diets for broilers resulted in significant increase (P<0.05) in the lengths of jejunum plus ileum and caecum. Fibre from the ambadi meal might have influenced the changes in the dimensions of gastro‐intestinal tract as well as in the transit time of food.     

Studies on the effect of lysine and methionine supplementation of a high‐protein maize‐soyabean diet and of a low‐protein barley‐white fish meal diet on the performance of caged layers

Selected literature relating to the amino acid supplementation of layers’ diets is reviewed and the results of two experiments are presented.

In the first experiment a basal soyabean meal diet (14.3 per cent crude protein) was supplemented with L‐lysine and DL‐methionine, singly and together. Supplementation of the basal soyabean diet with the amino acids caused no significant effects on egg production, mean and total egg weight or food conversion efficiency. None of the soyabean diets proved as satisfactory for egg production or food conversion efficiency as a fish meal control diet (16.9 per cent crude protein).

In the second experiment the effect of adding 0.1 per cent each of L‐lysine and DL‐methionine or 0.2 per cent each of l‐lysine and DL‐methionine to a low fish meal diet (2.5 per cent fish meal) was examined. The addition of 0.2 per cent of each amino acid caused an increase in egg production.

Mean egg weight was improved by the addition of amino acids at both levels although this effect was not statistically significant. Comparison of the low fish meal diets with a fishmeal control diet (10 per cent fishmeal) showed that at the 0.2 per cent addition of amino acids, egg production, total egg weight and food conversion efficiency were better than on the 10 per cent fish meal control diet.

Two breeds, light and medium hybrids were used in both experiments.

The results are discussed with reference to their practical significance.     

Guar meal in diets for broiler chickens

1. In two experiments each involving 2 000 Ross 1 broiler chickens in floor pens from 0 to 56 d of age, the effects of including guar meal at 50, 100 or 150 g/kg of the diet were investigated.

2. During the 0 to 28‐d period diets containing 50 or 100 g guar meal/kg supported only 85 and 69%, respectively, of the growth supported by the control diet, whereas during 28 to 56 d, birds fed on diets containing 100 or 150 g guar meal/kg gained 90 and 86% of the weight gained by control birds.

3. Neither toasting the meal, steam pelleting diets containing the meal nor supplementing these diets with 5 g methionine/kg had any appreciable effect on performance.

4. Addition of either of two enzyme preparations, MKC hemicellulase or betaganase M, improved growth; birds receiving 100 or 150 g guar meal/kg gaining 96 and 89%, respectively, of the weight gained by control birds from 28 to 56 d of age.     

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.     

Incorporation of triticale in layer diets

1. Diets containing either maize or triticale were fed unsupplemented or supplemented with meat meal or groundnut oil to White Leghorn pullets for two periods of 11 weeks each.

2. The egg production of birds fed on the unsupplemented triticale diet was significantly higher than that of the birds fed on the unsupplemented maize diet, but was not significantly different from that of the birds fed on the maize plus meat meal diet.

3. Protein quality of the unsupplemented triticale diet as judged by efficiency of nitrogen retention was similar or inferior to that of the unsupplemented maize diet.

4. The higher protein content of triticale and the increased intake of these diets seemed to be responsible for the better performance observed.

5. Addition of groundnut oil to the triticale diet did not improve either egg weight or production.

6. It is concluded that the quantitative substitution for triticale of maize does not adversely affect egg production and egg weight.     

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.     

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.     

Utilisation of leucaena leaf meal by broilers

1. The effect of including Leucaena (Leucaena leucocephala) leaf meal (LLM) in broiler diets was investigated employing LLM at 0, 50, 100, 150 and 200 g/kg diet. Experiments were also conducted to investigate whether reduced food intake of diets containing LLM is responsible for the growth depression.

2. LLM appears to be a good source of protein and calcium.

3. Food intake was not significantly affected (P>0.05) with dietary LLM inclusion up to 200 g/kg.

4. Inclusion of LLM up to 150 g/kg diet did not influence significantly (P>0.05) the performance of broilers in terms of body weight gain and food efficiency. However, inclusion of LLM at 200 g/kg diet had an adverse effect on weight gain and food efficiency, when compared to other dietary treatments. The profitability over food costs was low with the 200 g LLM/kg diet compared to those of other diets.

5. It may be inferred from these experiments that LLM can safely be included in broiler diets up to 150 g/kg.

6. Studies using force‐feeding and restricted feeding techniques indicated that reduced food intake was not responsible for the growth depression in diets containing higher amounts of LLM.     

The nutritional value of salseed (Shorea robusta) meal for growing chicks

1. Salseed meal contains 98 g crude protein, 22 g ether extractives, 450 g available carbohydrate and 117 g tannins per kg.

2. From the chemical analysis the metabolisable energy (ME) content of salseed meal would be expected to be 11.22 MJ/kg. In vivo assay with chicks yielded values considerably less than this, 7.1 MJ/kg being found at an inclusion rate of 150 g/kg diet.

3. As the inclusion rate of salseed meal was increased to 300 g/kg, dietary ME and the digestion and retention of dietary protein decreased.

4. More than 50 g salseed meal/kg in the diet of chicks resulted in poor growth rate and food conversion.     

Biological availability of selenium and phosphorus in fish meal as affected by condition of fish and type of meal

1. Experiments were conducted to determine the effects of the condition of the fish and of processing procedures on the biological availability of selenium and phosphorus in fish meals.

2. In fresh fish processed to whole fish meal the biological availability of selenium was estimated as 77%, in fresh fish processed to pressed‐cake fish meal it was 59% and in partly‐decomposed fish processed to whole fish meal it was 51%.

3. When the phosphorus content of the test diet was 2–51 g/kg the biological availability was 88% and unaffected by the condition of the fish and the method of processing.     

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.