Ratification of broiler carcase condemnations in poultry meat inspection

1. In the years 1985 to 1989 decisions (approvals and condemnations) made by poultry meat inspectors were examined by the individual reinspection of 26,815 broiler carcases.

2. The extent of agreement between inspection and revision ranged between 83.2 and 86.2%.

3. Agreement between inspectors and revisors was higher for the category of approved birds than for the condemned category.

4. Differences in the criteria used to assess the birds were observed.

5. The conclusion was drawn that findings in meat inspection require further discussion to reach an agreed standard.     

Effects of ascorbic acid and α-lipoic acid on performance and meat quality of broilers subjected to heat stress

1. The present study was aimed to investigate the effect of adding ascorbic acid or α-lipoic acid to to the diet of broilers exposed to heat stress on performance and meat quality.

2. Heat stress caused a decrease in final body weight and feed consumption, whilst ascorbic acid (AA) and α-lipoic acid (ALA) partly prevented the decrease in final body weight of males.

3. While heat stress increased the pH values of broiler drumsticks and breast meat, AA and ALA partly reduced this increase. For meat quality, AA and ALA reduced the adverse effects on the relative yellowness value, particularly on d 14 of storage.

4. It was determined that heat stress affected the microbiological quality of meat adversely, and that AA and ALA alleviated this effect to a certain extent.

5. In conclusion, while heat stress affected body weight gain and meat quality adversely, the supplementation of the ration with AA and ALA partly alleviated these adverse effects.     

Effect of electrical and gaseous stunning on the carcase and meat quality of broilers

1. The aim of the experiment was to investigate the effect of gaseous stunning methods on the carcase and meat quality of broilers (dead weight 1.0 to 2.3 kg) in comparison with electrical stunning.

2. Two replicates of broilers (age 54 and 59 d respectively) were stunned in carbon dioxide, in argon or by electric current, and the carcases were plucked either by a mechanical plucker or by hand.

3. Carcase and meat quality were evaluated to determine the effect of these stunning treatments and plucking methods. The quality factors measured included pH at 20 min post‐mortem, ultimate pH, texture and colour of the pectoralis major muscle, and the incidence of carcase appearance defects, cooking loss, broken bones and bruises in the breast and leg muscles.

4. Stunning method had a significant effect on pH at 20 min, ultimate pH, texture and colour of breast meat. Plucking method had a significant effect on the cooking loss and texture.

5. Argon stunning resulted in fewer muscle haemorrhages, a more rapid early post‐mortem fall in pH and more tender breast meat than in the electrically stunned broilers; carbon dioxide stunned broilers had intermediate values for pH decline and meat tenderness but were not significantly different from argon stunning regarding muscle haemorrhages.

6. Appearance defects occurred to a similar extent in all the stunning methods and mechanical plucking resulted in 4 times as many defects compared with hand plucking; the incidence of broken bones was higher in mechanically plucked broilers than in hand plucked carcases.

7. Gaseous stunning of broilers produced relatively better quality carcases and meat than electrical stunning, and therefore may have commercial advantages.     

Effects of dietary chromium chloride,nicotinic acid and copper sulphate on meat of broilers

1.?Combinations of chromium and copper were added to the diet to assess their effects on broiler meat characteristics.

2.?For this purpose 175 one-day-old broiler chicks were divided into 7 equal groups and were given treatment feeds containing copper sulphate, chromium chloride and nicotinic acid in different combinations.

3.?The study was carried out for 5 weeks and samples were collected at the end of 15, 29 and 35 d of treatment and at 42 d after a withdrawal period of one week.

4.?Cholesterol content had decreased significantly in breast meat at d 29 in all treatment groups. In thigh meat, it decreased significantly at d 29 in groups receiving two concentrations of chromium + two concentrations of copper. Cholesterol content remained lower even after withholding the treatment for one week.

5.?Crude fat content decreased significantly in breast meat in all treatment groups. In thigh meat, at d 29, a significant reduction in crude fat was observed only in birds receiving low chromium and high copper.

6.?Crude protein at d 29 increased significantly in breast meat of birds receiving low chromium and high copper, and low or high chromium, while it decreased significantly in treatment groups after withholding the treatment. In thigh meat, at d 29, it increased significantly in treatment groups but decreased significantly after withholding the treatment.

7.?It was concluded that chromium and copper, along with nicotinic acid, have modulating effects on broiler meat under tropical conditions.     

Utilisation of dried poultry manure by growing chickens fed on a practical diet

1. Dried poultry manure (DPM) has been tested as a replacement for groundnut cake in poultry diets.

2. Body weight gain, and the efficiency of food conversion were improved when the diet contained 50 g DPM/kg but higher rates of inclusion (100 or 150 g/kg) depressed growth.

3. Birds fed on diets containing 50 g DPM/kg yielded meat of comparable quality to those fed on the control diet whereas those fed on diets containing more DPM yielded meat containing more fat and less water.

4. The percentage moisture in the meat was inversely related to the lipid content.

5. Nitrogen retention was comparable in all groups.     

Carcass characteristics,composition, physico-chemical,microbial and sensory quality of emu meat

1. In order to investigate whether emu meat is a potential red meat alternative, this work was carried out with the objective of studying the carcass characteristics, proximate composition, physico-chemical and microbial characteristics and sensory attributes of emu meat.

2. Carcass characteristics clearly indicate that emus are a significant source of lean meat, fat, skin and edible by-products and these findings confirm earlier reports.

3. Proximate composition of emu meat indicated higher protein and ash content and lower fat, total lipids and cholesterol content than meat from other meat animals.

4. The pH, water holding capacity, collagen content and solubility, protein extractability, muscle fibre diameter and Warner–Bratzler shear force values of emu meat are similar to the earlier reports for meats from other food animals.

5. Emu meat is dark, cherry red in colour with significantly higher myoglobin content and the myoglobin is more prone to oxidation as evidenced by higher initial metmyoglobin percentage. The initial thiobarbituric acid reactive substances (TBARS) values and free fatty acids percentage in emu meat were higher than those in meats from other species.

6. Sensory evaluation of cooked emu meat curry revealed highly acceptable scores relative to goat meat curry, the most preferred meat in India.

7. The study shows the potential of emu meat as a new source of low fat, quality meat proteins. However, more studies are required to elucidate the effect of age, sex, muscles, pre-slaughter and post-slaughter factors on different carcass and meat quality characteristics.     

Improving the nutritional quality and shelf life of broiler meat by feeding diets supplemented with fermented pomegranate (Punica granatum L.) by-products

1. Four experimental diets containing 0, 0.5, 1.0 and 2.0% fermented pomegranate by-products (FPB) were supplied to 320d-old broilers to evaluate the effects of FPB on growth performance, nutritional composition, fatty acid profile and oxidative stability of meat.

2. Dietary supplementation of FPB linearly increased the weight gain and feed intake of broilers with linear reduction in feed conversion ratio.

3. The crude protein, iron, magnesium, and sodium content were linearly higher, whereas cholesterol was linearly lower in the breast meat of FPB-supplemented broilers. In thigh meat, linearly lower ether extract and cholesterol with higher moisture was noted in response to increasing levels of FPB.

4. The proportion of saturated fatty acids was both linearly and quadratically lower in breast and thigh meat, whereas those of monounsaturated fatty acids of breast (linear and quadratic) and n-3 fatty acids of breast and thigh (linear) meat was higher in the FPB-supplemented broilers. The n-6/n-3 ratio of breast meat was linearly lower in response to FPB supplementation. The hypocholesterolaemic to hypercholesterolaemic ratio of thigh meat was higher in the FPB-supplemented groups.

5. The thiobarbituric acid reactive substances and pH value were lower in the breast and thigh meat of FPB-supplemented broilers.

6. Thus, additive supplementation of the diet with up to 2% FPB improved the nutritional quality, fatty acid profile and shelf life of broiler meat.     

Effect of stunning method,carcase chilling temperature and filleting time on the texture of turkey breast meat

1. Three hundred and sixty turkeys comprising 16 week‐old stags (medium stags), 22 week‐old stags (large stags) or 52 week‐old hens (hens) were stunned with either argon‐induced anoxia, 30% carbon dioxide in argon with 2% residual oxygen (gas mixture) or electric current and the carcases were processed under commercial conditions. The carcases were chilled at either 16°C or 3°C using a commercial immersion chiller and the carcases were held in a cold room (3°C).

2. Breast muscles (pectoralis major) were filleted at either 2, 3, 5 or 18 h post‐mortem, and pH and muscle temperature were measured at the time of filleting for the medium and large stags. The breast fillets removed soon after killing were stored at 3°C until transported to the laboratory.

3. All the breast fillets were cooked to an internal muscle temperature of 85°C and their texture was measured instrumentally. The fillets were weighed before and after cooking to determine the proportional cooking loss.

4. The results showed that, for electrical stunning, the rate of pH fall soon after killing differed between the bird types, and it resulted in a variable texture in the breast meat when filleting was performed soon after killing. The medium stags had a relatively slower rate of pH fall and filleting them soon after killing resulted in tougher breast meat.

5. By contrast, in all the three bird types, gas stunning resulted in a rapid pH fall soon after killing and produced tender breast meat at all the filleting times tested.

6. The cooking loss was higher in the large stags than in the medium stags or hens.

7. Stunning turkeys by anoxia or 30% carbon dioxide in argon would enable filleting to be performed soon after killing, and produce less variable‐and more tender breast meat.     

Traits influencing the hatching performance of Japanese quail eggs

1. Japanese quail eggs from moderately heavier sires showed superior fertility; while fertile eggs from moderately heavier dams hatched slightly better than the eggs from lighter dams.

2. Higher rates of fertility and hatchability of Japanese quail eggs were observed from parents of 10 to 19 weeks of age, with peak fertility and hatchability at 14 and 12 weeks of age, respectively.

3. Sex ratios of 1:2 to 1:5 gave comparable fertility and hatchability results.

4. The hatching performance of quail eggs from cage and deep litter reared breeders was comparable.

5. Fertility and hatchability were directly proportional to the egg weight.

6. Quail egg shell colour, tints and blotches were found to influence hatching performance.

7. Storing quail eggs at 16 ± 2°C and 75 ± 5% relative humidity for more than 4 d reduced hatchability.

8. Hatchability of eggs stored at room temperature was improved if they were sealed in polyethylene bags.

9. Provision of light during the first 14 d of incubation resulted in a photo‐acceleration of about 3.2 h.     

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.     

Effect of oiling on internal quality of eggs stored at 28 and 12°G

1. The effects of spraying linseed oil on naturally clean eggs, subsequently stored for 24 d at 28 °C were studied.

2. Oiling slowed the decline in albumen height (Haugh units) to that which occurred in unoiled eggs stored at 12 °C.

3. Oiling slowed the increase in albumen pH equally at 28 and 12 °C.

4. Oiling markedly decreased the weight loss of eggs stored at either temperature.

5. Oiling and temperature of storage were without effect on the whipping volumes of either albumen or unseparated albumen and yolk.     

Metabolic and anatomical adaptations of light‐bodied chicks to intermittent feeding

1. Chicks of a light‐bodied strain were deprived of food on alternate days from 15 to 46 d of age.

2. Hyperphagia, amounting to twice the intake of control birds early in the experiment, occurred on the repletion day.

3. Final body weight attained 80% of that of the controls.

4. Body fat concentration decreased at first but returned to that of controls after 3 weeks.

5. A consistent hyperlipaemia was observed after food deprivation or restoration.

6. There was a marked increase in the digestive enzymes found in the small intestine, but not in the pancreas during the repletion day.

7. These responses may be considered as mechanisms to reduce the physiological manifestations of starvation.     

Response of three class‐IV major histocompatability complex haplotypes to Eimeria acervulina in meat‐type chickens

1. The importance of MHC genes and background genes in controlling disease resistance, including resistance to avian coccidiosis, has not been clarified in meat‐type chickens.

2. The role of class IV MHC genes in resistance to Eimeria acervulina was assessed in F2 progeny of a cross between 2 meat‐type lines, selected divergently for immune response to Escherichia coli.

3. Disease susceptibility was assessed by lesion score, body weight, packed cell volume and carotene absorption.

4. Chickens with the “K” class IV MHC haplotype had lower lesion scores than chickens with “F” and “A” haplotypes.

5. Plasma carotene concentrations were higher in chickens with “K” haplotype and lower in chickens with “F” and “A” haplotypes whereas body weight and packed cell volume were less sensitive measures of Eimeria infection.

6. Eimeria acervulina resistance appears to be associated with MHC class IV genes; information about MHC haplotypes may be useful in selecting for increased resistance of meat‐type chickens to coccidiosis.     

Yield and composition of raw and cooked meat of small white turkeys as influenced by dietary nutrient density and energy to protein ratio

1. Raw and cooked meat yields and the dry matter and fat contents of meat samples were determined on 144 carcases of Small White turkeys fed on diets that varied in nutrient density (ND) and energy to protein ratio (E:P).

2. High ND diets increased body weights, eviscerated carcase weights, relative carcase yields and carcase skin yield, but not breast or total meat yields.

3. Feeding a low ND diet to 6 weeks followed by diets with progressively increasing ND yielded performance and carcases with qualities comparable to feeding diets of constant medium or high ND; consequently cost savings could be made.

4. Increasing E:Ps reduced body weights, eviscerated carcase weights and carcase yields. Breast and total meat yields from male but not female carcases, and skin yield of female but not male carcases decreased with higher E:Ps.

5. The fat contents of breast and thigh meat samples increased with ND. The fat content of breast but not thigh meat decreased with higher E:P. Dry matter contents of meat samples did not vary consistently with changes in fat content.     

Comparative development of digestive organs,intestinal disaccharidases and some blood metabolites in broiler and layer‐type chicks after hatching

1. Body weight, digestive organ weights, and activities of disaccharidases (maltase and saccharase) activities were determined from day of hatch to 21 d of age in meat‐ and egg‐type chickens. Blood plasma was analysed for enzyme activities and metabolite concentration.

2. In meat‐type chickens food intake and growth rate were about 3‐fold those in egg‐type chickens. Food efficiency was superior in meat‐type chickens throughout the experimental period.

3. Meat‐type chickens hatched with disaccharidase activities exceeding those found in their egg‐type counterparts 2‐ to 5‐fold. From 7 d of age on, this trend reversed, i.e. activity was much higher in egg‐type than in meat‐type chickens.

4. Blood plasma amylase activity increased gradually in meat‐type chickens and was higher than in egg‐type chickens to 14 d of age. No breed differences were observed for alkaline phosphatase or lactate dehydrogenase activities during the experimental period.

5. Blood plasma concentrations of total protein, albumin, glucose, and calcium, were lower in meat than in egg‐type chickens.     

Replacement of maize by triticale in broiler diets

1. The nitrogen‐corrected metabolisable energy contents of the triticale varieties Multi Graze, Graze Grain 70, 204 and 131 were 12.28, 12.69, 12.37 and 12.03 MJ/kg respectively.

2. Increasing proportions (0, 25, 50 or 75%) of the maize of a diet were replaced by triticale 131 to provide diets of equal energy and nitrogen contents for broilers. These diets resulted in weight gains of 1.775, 1.782, 1.713 and 1.808 kg respectively at 8 weeks and there were no significant differences among efficiencies of food conversions.

3. Dressed carcass weights as percentages of body weight were 74.38, 75.01, 73.98 and 74.50 respectively and did not differ significantly.

4. Triticale in the diet did not seem to influence the relative weights of either liver or gizzard.

5. The flavour of the meat seemed to become less acceptable as the triticale in the diet increased but there were no significant differences in tenderness and juiciness of the meat caused by the treatments.     

Occurrence of pale soft exudative meat in mature turkey hens

1. Colour distribution of mature turkey hen breast meat was evaluated during the year in 7 commercial flocks (100 samples/flock) to assess the occurrence of the pale soft and exudative (PSE) problem. Evaluation was done on the processing line 24 h post mortem.

2. In addition, 10 selected samples/flock were analysed for pH, water holding capacity (WHC), and texture. The average L* value (lightness) was 48.9 with a variance of 15.3, skewness of 0.16, and kurtosis of 0.17. Minimum and maximum L* values recorded during die study were 37.7 and 58.5, respectively.

3. The pH ranged from 5.68 to 6.64 (mean 5.96), WHC ranged from 7 to 102% (mean 41%), and gel strength for the cooked samples ranged from 30 to 54 N (mean 44N).

4. Correlations between colour and WHC indicated die potential use of a fast colour measurement to identify PSE meat.

5. Breast muscle samples with L*s52 exhibited poor WHC. When this value was used as a cut off point for identifying PSE meat, die lowest incident observed was 5% and the highest was 40%.     

Effects of short intermittent lighting on food consumption and performance of dwarf broiler breeders and progeny

1. Two hundred and sixty four dwarf broiler breeder hens were subjected to ad libitum or restricted feeding and to four lighting patterns: 15L (bright light):9D (dark), 15L:9d (dim light), 2L:10d: 1L:11d, (0.5L:3.5d) × 6.

2. Breeder hens fed ad libitum and subjected to either conventional or intermittent lighting ingested respectively, 25 g and 14 to 17 g more than hens restricted to 115 g/d.

3. Body weight was greater in hens fed ad libitum irrespective of the lighting pattern and of the amount of food intake.

4. Persistency of egg production was impaired by intermittent lighting.

5. Ad libitum feeding reduced egg fertility. The decrease was larger in breeder hens on intermittent lighting.

6. Hatchability was increased in hens submitted to the symmetrical lighting pattern (0.5L:3.5d).

7. Egg and chick weights were higher in hens fed ad libitum.

8. Shell index and shell breaking strength increased in restricted hens on the intermittent lighting pattern (0.5L:3.5d) × 6.

9. The best performance was obtained in restricted hens on the conventional lighting pattern.     

Microbial status of chicken portions and portioning equipment

1. The sources and numbers of microbes contaminating poultry portions, which form an increasing proportion of poultry meat production were investigated. Total aerobic count at 30°C, pseudomonads, coliforms, enterococci and Staphylococcus aureus were enumerated.

2. Samples which had undergone different degrees of portioning, from whole birds to individual retail portions of poultry meat, were collected at points along the portioning line. Equipment surfaces, utensils and hands/gloves of factory personnel were examined.

3. In general, microbial numbers on carcase sampling sites were related to ‘exposure factor’, that is, the length of time the site was exposed to potential contamination during processing and portioning.

4. When results for individual sampling sites were analysed separately, no significant differences were found between sites on whole birds and the corresponding half bird sample sites. Comparison of numbers on half birds and on portions revealed a more variable situation.

5. Sites touched by rubber gloves when carcases were hung on the automatic portioning lines had greater contamination than other sites.

6. Provided factory and operative hygiene standards are high, portioning does not significantly increase numbers of microorganisms.     

Haematology and blood composition at two ambient temperatures in genetically fat and lean adult broiler breeder females fed ad libitum or restricted throughout life

1. Genetically fat and lean adult broiler breeder females were fed ad libitum or restricted throughout life. At one year of age, comparisons of blood viscosity and haematology and changes in blood chemistry after exposure to thermal stress were conducted.

2. Whole blood viscosity was more than twice as high, and plasma triglyc‐eride and haemoglobin concentrations were over 30% higher in fat line than in lean line females fed ad libitum or in restricted birds of both genotypes.

3. Mean cell haemoglobin concentration was higher and mean cell volume lower in fat compared with lean line females.

4. Food restriction was associated with lower plasma triglyceride concentrations, lower numbers of heterophils and monocytes and a lower heterophil‐lymphocyte ratio.

5. Fat line birds had a higher blood pCO₂ and lower pH than lean line birds.

6. Thermal stress was associated in ad libitum‐fed birds with a rise in blood pH and a decrease in pCO₂, and in restricted birds with a decline in blood pH and an increase in pCO₂.

7. Blood creatine kinase activity increased in all groups under thermal stress.