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PubMed2006

Dietary lysine needs of late-developing heavy broilers.

Two studies were conducted to determine the response of late-developing broiler males and females to dietary Lys from 42 to 56 d of age. Hubbard Ultra Yield males and females were placed at separated ends of a floor pen broiler house and raised on common diets. At 42 d of age, broilers were then fed 1 of 7 gradient concentrations of dietary Lys that progressively increased by 0.07% from 0.68 to 1.10% total Lys. Regression analysis was performed to estimate dietary Lys needs in the presence of quadratic responses. Female broilers did not respond to dietary Lys for any variable measured. Gradient additions of Lys improved feed conversion linearly (P < 0.01) for male broilers. Fillet weight, tender weight, and their composite increased linearly (P < 0.05) with Lys supplementation in male broilers. Quadratic responses were exhibited by carcass yield, fillet yield, and total breast meat yield, resulting in total Lys optimization dietary levels of 0.88, 0.93, and 0.93%, respectively, in male broilers. Based on results from this study, high-yield male broilers should be fed a minimum of 0.93% total dietary Lys (0.85% calculated digestible) from 42 to 56 d of age. Lack of response by female broilers suggests that less dietary Lys may be needed for adequate growth and meat yield.

Animal Nutritional Physiological Phenomena↗

PubMed2006

Variation in the pulmonary hypertensive responsiveness of broilers to lipopolysaccharide and innate variation in nitric oxide production by mononuclear cells.

Variability among broilers in their pulmonary hypertensive (PH) responsiveness to lipopolysaccharide (LPS) appears to reflect innate variation in the types or proportions of vasodilators and vasoconstrictors released by leukocytes and endothelial cells. Two experiments were designed to evaluate possible correlations between the PH responsiveness to LPS in vivo and the quantities of nitric oxide (NO; a potent pulmonary vasodilator) produced by mononuclear cells in vitro. In Experiment 1, blood samples were collected from male broilers from a base population (control group) and from survivors of a 60% lethal dose i.v. injection of cellulose microparticles (MP survivor group). In Experiment 2, blood samples were collected from male broilers from a relaxed line and from lines known to be susceptible or resistant to pulmonary hypertension syndrome. Peripheral mononuclear cells (PMNC) from each blood sample were cultured at 2 million cells per well, remained unstimulated, or were stimulated with LPS to elicit the expression of inducible NO synthase, and the 24-h production of NO was measured. In both experiments, unstimulated PMNC cultures did not produce consistently detectable levels of NO, whereas LPS-stimulated cultures produced quantities of NO that varied widely among individuals. Nitric oxide production by cultured PMNC also was evaluated by flow cytometry, demonstrating that LPS-stimulated PMNC produced substantially more NO than did unstimulated cells in all of the groups evaluated. Moreover, NO-producing PMNC were identified to be monocytes. The same broilers from which PMNC had been isolated were catheterized subsequently to record pulmonary arterial pressure, LPS was injected i.v. to assess the amplitudes of peak and postpeak PH responses, then N(omega)-nitro-L-arginine methyl ester was injected to inhibit ongoing NO production. In Experiment 1, the amplitude of the peak and postpeak PH responses to LPS were correlated with the quantity of NO produced by LPS-stimulated cultured PMNC from broilers in the control group but not for MP survivors. In Experiment 2, the postpeak PH response to LPS was correlated with the quantity of NO produced by LPS-stimulated PMNC from broilers in the relaxed line, but not in the susceptible or resistant lines. In all groups, N(omega)-nitro-L-arginine methyl ester injections triggered substantial increases in pulmonary arterial pressure (> or = 8 mm Hg), thereby revealing a significant ongoing modulation by NO of the PH response to LPS. We concluded that most of the modulatory NO generated in vivo during the acute PH response to LPS (within 60 min postinjection) likely is produced by constitutive NO synthase in the vascular endothelium. In addition, the NO produced by inducible NO synthase in PMNC appeared to have modulated the LPS-stimulated PH responses of unselected broilers having the broadest range of pulmonary vascular capacities (control broilers and relaxed line), but not in broilers whose pulmonary vascular capacities had been selected to represent the higher (MP survivors, resistant line) or lower (susceptible line) extremes of the population.

Animals↗

PubMed2006

Influences of feeding conventional and semisynthetic diets and transport of broilers on weight gain, digestive tract mass, and plasma hormone and metabolite concentrations.

Two replicate experiments were done to investigate if special diets provided to broilers in their last phase of life could reduce the negative effects of feed withdrawal and transport without an increased content of the digestive tract. In each experiment, 240 broilers were used. The experiments consisted of 2 interventions: the feed intervention and the transport intervention. The feed intervention took 72 h, in which broilers had full access to a conventional grower diet, a conventional grower diet with an increased carbohydrate level, a conventional grower diet with an increased fat level, a semisynthetic diet, or a semisynthetic diet with an increased carbohydrate level. The diets differed remarkably in carbohydrate content; carbohydrate content was approximately 67% in the semisynthetic diets and 42%, on average, in the conventional diets. Moreover, all of the carbohydrates in semisynthetic diets were highly soluble and digestible. The diets were compared with a feed withdrawal period of 24 h before transport. The transport intervention took 3 h; broilers were caught, crated, loaded, transported for 1.5 h, and had to wait in the crates for 1 h thereafter; or remained in the pens. After the transport intervention, blood samples were taken to determine plasma corticosterone, triiodothyronine, glucose, lactate, uric acid, nonesterified fatty acid, and triglyceride concentrations. Also, changes in live weight (LW) and digestive tract mass were assessed. The LW losses of broilers fed with semisynthetic diets after transport were 0.24% per hour less than of feed-withdrawn broilers. Moreover, intake of semisynthetic diets was approximately 200 g, whereas the intake of conventional diets was approximately 300 g. Therefore, the digestive tract mass as a percentage of LW was lower for semisynthetic-fed broilers in comparison with conventional-fed broilers, which can lead to a lesser degree of contamination during evisceration. No increase of corticosterone was found due to transport in semisynthetic-fed broilers. Semisynthetic feed with high carbohydrate concentration could be a good alternative for the feed withdrawal period held before transportation to the processing plant.

Animal Feed↗

PubMed2006

Genetic diversity and description of transmission routes for Campylobacter on broiler farms by amplified-fragment length polymorphism.

AIMS: To investigate the genetic diversity of Campylobacter in broilers and in the environment of broiler farms, to compare the genetic profiles and describe critical factors for transmission to broilers. METHODS AND RESULTS: Flocks at three of four investigated farms became colonized with Campylobacter. The total proportion of Campylobacter-positive samples at different farms varied from 20% to 42%. The farm with the poorest biosecurity routines had broilers that became infected earliest, the highest proportion of positive samples and the highest genetic diversity among the broiler Campylobacter isolates. Campylobacter isolates within common amplified-fragment length polymorphism (AFLP) clusters (95-100%) were found to be present in outdoor environment and in broilers at adjacent farms before they were found in the broilers. A large presence of Campylobacter in the farm environment was demonstrated after the broilers were infected. A high genetic diversity was found among Campylobacter present in the outdoor environment, where certain Campylobacter clusters were found for periods of up to 6 weeks. CONCLUSION: Confirmation by AFLP indicates adjacent poultry farms and outdoor environment as major sources of Campylobacter infection of broilers, this being the novel achievements. SIGNIFICANCE AND IMPACT OF THE STUDY: The results provide more exact knowledge on transmission of Campylobacter at farm level, helpful for developing optimal preventive strategies.

Animal Husbandry↗

PubMedDate not supplied

The role of litter beetles as potential reservoir for Salmonella enterica and thermophilic Campylobacter spp. between broiler flocks.

We evaluated the role of beetles infesting broiler chicken rearing facilities as potential reservoirs for Salmonella enterica infections between successive broiler flocks. In addition, their role as potential reservoirs for thermophilic Campylobacter spp. was also investigated. Fourteen broiler houses located at 11 different farms were included in the study. The houses were nonrandomly selected on the basis of their salmonella status; nine were persistently contaminated with salmonella whereas five were salmonella negative. For each broiler house, two consecutive broiler flocks (i.e., 28 broiler flocks in all) as well as beetles collected during both rotations of production and in the empty period (after cleaning and disinfection) between these flocks were monitored for the presence of salmonella. Examinations for the presence of campylobacter in the same sample materials were also performed. Beetles sampled during production were positive for salmonella or campylobacter or both. Furthermore, in one house, the occurrence of Salmonella indiana in two consecutive broiler flocks coincided with the presence of S. indiana-contaminated beetles in the empty period between the flocks. The genotype of the identified S. indiana was in all cases identical when analyzed by pulsed-field gel electrophoresis. However, our results also suggest that salmonella from beetles may not always be transmitted to the chickens and that beetles living in contaminated houses can remain free of infection. All cases of campylobacter-positive beetle samples were detected in connection with a positive chicken flock; in no case was campylobacter isolated from beetles taken from the empty period between rotations. Four beetle species were identified during this study. Alphitobius diaperinus was found in all houses and was relatively abundant in most. Typhaea stercorea and Ahasverus advena were found in eight and nine houses, respectively, and were abundant in most of these. Carcinops pumilio was found in small numbers in eight houses. No other insect species was identified. These investigations have shown that beetles in broiler houses infrequently are positive for salmonella. However, transmission of S. indiana between two consecutive broiler flocks can coincide with the presence of salmonella-contaminated beetles in the empty period, indicating that the beetles were the reservoir of S. indiana between the two flocks. Concerning campylobacter, the results suggest that beetles do not play a significant role as a reservoir of campylobacter from one rotation to the next.

Animal Husbandry↗

PubMedDate not supplied

Prevalence of antibodies against Ornithobacterium rhinotracheale in broilers and breeders in Southern Brazil.

In this investigation, we determined the prevalence of the Ornithobacerium rhinotracheale (ORT) infection in broilers and broiler breeders in southern Brazil. We also correlated the presence of antibodies in broilers with performance. Sera from 1550 broilers from 50 flocks were collected during the slaughter time in nine companies with federal veterinary inspection of the state of Rio Grande do Sul. Sera from 480 meat-type breeders of 40 flocks from 14 companies in southern Brazil were also analyzed by enzyme-linked immunosorbent assay, and the prevalence of antibodies was determined. The prevalence of ORT antibodies in broiler flocks was 63.83%, but in each individual flock only 6.52% of the birds were positive. The prevalence in broiler breeder flocks was 100.00%, and in each individual flock 94.62% of the birds were positive. There was a positive correlation between the presence of antibodies to ORT and decreased body weight in broilers. There was no significant correlation between presence of antibodies to ORT and age, lineage, efficiency index, feed conversion, and mortality. There was a positive correlation between the presence of respiratory signs and antibodies to ORT, although the reverse correlation was not significant. These results confirm that ORT is present and widespread in broilers and broiler breeders in southern Brazil.

Animals↗

PubMed2004

Rice mill feed as a replacement for broiler litter in diets for growing beef cattle.

The efficacy of replacing broiler litter with rice mill feed was evaluated in four experiments. In Exp. 1, 40 predominantly Angus steers (initial BW = 277+/-18.2 kg) were fed four dietary treatments for 112 d (five steers per pen; two pens per diet). Dietary treatments (DM basis) were as follows: 1) 47% broiler litter:53% corn; 2) 60% rice mill feed:40% corn; 3) 50% rice mill feed:50% corn; and 4) 40% rice mill feed:60% corn. All diets, along with bermudagrass hay, were fed free choice. Daily gains were faster (P < 0.10) for the 50:50 and 40:60 diets (1.26 and 1.30 kg/d, respectively) than for the broiler litter diet (0.89 kg/d). Daily DMI was less (P < 0.10) by steers consuming rice mill feed-based diets than by those consuming broiler litter-based diets. In Exp. 2, 16 Angus x Charolais steers (initial BW = 277+/-22.7 kg) were fed the same four diets used in Exp. 1 while housed in individual metabolism stalls for determination of nutrient digestibility. Daily DMI was not different (P > 0.10) among diets. Nutrient digestibilities did not differ among diets (P > 0.10). In Exp. 3, 40 Continental cross steers (initial BW = 257+/-21.3 kg) were fed one of four dietary treatments for 112 d (five steers per pen; two pens per diet). On a DM basis, diets were as follows: 1) 47% broiler litter:53% soyhulls; 2) 70% rice mill feed:30% soyhulls; 3) 60% rice mill feed:40% soyhulls; and 4) 50% rice mill feed:50% soyhulls. All diets, along with bermudagrass hay, were fed free choice. Daily gains were less (P < 0.05) for the broiler litter diet than for the 60:40 and 50:50 diets (1.05, 1.16, and 1.28 kg/d, respectively), and steers fed the broiler litter diet consumed less DM than did steers fed the varying rice mill feed-based diets (P < 0.10). In Exp. 4, 16 Angus x Charolais steers (initial BW = 292+/-21.1 kg) were fed the same four diets as in Exp. 3 while housed in individual metabolism stalls for determination of nutrient digestibility. Daily DMI was less (P < 0.01) for the broiler litter diet (5.0 kg/d) than for the 70:30, 60:40, and 50:50 diets (7.8, 7.9, and 7.9 kg/ d, respectively). Digestibilities for DM, OM, and ADF did not differ (P > 0.10) among treatments; however, CP digestibility was greatest (P < 0.10) for the 60:40 diet, and NDF digestibility was least (P < 0.10) for the 70:30 diet. Rice mill feed can be used to replace broiler litter to formulate low-cost diets for stocker calves. Soyhulls and corn can be blended with rice mill feed to produce acceptable backgrounding diets for growing beef calves.

Animal Feed↗

PubMed1976

Manganese levels and the morphology of the epiphyseal plate in broilers with slipped tendons.

Manganese deficiency in chickens results in perosis and a higher incidence of slipped tendon. Perosis is associated with a disorganization of the epiphyseal growth plates and changes in the chemical composition of the cartilage matrix. Male broilers with slipped tendons were selected from a commercial broiler farm over a 9 week growing period. Their growth rates, epiphyseal cartilage histology and tissue manganese concentrations were examined and compared with (a) normal broilers from the same farm, and (b) similar broilers raised on control and manganese deficient diets. Field broilers with slipped tendons showed no evidence of abnormality in the histological appearance of the proximal tibial growth plate at any of the ages examined. The manganese content of liver and epiphyseal cartilage from field broilers showing slipped tendon was comparable with that present in tissue from normal broilers wither from the field or raised on a chemically defined diey supplemented with managese. The slightly retared growth rate seen in the field broilers was attributed to feeding problems associated with the lameness condition. These results provide conclusive evidence that slipped tendon in field broilers is not dur to a manganese deficiency in the tissues, nor does it appear to be associated with abnormal proliferation of the chondrocytes in the epiphyseal plate.

Animals↗

PubMed1982

Dietary energy requirements of broilers reared in low and moderate environmental temperatures. 1. Adjusting dietary energy to compensate for abnormal environmental temperatures.

Four trials were conducted to determine the feasibility of replacing fossil fuel energy with dietary energy to meet the 23- to 48-day-old broiler chicken's energy requirements during abnormal cold exposure. Sexed broilers were fed 3250 or 3500 kcal metabolizable energy (ME)/kg in a 21.1 C environment (a normal management situation), and 3250 or 3125 kal ME/kg in a 26.7 C environment. Body weights and feed utilizations increased when broilers were exposed to a 15.6 C environmental temperature and fed 3375 kcal ME/kg dietary energy as compared to feeding a 3250 kcal ME/kg dietary energy in the same environment. When broilers were reared in a 10.0 C environment, maximum body weights were not obtained by increasing the dietary energy from 3250 to 3500 kcal/kg dietary energy. Broiler males, fed 3250 kcal ME/kg and reared in either a 21.1 or a 26.7 C environment, were larger than males reared in 10.0 C environment. No significant differences were found in broiler female weights reared in a 10.0, 15.6, or 21.1 C environment and fed 3250 kcal ME/kg in each temperature regimen. Feed utilizations were the same broilers were reared in a 15.6 C environment and fed 3375 kcal ME/kg compared to broilers reared in a 21.1 C environment and fed 3250 kcal ME/kg. These results indicate that maximum performance of 23- to 48-day-old broilers may be achieved in a 15.6 C environment by feeding a high energy diet (3375 kcal/kg). Results also showed that dietary energy may replace fossil fuel energy that would normally be supplied in a 21.1 C environment.

Adipose Tissue↗

PubMed1983

Long-term broiler performance with bambermycins and bambermycins plus roxarsone.

Bambermycins and bambermycins plus roxarsone were fed to broilers in ten consecutive experiments to determine if response (measured by body weight and feed efficiency) was continuous over a long term. Bambermycins was added at 1.1 ppm (1 to 44 days) and 2.2 ppm (45 to 51 days) to both test rations. In addition, one test ration contained roxarsone (3-nitro-4-hydroxyphenylarsonic acid) at 50 ppm (1 to 44 days). Each experiment was conducted with 1,080 commercial broiler cross-run chickens. Broilers fed bambermycins and bambermycins plus roxarsone were heavier (P less than .05) than controls in every experiment. Bambermycins plus roxarsone treated broilers were heavier (P less than .05) than bambermycins treated broilers in 2 out of 10 experiments. Broilers fed bambermycins converted feed more efficiently (P less than .05) than controls in 6 of 10 experiments and were more efficient (P less than .05) than bambermycins plus roxarsone fed broilers in 1 of 10 experiments. Bambermycins plus roxarsone treated broilers were more efficient (P less than .05) than controls in 5 of 10 experiments. These findings indicate that over a long term bambermycins and bambermycins plus roxarsone consistently and significantly (P less than .05) increased broiler body weights over controls, although the addition of roxarsone was not always effective in increasing body weights or improving feed efficiency over bambermycins fed alone.

Animals↗

PubMed1992

Maternal body weight and feed allowance of breeders affect performance of dwarf broiler breeders and tibial ossification of their progeny.

Four hundred and eight dwarf broiler breeder hens were raised collectively in a floor pen to 21 wk of age. At this age they were classified into four groups with reference to their individual BW as heavy (1.95 +/- .1 kg), medium (1.80 +/- .1 kg), light (1.69 +/- .1 kg), and ultralight (1.57 +/- .1 kg). All groups were individually caged at 23 wk of age. During the reproductive period, each group was divided into three subgroups fed on liberal, intermediate, or severe feed restriction (reaching up to 135, 125, and 115 g of daily feed allowance at 29 wk of age, respectively). Intergroup differences in BW were maintained throughout the experiment (21 to 61 wk) but tended to decrease with age. Hen-day egg production was depressed by the lower feed allowance. Fertility and hatchability were impaired when hens received the largest quantities of food. Hen size influenced female breeder performance only slightly. Shell quality and albumen quality were affected by the level of feed consumption. Egg weights as well as BW of the progeny at hatching were enhanced by increased maternal BW and feed allowance. This positive maternal effect was still present at 40 days of age. Despite better overall BW performances of the male versus female broilers, the abdominal fat pad of female broilers was heavier than that of males and tended to increase with breeder size and breeder feed allowance. Accordingly, tibial breaking strength and percentage ash of the progeny at hatching were markedly improved in proportion to the breeders' BW and to their feed allowance. The effect of breeder size on broiler tibial quality was maintained up to 40 days of age but the effect of breeder feed intake tended to disappear with increasing age of the broilers. Tibial strength and mineralization were higher in male than in female broilers at 40 days of age. Dyschondroplasia was higher in broilers hatched from heavier breeder hens, but was not influenced by breeder feed intake. The incidence of varus and valgus in progeny was similar whatever the breeders' treatment. It is concluded that performance of dwarf breeders in a given flock depends mainly upon breeder feed allowance but that broiler performance and, especially, tibial ossification of broilers is greatly influenced by maternal size and, to a lesser extent, by maternal feed intake.

Animals↗

PubMed1992

Effect of early feed restriction on growth, feed conversion, and mortality in broiler chickens.

Two floor pen and two battery experiments were conducted to determine the effects of early feed restriction on the performance of commercial broilers. Feed restriction was induced in all experiments by providing chicks with 40 kcal of ME per bird per day, commencing at 4 days of age. Male chicks were feed-restricted for 7 (Experiments 1 and 2) or 6 days (Experiments 3 and 4), whereas broiler females were restricted for 5 days (Experiment 1). Ad libitum feeding was resumed after the restriction periods, and continued through the conclusion of the experiments at 49 (Experiments 1 and 2) or 28 (Experiments 3 and 4) days of age. Broilers provided ad libitum access to feed for the entire experimental period served as the controls in each study. Broilers subjected to an early feed restriction had significantly (p less than or equal to .05) lower mean body weights than controls for all ages measured in the four experiments. However, feed conversion ratios for restricted broilers were significantly lower at 28 (Experiments 1 through 4) and 49 (Experiments 1 and 2) days of age than for birds consuming feed ad libitum. Through regression analyses, it was estimated that male broilers in Experiments 1 and 2 would require approximately 2 additional days to obtain body weights similar to those observed in control broilers and would still maintain a lower feed conversion ratio at this older age. In Experiments 1 and 2, weekly body weight gains for restricted broilers were significantly lower than for controls from 0 through 28 days of age. However, restricted broilers (7 days) in Experiment 2 had significantly higher rates of gain from 29 to 49 days of age than unrestricted controls. Total pen body weights for restricted and ad libitum groups were similar at 49 days of age in Experiments 1 and 2, which reflected the significant difference in mortality observed between the two groups.

Age Factors↗

PubMed1994

The effect of beta-hydroxy-beta-methylbutyrate on growth, mortality, and carcass qualities of broiler chickens.

Experiments were conducted to determine whether the leucine catabolite beta-hydroxy-beta-methylbutyrate (HMB) could influence protein metabolism in broilers. In Experiment 1, HMB was fed at either .01 or .05% of the diet. beta-Hydroxy-beta-methylbutyrate did not improve feed conversion or BW gain; however, broilers fed HMB at .01% in a diet formulated to meet NRC (1984) recommendations had no mortality (P < .03) from 0 to 21 d of age. In Experiment 2, HMB fed at .003, .01, .03, and .09% of the diet had no significant affect on growth or carcass yield of the broilers when compared with control-fed broilers. In Experiment 3, HMB fed at .001, .003, and .01% of the diet had no effect on broiler growth. In Experiment 4, HMB was fed at .01% of the diet in combination with an antibiotic and coccidiostat (GP). Use of GP increased (P < .01) BW, feed conversion, and carcass yield when compared with the control broilers. In Experiment 5, HMB was fed at .1% of the diet, and effects of sex and GP were examined. beta-Hydroxy-beta-methylbutyrate decreased (P < .01) mortality by 72% in the male broilers. In a combined analysis, HMB fed at .01% of the diet (Experiments 1, 2, and 3) increased breast yield (P < .05) and reduced mortality by 56% (P < .04) from 0 to 21 d of age. In a combined analysis, HMB fed at .003% of the diet (Experiments 2 and 3) increased 42-d BW (P < .02) and hot (P < .04) and chilled (P < .05) carcass yields. In conclusion, across all HMB dosages mortality of male broilers was decreased from 6.37 to 4.39% (-31%, P < .04) by feeding HMB, with the pattern of death suggesting that HMB decreased the incidence of sudden death syndrome in these broilers.

Animal Feed↗

PubMedDate not supplied

Reovirus serology in broiler parents and their progeny and its correlation with performance.

An intensive vertically integrated monitoring program for broiler breeders and their offspring was set up in a Belgian poultry integration between 1993 and 1997. Serology for anti-reovirus antibodies was performed by enzyme-linked immunosorbent assay on blood samples taken from the broiler parents throughout rearing and production and also on blood samples taken at day-old and at slaughter from the broilers. Furthermore, production parameters of the birds were registered. All data were used two by two in a simple correlation study to calculate the degree to which these variables were linearly correlated. The reovirus antibody pattern indicated frequent field infections breaking through vaccinal immunity in the broiler parents. Under the epidemiologic conditions of this study, high antibody titers in the parents or in the broilers at day-old were significantly correlated with poor feed conversion, increased mortality, increased slaughterhouse condemnation, and low production score in the broilers. These correlations strongly support the view that reovirus infections can be economically important under European conditions of broiler production. Improvement of reovirus vaccines or the vaccination scheme in broiler parents or both may lead to better production results in the broiler offspring.

Animal Husbandry↗

PubMedDate not supplied

Body weight suppression in broilers naturally infected with avian leukosis virus subgroup J.

Broiler progeny were hatched from avian leukosis virus (ALV)-negative and ALV subgroup J (ALV-J)-positive breeders. ALV-J infection in progeny was identified by p27 antigen capture enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction specific for ALV-J performed on serum or plasma samples obtained at hatch. Hatch weights did not differ between ALV-negative broilers and ALV-J-positive broilers. Body weights of ALV-J-positive broilers were 64.4% of those of ALV-negative broilers at 1 wk of age. At 8 wk of age, weights of broilers with congenital ALV-J infection were still only 63.8% of those of ALV-negative broilers. No other concurrent pathogen was detected in either group of broilers. These findings indicate that congenital ALV-J infection is associated with significant weight suppression in broilers in the absence of other pathogens.

Animals↗

PubMedDate not supplied

Effects of reduction in floor space during crating on haematological indices in broilers.

In the perspective of animal protection and welfare, the most common and potentially the most frightening events encountered by the domestic fowl are procedures connected with transport. This study provides an evidence that reduction in floor space during crating, which is approximately 10% above requirements given to EEC Directives (accompanied with mixed social and heat stress due to high animal density), induces markedly elevated stress in broilers which is manifested by changes in haematological indices. The experiment was performed on ROSS 308 broilers (total number 70, mean body weight 3.05 kg). At 42 days of age, the broilers were crated for 2-hours either with reduction in floor space to 115 cm2/kg (S115) or 105 cm2/kg (S105) of body weight. The total erythrocyte and leukocyte count, haematocrit, haemoglobin, MCV (mean cell value), MCH (mean cell haemoglobin) and MCHC (mean cell haemoglobin concentration) values were monitored and differential leukocyte count was assessed 20 h following crating. When compared with uncrated control, S105 broilers exhibited highly significant increase in haemoglobin level, MCH and MCHC values, significant increase in MCV values and significant decrease in total erythrocyte count. S115 broilers did not manifest any significant changes in haematological parameters compared with control. When compared with S115 broilers, S105 broilers manifested significantly elevated haemoglobin level and MCV values, highly significantly elevated MCH and MCHC values and depressed erythrocyte count. It follows from results that the reduction in floor space to 115 cm2/kg for 2 hours did not induce any significant changes in both total and differential leukocyte counts in blood of broilers when compared with control chickens. However, reduction in floor space to 105 cm2/kg resulted in highly significant increase in heterophil counts and subsequently also HLR (heterophil/lymphocyte ratio) was significantly elevated. When compared S105 and S115 broilers, mean values of heterophil counts and HLR ratio were higher due to reduction in floor space to 105 cm2/kg. The differences, however, were not statistically significant.

Animal Welfare↗

PubMed2004

Effect of initial COD concentration, nutrient addition, temperature and microbial acclimation on anaerobic treatability of broiler and cattle manure.

In this study, anaerobic treatability and biogas generation potential of broiler and cattle manure were investigated. For this purpose, seven sets of anaerobic batch reactor experiments were performed using broiler and cattle manure and their mixtures in five different ratios (100% broiler; 75% broiler, 25% cattle; 50% broiler, 50% cattle; 25% broiler, 75% cattle; 100% cattle). These manure mixtures had two different initial chemical oxygen demand (COD) (12,000 and 53,500 mg/l) concentrations. The effects of initial COD concentration, nutrient and trace metal supplementation, microbial acclimation and digestion temperature were investigated. Results revealed that the efficiency of total COD removal was 32.0-43.3% and 37.9-50% for initial COD concentrations of 12,000 and 53,500 mg/l, respectively. The biogas yields observed for initial COD concentrations of 12,000 and 53,500 mg/l were 180-270 and 223-368 ml gas/g COD added, respectively. A decrease in biogas yield was observed as the fraction of broiler manure increased in mixture of broiler and cattle manure at initial COD values of 53,500 mg/l.

Acclimatization↗

PubMed2002

Cellular immune response in the small intestine of two broiler chicken lines orally inoculated with malabsorption syndrome homogenates.

We studied the cellular immune response against malabsorption syndrome (MAS) in two broiler chicken lines, A and B. We determined the number of pan T-lymphocytes (CD3), helper T-lymphocytes (CD4), cytotoxic T-lymphocytes (CD8) and macrophages/monocytes in the small intestine in the first 2 weeks after oral inoculation of two MAS homogenates, MAS80 and MAS97-1. The immune cells were detected on cryostat tissue by immunohistochemistry and counted by villus area. In trial 1, we compared the two broiler lines for weight gain depression, intestinal lesion and number of CD3, CD4, CD8 cells and macrophages/monocytes after MAS80 inoculation. Although there was no significant difference in weight gain depression between the two broiler lines, line B had significantly higher numbers of CD8+ T-cells per villus area than had line A. To confirm part of the results of trial 1, trial 2 was done in which we compared different homogenates in broiler line B. Broiler line B was orally inoculated with either MAS97-1, intestinal homogenate obtained from healthy chickens (healthy homogenate), or phosphate buffered saline (PBS). In this trial, the MAS97-1 homogenate also induced weight gain depression and intestinal lesions, whereas the "healthy homogenate" and PBS did not induce weight gain depression or intestinal lesions. The broilers inoculated with MAS97-1 homogenate had significantly more CD8+ T-cells per villus area than had broilers inoculated with "healthy homogenate" or PBS. Increased CD8+ T-cells per villus area in the affected small intestines of broilers suggests an increase of cytotoxic T-cell activity.

Animals↗