Use In Broilers Research Articles

Residue depletion of enrofloxacin and flumequine in feathers of broilers based on quantitative UHPLC-MS/MS detection

To explore potential factors contributing to high fluoroquinolone resistance levels, it is essential to develop analytical methods capable of detecting residues and trace amounts of antibiotic use in broilers. The aim of the present study was to develop and in-house validate a sensitive UHPLC-MS/MS method capable of determining enrofloxacin (ENR) and flumequine (FLU) residues at slaughter age (day 45) when the animals were treated with these antimicrobials one day after hatching. Residue depletion of ENR and FLU in feathers was also assessed. Two experimental trials were performed, both consisting of 5 different treatment groups. In the first trial animals were treated with ENR and in the second one with FLU. The developed method was successfully validated and was found to be sensitive enough to detect residues of fluoroquinolones in the feathers up until slaughter age in all treatment groups. Average ENR concentration on day 45 was 10 ng g−1 feather after drinking water treatment, with all concentrations above the limit of quantification (LOQ) of 5 ng g−1 feather. For FLU average concentration on day 45 after drinking water administration was 4 ng g−1 feather, with an LOQ of 1 ng g−1 feather. Therefore, the method is suited for application to monitor fluoroquinolone use in broilers.

Effects of a novel synbiotics-enzyme complex as a replacement for antibiotics on growth performance, slaughter and meat characteristics, immune organ index, and intestinal morphology of broilers.

Antibiotic use in broilers is being discouraged globally due to the challenges it poses. This study was conducted to assess the effects of supplementing broilers with a Symbiotic-Enzyme complex (SEC) containing prebiotics (mannose oligosaccharides), probiotics (Clostridium butyricum and Bacillus subtilis), and enzymes (glucose oxidase, and α-galactosidase) as an alternative to antibiotics on growth performance, carcass and meat quality traits, mortality, linear body measurements, intestinal morphology and immune organ indexes. A total of 864 mixed-sex 1-day-old arbor acres (AA+) broilers were allocated to 8 experimental groups replicated 9 times with 12 chickens per replicate. These included 6 treatment groups with SEC inclusion levels of 0.025, 0.04, 0.05, 0.06, 0.08, and 0.10%, respectively, and two control groups: a negative control group containing a basal diet only and the positive control group (Antibiotics group) containing a basal diet and antibiotic oxytetracycline added at 0.2%. Growth performance was measured on day 21 and 42, and the mortality, carcass, meat quality traits, linear body measurements, intestinal morphology, and organ size indexes were measured on day 42. The results indicated that supplementing broilers with 0.1% SEC resulted in insignificant (P > 0.05) increases in average daily feed intake (ADFI), significant (P < 0.05) increases in the average daily gains (ADG), and significant (P < 0.05) reduction in a feed-to-gain ratio (F/G) in all the phases compared to the control and antibiotics groups. Supplementation of broilers with 0.1% SEC inclusion levels also significantly (P < 0.05) increased the body slope length, chest width, chest depth, keel length, and shank circumference. Furthermore, broilers on diets containing 0.1% SEC inclusion level also had significantly (P < 0.05) higher dressed, semi-evisceration, evisceration, and breast muscle percentages. Including SEC at 0.1% also significantly (P < 0.05) increased villus height and villus-to-crypt ratio (V/C) but reduced crypt depth in the duodenum, jejunum, and ileum compared to the control groups. SEC inclusion at 0.1% significantly (P < 0.05) increased the spleen, bursal, and thymus indexes, respectively. Supplementation of broilers with 0.1% SEC can be used as an antibiotic alternative because it increases the F/G, improves the carcass and meat quality, increases the body conformation, improves the small intestines' functions, and immune organ size.

Effects of probiotic supplementation on broiler growth performance: a meta-analysis of randomised controlled trials

Context The effects of probiotics on broilers’ growth and productivity performance have been reported in many scientific studies, and different results have been found. Aim This study aimed to assess the effects of probiotics on broiler growth performance via meta-analysis. Methods In this study, the PubMed database was searched with the keywords ‘broiler’ and ‘probiotic’ and it was determined that 60 of 605 studies were suitable. Average daily gain and feed conversion ratio were used as performance parameters. Publication bias was evaluated with Egger’s and Begg’s tests. The trim and fill method was applied when even one of these tests was significant. Heterogeneity among studies was assessed using the Cochran Q test. The random-effect model was used to estimate effect sizes if heterogeneity was statistically significant; otherwise, the fixed-effect model was used. In addition to evaluating all studies, subgroup analyses were performed depending on study duration, probiotic strain, and the probiotic content. Key results According to the meta-analysis results, there was a significant difference between the probiotic and control groups in studies lasting 35 days in terms of average daily gain (P = 0.005) and feed conversion ratio (P = 0.002). But only the average daily gain (P &lt; 0.001) value was different between the groups in studies lasting 42 days. According to the probiotic strain, significant differences were found between the probiotic and control groups in terms of both growth parameters examined in studies using mono-strain and multi-strain probiotics. A significant difference was found between the probiotic and control groups in average daily gain values in studies where probiotics containing lactic acid bacteria (LAB) and clostridia were used. Conclusion In conclusion, this study is a current research that examined the effects of probiotic use in broilers in detail according to more than one factor. Implication In this study, articles in the PubMed database were examined. The sample size of the study can be increased by scanning other databases with the same keywords.

Seeing is caring – automated assessment of resource use of broilers with computer vision techniques

Routine monitoring of broiler chickens provides insights in the welfare status of a flock, helps to guarantee minimum defined levels of animal welfare and assists farmers in taking remedial measures at an early stage. Computer vision techniques offer exciting potential for routine and automated assessment of broiler welfare, providing an objective and biosecure alternative to the current more subjective and time-consuming methods. However, the current state-of-the-art computer vision solutions for assessing broiler welfare are not sufficient to allow the transition to fully automated monitoring in a commercial environment. Therefore, the aim of this study was to investigate the potential of computer vision algorithms for detection and resource use monitoring of broilers housed in both experimental and commercial settings, while also assessing the potential for scalability and resource-efficient implementation of such solutions. This study used a combination of detection and resource use monitoring methods, where broilers were first detected using Mask R-CNN and were then assigned to a specific resource zone using zone-based classifiers. Three detection models were proposed using different annotation datasets: model A with annotated broilers from a research facility, model B with annotated broilers from a commercial farm, and model A+B where annotations from both environments were combined. The algorithms developed for individual broiler detection performed well for both the research facility (model A, F1 score &amp;gt; 0.99) and commercial farm (model A+B, F1 score &amp;gt; 0.83) test data with an intersection over union of 0.75. The subsequent monitoring of resource use at the commercial farm using model A+B for broiler detection, also performed very well for the feeders, bale and perch (F1 score &amp;gt; 0.93), but not for the drinkers (F1 score = 0.28), which was likely caused by our evaluation method. Thus, the algorithms used in this study are a first step to measure resource use automatically in commercial application and allow detection of a large number of individual animals in a non-invasive manner. From location data of every frame, resource use can be calculated. Ultimately, the broiler detection and resource use monitoring might further be used to assess broiler welfare.

The effects of lactic acid bacteria and yeasts as probiotics on the growth performance, relative organ weight, blood parameters, and immune responses of broiler: A meta-analysis.

Introduction: The number of publications in Scopus on this topic increased from less than 50 in 1995 to more than 250 in 2015. In other hand, inconsistency in results about the correlation between yeast and lactic acid bacteria as probiotics has been evident since the early publications on use in broilers. Methods: A meta-analysis was conducted to determine relationship between lactic acid bacteria and yeast as probiotics to broiler diets on the growth performance, relative organ weight, blood parameters, and immune response of the broiler. A database was designed based on published data that reported the use of probiotics on the broiler. The method used for selecting articles was based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) method. Articles selected were taken from PubMed, Web of science, Scopus, Google Scholar, and Science direct databases as well as individual. Results: The final database consists of 49 in vivo articles, 93 studies, and 225 treatments. The analysis statement in the system was a PROC MIXED procedure of SAS software. The level of probiotic increased (p <0.001) body weight, body weight gain, and feed intake of broiler. There was a reduction (p <0.01) on feed conversion ratio and mortality on the level probiotic given to broiler. Supplementation of probiotics in broiler diet increased (p <0.001) the weight of liver, spleen, gizzard, bursa of fabricius and carcass yield, while reduced (p<0.001) abdominal fat weight. The probiotic given increased the total of red and white blood cells (both at p < 0.001) but did not affect lymphocyte. Discussion: It can be concluded the yeast act as supporting agent that serves lactic acid bacteria as probiotic increases the growth performance, relative organ weight, blood parameters, and immune response of the broiler.

A Novel Approach against Salmonella: A Review of Polymeric Nanoparticle Vaccines for Broilers and Layers.

This work discusses the present-day limitations of current commercial Salmonella vaccines for broilers and layers and explores a novel approach towards poultry vaccination using biodegradable nanoparticle vaccines against Salmonella. With the increasing global population and poultry production and consumption, Salmonella is a potential health risk for humans. The oral administration of killed or inactivated vaccines would provide a better alternative to the currently commercially available Salmonella vaccines for poultry. However, there are currently no commercial oral killed-vaccines against Salmonella for use in broilers or layers. There is a need for novel and effective interventions in the poultry industry. Polymeric nanoparticles could give way to an effective mass-administered mucosal vaccination method for Salmonella. The scope of this work is limited to polymeric nanoparticles against Salmonella for use in broilers and layers. This review is based on the information available at the time of the investigation.

The effects of lactic acid bacteria and yeasts as probiotics on the growth performance, relative organ weight, blood parameters, and immune responses of broiler: A meta-analysis

Introduction: The number of publications in Scopus on this topic increased from less than 50 in 1995 to more than 250 in 2015. In other hand, inconsistency in results about the correlation between yeast and lactic acid bacteria as probiotics has been evident since the early publications on use in broilers. Methods: A meta-analysis was conducted to determine relationship between lactic acid bacteria and yeast as probiotics to broiler diets on the growth performance, relative organ weight, blood parameters, and immune response of the broiler. A database was designed based on published data that reported the use of probiotics on the broiler. The method used for selecting articles was based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) method. Articles selected were taken from PubMed, Web of science, Scopus, Google Scholar, and Science direct databases as well as individual. Results: The final database consists of 49 in vivo articles, 93 studies, and 225 treatments. The analysis statement in the system was a PROC MIXED procedure of SAS software. The level of probiotic increased (p &lt;0.001) body weight, body weight gain, and feed intake of broiler. There was a reduction (p &lt;0.01) on feed conversion ratio and mortality on the level probiotic given to broiler. Supplementation of probiotics in broiler diet increased (p &lt;0.001) the weight of liver, spleen, gizzard, bursa of fabricius and carcass yield, while reduced (p&lt;0.001) abdominal fat weight. The probiotic given increased the total of red and white blood cells (both at p &lt; 0.001) but did not affect lymphocyte. Discussion: It can be concluded the yeast act as supporting agent that serves lactic acid bacteria as probiotic increases the growth performance, relative organ weight, blood parameters, and immune response of the broiler.

The effects of lactic acid bacteria and yeasts as probiotics on the growth performance, relative organ weight, blood parameters, and immune responses of broiler: A meta-analysis.

Introduction: The number of publications in Scopus on this topic increased from less than 50 in 1995 to more than 250 in 2015. In other hand, Inconsistency in results about the correlation between yeast and lactic acid bacteria as probiotics has been evident since the early publications on use in broilers. Methods: A meta-analysis was conducted to determine relationship between lactic acid bacteria and yeast as probiotics to broiler diets on the growth performance, relative organ weight, blood parameters, and immune response of the broiler. A database was designed based on published data that reported the use of probiotics on the broiler. The method used for selecting articles was based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) method. Articles selected were taken from PubMed, Web of science, Scopus, Google Scholar, and Science direct databases as well as individual. Results: The final database consists of 49 in vivo articles, 93 studies, and 225 treatments. The analysis statement in the system was a PROC MIXED procedure of SAS software. The level of probiotic increased (p <0.001) body weight, body weight gain, and feed intake of broiler. There was a reduction (p <0.01) on feed conversion ratio and mortality on the level probiotic given to broiler. Supplementation of probiotics in broiler diet increased (p <0.001) the weight of liver, spleen, gizzard, bursa of fabricius and carcass yield, while reduced (p<0.001) abdominal fat weight. The probiotic given increased the total of red and white blood cells (both at p < 0.001) but did not affect lymphocyte. Discussion: It can be concluded the yeast act as supporting agent that serves lactic acid bacteria as probiotic increases the growth performance, relative organ weight, blood parameters, and immune response of the broiler.

Efficacy of Broilers as a Method of Face Fly (Musca autumnalis De Geer) Larva Control for Organic Dairy Production.

Simple SummaryDairy cows housed on pasture are commonly afflicted by face flies, which develop as larvae in cow manure. Some organic dairy producers graze chickens in succession behind cattle as an effort to disrupt the development of dung fly larvae, but this method has yet to be validated as a successful method of pest management. In a controlled research trial, pastured broiler chickens did not reduce the survival of face fly larvae that developed in cow dung pats. This finding was buoyed by broiler behavioral observations, which revealed the broilers were unwilling to forage in dung pats. In general, broilers were reluctant to leave their shelter as solar radiation increased and climatic conditions were associated with the displacement of time allocated to sitting and sleeping behaviors. Dairy producers should take heed when adopting methods of fly control that rely on broiler chickens to willingly forage in cow dung pats especially when climatic conditions are aversive.The objective of this study was to evaluate Freedom-Ranger broiler chickens as a method to control face fly (Musca autumnalis De Geer) larvae in cow dung pats on pasture. Ninety-nine pats in three replicates were inoculated with first-instar larvae and exposed to one of four treatment conditions for 3 to 4 days: (1) an environment-controlled greenhouse (GH); (2) pasture without broilers (NEG); (3) pasture with 25 broilers stocked at a low density of 2.5 m2 of outdoor area per broiler (LOW); and (4) pasture with 25 broilers stocked at a high density of 0.5 m2 of outdoor area per broiler (HIGH). Broiler behaviors and weather conditions were recorded twice daily. Survival rates of larvae (mean, 95% CI) were similar for pats in the NEG (4.4%, 2–9%), LOW (5.6%, 3–11%), and HIGH (3.2%, 2–7%) groups, and was greatest for larvae reared in the GH (54.4%, 36–72%) group compared to all other groups. The proportion of broilers observed pasture ranging was 14.0% (6–28%) but was negatively related to solar radiation. Broilers were never observed foraging in pats. Results indicate that use of broilers may not be an effective method for controlling larvae of dung pat breeding flies.

Local and systemic inflammatory responses to lipopolysaccharide in broilers: new insights using a two-window approach

The inflammatory response involves a complex interplay of local tissue activities designed to recruit leukocytes and proteins from the blood to the infected tissue. For egg-type chickens, we established the growing feather (GF) as an accessible tissue test site to monitor tissue responses to injected test-material. For commercial broilers, whose health depends to a large extent on innate immune system functions, the GF test system offers an important novel window to directly assess their natural defenses. This study was conducted to adapt the GF test system for use in broilers, and use it to simultaneously examine local (GF) and systemic (blood) inflammatory responses initiated by GF pulp injection of lipopolysaccharide (LPS). Specifically, GF of 12 male and 12 female, 5-week-old broilers were injected with LPS (16 GF/chicken; 1 μg LPS/GF). Blood and GF were collected at 0 (before), 6, and 24 h after GF injection. GF pulp was used to determine leukocyte-infiltration and gene-expression profiles, reactive-oxygen-species generation, and superoxide dismutase (SOD) activity. Blood was used to determine blood cell profiles and SOD activity. A time effect (P ≤ 0.05) was observed for most aspects examined. In GF, LPS injection resulted in heterophil and monocyte infiltration reaching maximal levels at 6 and 24 h, respectively. Reactive-oxygen-species generation, SOD activity, and mRNA levels of IL-1β, IL-8, IL-6, IL-10, and cathelicidin B1 were elevated, whereas those of TNF-α, LITAF, SOD1, and SOD2 decreased after LPS injection. In blood, levels of heterophils and monocytes were elevated at 6 h, lymphocytes and RBC decreased at 6 h, and thrombocytes and SOD activity increased at 24 h. Assessment of LPS-induced activities at the site of inflammation (GF) provided novel and more relevant insights into temporal, qualitative, and quantitative aspects of inflammatory responses than blood. Knowledge generated from this dual-window approach may find direct application in identification of individuals with robust, balanced innate defenses and provide a platform for studying the effects of exogenous treatments (e.g., nutrients, probiotics, immunomodulators, etc.) on inflammatory responses taking place in a complex tissue.

Antimicrobial Use in Broilers Reared at Different Stocking Densities: A Retrospective Study.

Simple SummaryBroiler farms are authorized to house animals at different stocking densities (kg live weight/m2) provided that ammonia, carbon dioxide, temperature, and humidity levels are kept under specific limits set by European Union legislation. The role of stocking density on poultry health and welfare, and consequently on antimicrobial use, is still under debate. Herewith, we analyze veterinary prescription data for 2017 pertaining to a representative sample of Italian broiler farms that were authorized to house animals at 33 or 39 kg/m2. The prescribed amounts of antimicrobials in each farm were converted into a total of Defined Daily Doses per year, a non-dimensional unit proposed by the European Medicines Agency (EMA). No differences in terms of antimicrobial use, mortality, and feed conversion rates were noted between the two considered groups, suggesting a minor role of stocking density on animal health and welfare.According to the Directive 2007/43/EC, broiler farms can house animals up to 39 kg/m2, provided that specific environmental requirements are met. However, limited information is available about the effects of stocking density (SD) on broiler health and welfare, including the need for antimicrobial use. In this study, annual data on mortality, feed conversion rate, and antimicrobial use (AMU) are compared between broiler farms with stocking densities of 39 kg/m2 (N = 257) and 33 kg/m2 (N = 87). These farms were distributed throughout Italy and belonged to the same integrated poultry company. Antimicrobial use data were obtained from each farm and production cycle; AMU was expressed using the defined daily doses (DDD) method proposed by EMA. The annual AMU per farm was calculated as the median AMU over all cycles. Stratified analysis by sex and geographical area (Italy vs Northern Italy) showed no significant effect of stocking density on broiler mortality, feed conversion rate, and AMU. However, a higher AMU variability among farms with 39 kg/m2 stocking density vs. those with 33 kg/m2 was found. This study indicates that AMU does not apparently vary between animals reared at different stocking densities in intensive farms.

The efficacy of litter management strategies to prevent morbidity and mortality in broiler chickens: a systematic review and network meta-analysis

A systematic review and network meta-analysis (NMA) were conducted to address the question, 'What is the efficacy of litter management strategies to reduce morbidity, mortality, condemnation at slaughter, or total antibiotic use in broilers?' Eligible studies were clinical trials published in English evaluating the efficacy of litter management in broilers on morbidity, condemnations at slaughter, mortality, or total antibiotic use. Multiple databases and two conference proceedings were searched for relevant literature. After relevance screening and data extraction, there were 50 trials evaluating litter type, 22 trials evaluating litter additives, 10 trials comparing fresh to re-used litter, and six trials evaluating floor type. NMAs were conducted for mortality (61 trials) and for the presence or absence of footpad lesions (15 trials). There were no differences in mortality among the litter types, floor types, or additives. For footpad lesions, peat moss appeared beneficial compared to straw, based on a small number of comparisons. In a pairwise meta-analysis, there was no association between fresh versus used litter on the risk of mortality, although there was considerable heterogeneity among studies (I2 = 66%). There was poor reporting of key design features in many studies, and analyses rarely accounted for non-independence of observations within flocks.

PREVALENCE OF mcr-1 COLISTIN RESISTANT GENE IN Escherichia coli ALONG THE BROILER MEAT SUPPLY CHAIN IN INDONESIA

Colistin is the last drug choice for dealing with the carbapenem-resistant Enterobacteriaceae bacteria; hence, this drug is very crucial to human health. The discovery of a plasmid-mediated colistin-resistant gene, the mobilized colistin resistance-1 (mcr-1), signals a significant global health threat. Colistin sulfate is an antimicrobial agent which has been approved for use in broilers in Indonesia. Thus, this study aimed to measure the prevalence of colistin-resistant E. coli and to detect the mcr-1 colistin-resistant gene in E. coli, and E. coli O157:H7 in the entire supply chain of broilers in Bogor Regency, West Java Province, Indonesia. Samples were taken from 47 flocks that used colistin sulfate (47 samples of cloacal swabs, 47 samples of drinking water, and 47 samples of litters), seventy fresh meat samples and seven samples plucker swabs from seven small-scale poultry slaughterhouses, seventy fresh meat samples from seven traditional markets, and seventy cooked meat samples from seven small restaurants. The isolation of E. coli was done on each of the 358 samples, and 493 isolates were obtained. All the E. coli isolates were then tested for their susceptibility to colistin sulfate by using the agar dilution method. The detection of the mcr-1 gene from the colistin-resistant isolates (minimum inhibitory concentration &gt; 2 µg/mL) was conducted using the polymerase chain reaction (PCR). The prevalence value of colistin-resistant E. coli in all the isolates was at 11.76% (CI 95%; CL 9.21–14.91%), and the prevalence of mcr-1 gene was at 10.55% CI 95%; CL 8.13–13.57%).  A very good agreement correlation existed between the colistin-resistant phenotype and the mcr-1 gene (ĸ = 0.939). The mcr-1 gene was found in 89.66% colistin-resistant E. coli isolates. The two colistin-resistant and mcr-1 carrying gene isolates were identified as E. coli O157:H7 serotype. This research was the first study attempt on the mcr-1 gene in Indonesia, covering the entire supply chain of broiler meat from farms to consumers. The results indicated the necessity to reduce the use of colistin sulfate in broiler management and to improve biosecurity measures, not only in farms but also in the entire supply chain of broiler meat production.

Broiler production without antibiotics: United States field perspectives

Recent United States Food and Drug Administration restrictions on antibiotic use in broilers should have minimal impacts on broiler health and performance. Of more significance are marketing programs that more severely restrict and often totally prohibit the use of antibiotics, including ionophores, in broiler production. The major impacts of antibiotic-free programs include increased neonatal infections due to removal of added antibiotics from Marek’s vaccines, compromised control of coccidiosis and necrotic enteritis, control of litter moisture and the issues associated with wet litter, and general disease control. Management of these issues requires significant adjustments to management and diet and the use of non-antibiotic medications such as chemically-synthesized coccidiostats. While these adjustments can ameliorate the impacts of antibiotic-free programs, performance, health, and welfare problems are likely to exceed those found in programs with unrestricted access to judicious use of all approved medications.

Impacts of calcium and phosphorus concentration, their ratio, and phytase supplementation level on growth performance, foot pad lesions, and hock burn of broiler chickens

Concerns about the environment, nutrition, and farm profits all point to the increasing importance of the phosphorus (P) content of a diet. Animals must now be fed near their P requirements. However, it is very difficult to know the exact P requirements of broilers. The objective of this study was to provide efficacy data of a 6-phytase for use in broilers at different Ca levels and Ca/P ratios. Broilers were randomly assigned to 6 treatments, each with 6 replicates. The treatments comprised diets differing in Ca and P level: 1) normal Ca and total normal phosphorus (Pt) level, 2) normal Ca and low Pt level, 3) low Ca and Pt level, and differing in phytase level (no, normal or high phytase supplementation). During the entire study, lowest BW was obtained when broilers were given the imbalanced (normal Ca and low Pt level) diet with low phytase supplementation. Among the balanced dietary treatments no significant effects on performance were observed. A higher Ca/Pt ratio decreased feed intake, whereas addition of phytase increased feed intake. For the starter period, the most favorable feed conversion was obtained when broilers were fed the imbalanced diet with a high dosage of phytase or the low Ca, low Pt diet supplemented with phytase. For the grower and finisher period, broilers with the highest weight gain had the highest feed intake resulting in comparable feed conversions between treatments. Litter quality was not affected by dietary treatments but prevalence of foot pad lesions and hock burn was significantly influenced by treatments. The highest percentage of both was seen when broilers were given the imbalanced diets. The overall results of this study emphasises the relevance of the Ca/P ratio in modern broiler feeding and P studies. It can be concluded from this study that dietary Ca and P concentrations can be reduced by 20% if done in a balanced way. If done in combination with phytase supplementation, performance results improve even more.

Bioavailability of zinc sources and their interaction with phytates in broilers and piglets

Zinc (Zn) is essential for swine and poultry and native Zn concentrations in feedstuffs are too low to meet their Zn requirement. Dietary Zn bioavailability is affected by phytate, phytase and Zn supplemented in organic form is considered as more bioavailable than inorganic sources. A meta-analysis using GLM procedures was processed using broiler and piglet databases to investigate, within the physiological response of Zn, (1) the bioavailability of inorganic and organic Zn sources (Analysis I); (2) the bioavailability of native and inorganic Zn dependent from dietary phytates, vegetal and supplemental phytase activity (Analysis II). Analysis I: the bioavailability of organic Zn relative to inorganic Zn sources ranged, depending on the variable, from 85 to 117 never different from 100 (P > 0.05). The coefficients of determination of the regressions were 0.91 in broilers and above 0.89 in piglets. Analysis II: in broilers, bone Zn was explained by supplemental Zn (linear and quadratic, P < 0.001) and by supplemental phytase (linear, P < 0.001). In piglets, the interaction between dietary Zn and phytates/phytases was investigated by means of a new variable combining dietary phytic phosphorus (PP) and phytase activity. This new variable represents the remaining dietary PP after its hydrolysis in the digestive tract, mainly due to phytase and is called non-hydrolyzed phytic phosphorus (PPNH). Bone Zn was increased with native Zn (P < 0.001), but to a lower extent in high PP or low phytase diets (ZNN × PPNH, P < 0.001). In contrast, the increase in bone zinc in response to supplemental Zn (P < 0.001) was not modulated by PPNH (P > 0.05). The coefficients of determination of the regressions were 0.92 in broilers and above 0.92 in piglets. The results from the two meta-analyses suggest that (1) broilers and piglets use supplemented Zn, independent from Zn source; (2) broiler use native Zn and the use is slightly enhanced with supplemental phytase; (3) however, piglets are limited in the use of native Zn because of the antagonism of non-hydrolyzed dietary phytate. This explains the higher efficacy of phytase in improving Zn availability in this specie.

Feed intake and activity level of two broiler genotypes foraging different types of vegetation in the finishing period

A study was performed with 2 broiler genotypes (slow and medium growth) restricted in supplementary feed and foraging 2 different mixed vegetations (grass/clover or chicory) to identify possible benefits of herbage on nutrition during the finishing period (80 to 113 d of age). Three hundred birds were included in a 2 × 2 factorial design with groups of 25 birds replicated 3 times. The use of outdoor areas, performance, and forage intake were investigated. To identify possible differences in foraging activity, the use of the range was monitored one day per week at 4 different times of the day. Feed intake from foraging was estimated by killing 4 birds per plot (2 males and 2 females) in the morning and in the evening on 3 d during the experiment and measuring crop content. Vegetation type did not influence broiler use of the free-range area, feed intake, or performance. Differences in the use of the range area, activity level, and feed content in the crops were observed in relation to genotype, sex, age of broilers, and also the time of day. Foraging activity was positively correlated with age. Medium-growth broilers spent more time inside and closer to the broiler houses during the day with increased foraging activity during evenings, in contrast to the slow-growing broilers that showed a more uniform activity during the day. Based on the measurement of crop content it was estimated that the slow-growing genotype had a daily intake of 5 to 8 g of forage per day, whereas the medium-growing genotype had an intake of 9 g for females and 20 g for males. In conclusion, limitation of supplemented protein feed in the finishing period may be acceptable for broilers that have access to highly nutritious vegetation.

Prevalence and antimicrobial susceptibility of Salmonella in Japanese broiler flocks

This study determined the prevalence and antimicrobial susceptibility of Salmonella isolated from broiler flocks in Japan. Caecal dropping samples were collected from 288 broiler flocks between November 2007 and February 2010. Salmonella was prevalent in 248 (86·1%) broiler flocks. The top three serovars were S. Infantis, S. Manhattan and S. Schwarzengrund. S. Infantis was found in all regions tested in this study. However, S. Manhattan and S. Schwarzengrund were frequently found only in the western part of Japan. High antimicrobial resistance rates were observed against oxytetracycline (90·2%), dihydrostreptomycin (86·7%) and ampicillin (36·5%), and 258 (90·5%) of 285 isolates were resistant to two or more antimicrobial agents. Interestingly, 26·3% of isolates were resistant to ceftiofur, especially 38·1% of S. Infantis isolates, although its use in broilers has not been approved in Japan. This study showed that Salmonella is highly prevalent (86·1%) in Japanese broiler flocks, that 90·5% of Salmonella isolates were multidrug-resistant, and that S. Infantis frequently exhibited resistance to cephalosporin antimicrobial agents.

Effects of an Enzymatically Hydrolyzed Yeast and Yeast Culture Combined with Flavomycin and Monensin on Finishing Broiler Chickens

An experiment was carried out to evaluate the relationship of an Enzymatically Hydrolyzed Yeast (EHY) and yeast culture combined with flavomycin and monensin (F + M) under two levels of Digestible Lysine (DLYS) on the growth performance, carcass measurements, nutrient retention and AMEn in broilers. One hundred and thirty two 35 d old Ross B308 male broilers individually housed in holding cages were used. Broilers were assigned to a factorial arrangement of 2 levels of EHY (0 and 1 kg/ton of feed) x 2 levels of F + M (0.0 and 0.05,0.50 kg/ton) x 2 DLYS levels (0.85 and 0.95%). The experiment lasted 2 wks. Results were subjected to analysis of varianza. EHY-fed broilers showed a trend for greater (p<0.10) feed intake, had improved (p<0.05) weight gain, feed conversion ratio and had greater (p<0.01) weight and yield of the carcass, breast and legs. Broilers fed EHY and 0.95% DLYS had higher nitrogen intake and retention and lower AMEn than those with 0.85% DLYS (EHY and DLYS interaction, p<0.05). EHY-fed broilers also had greater dry matter and ashes intake (p<0.01) and retention (p<0.05). The addition of F+M to the diet improved the weight gain (p<0.05), feed conversion ratio (p<0.01), nitrogen retention and AMEn (p<0.05). Broilers fed the 0.95% DLYS diet had greater feed conversion (p<0.05). The addition of EHY and F+M improved the production and nutrient use in broilers but their effects were independent. The EHY and DLYS showed an additive or synergistic relationship on the nitrogen intake and retention and AMEn.

Expression of Angioproliferative Molecules in Plexiform like Lesions in Lungs of Domestic Fowl Selected for Susceptibility to Pulmonary Arterial Hypertension

Domestic fowl (broiler chickens) bred for meat production spontaneously develop pulmonary arterial hypertension (PAH) accompanied by the formation of plexiform‐like complex vascular lesions (CVLs). CVLs formed distal to branch points in inter‐parabronchial pulmonary arterioles that typically exhibit medial hypertrophy and intimal proliferation. The CVLs in the lungs of broilers closely resemble the histology of plexiform lesions in the lungs of human PAH patients. Paraformaldehyde fixed lung tissues from 8‐ to 24‐week old broilers were stained immunohistochemically for detection of various angioproliferative molecules expressed in the CVLs. These molecules include: smooth muscle actin; von Willebrand factor; vascular endothelial growth factor (VEGF); VEGF receptor II; hypoxia inducible factor 1 alpha; survivin; collagen; fibronectin; and tenascin. The CVLs in broiler lungs exhibited positive staining for these molecules. Expression of these molecules within the CVL of PAH‐susceptible broilers combined with the close histological resemblance of CVLs to plexiform lesions of human PAH patients further supports the use of broilers from our PAH susceptible line as an excellent animal model for PAH and plexogenic arteriopathy.“Supported by NIH grant 1R15HL092517”