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PloS One 2022Broiler production in semi-arid tropics must contend with high levels of heat stress, which have implications on stocking density, bird welfare, and profitability. Under...
Stocking density-induced changes in growth performance, blood parameters, meat quality traits, and welfare of broiler chickens reared under semi-arid subtropical conditions.
Broiler production in semi-arid tropics must contend with high levels of heat stress, which have implications on stocking density, bird welfare, and profitability. Under these conditions, optimal stocking densities are likely to be lower than expected, thus must be experimentally determined. Therefore, this study investigated growth performance, haematology, serum biochemistry, carcass and meat quality, sizes of internal organs, and stress biomarkers in response to different stocking densities in broilers reared under semi-arid subtropical conditions. Five hundred, day-old Ross 308 broilers (44.0 ± 5.24 g live-weights) were randomly distributed to 25 replicate pens (1.32 m2 floor space each) to create five stocking densities: 1) 10 birds/pen (SD10); 2) 15 birds/pen (SD15); 3) 20 birds/pen (SD20); 4) 25 birds/pen (SD25); and 5) 30 birds/pen (SD30). There was a linear decrease (P < 0.05) in overall feed intake and weight gain in weeks 2 and 3 as stocking density increased. However, weight gain showed positive and negative quadratic responses (P < 0.05) in weeks 5 and 6, respectively, as stocking density increased. No linear or quadratic effects (P ˃ 0.05) were observed for overall feed conversion ratio, haematological parameters, and meat quality traits in response to stocking density. Symmetric dimethylarginine, alanine transaminase, and albumin levels quadratically increased (P < 0.05) in response to increasing stocking densities. Serum glucose and thigh weight were not affected (P < 0.05) while final body, drumstick, breast, and wing weights linearly declined with stocking density. Increasing stocking density linearly reduced (P < 0.05) the weights of gizzard, proventriculus, caecum, and colon. Stocking density had no effect (P ˃ 0.05) on latency-to-lie. It was concluded that higher stocking densities compromised feed intake, resulting in poor weight gains. Based on weight gain trends observed in week 5, it was determined that Ross 308 broilers should be reared at no more than 20 birds/pen (~15 birds/m2 or 27.27 kg/m2) under the experimental ambient conditions compared to the much higher globally accepted industry standard of 20 birds/m2.
Topics: Alanine Transaminase; Albumins; Animal Husbandry; Animals; Biomarkers; Chickens; Glucose; Meat; Weight Gain
PubMed: 36227929
DOI: 10.1371/journal.pone.0275811 -
Scientific Reports Oct 2022Globally, most gut microbiota-related studies have focused on broilers due to their diverse microbial communities compared to that of layer chicken. However, in Africa...
Globally, most gut microbiota-related studies have focused on broilers due to their diverse microbial communities compared to that of layer chicken. However, in Africa few studies have been undertaken despite the increasing benefits to the poultry industry. The utilization of Insect-Based diets to improve the gastrointestinal function and gut health in poultry is increasingly gaining global attention. Here, we evaluated the potential roles of commercial black soldier fly larvae-based feeds (BSFLF) in reshaping the abundance, composition and diversity of the gut microbiota of layer chickens using high throughput Oxford nanopore Minion sequencing of the full length bacterial 16S rRNA gene. Two hundred and fifty ISA Brown layer chicks were reared in pens for a period of 20 weeks. The layer pullets were allotted 5 dietary treatments that were formulated as follows: control diet (T1): 100% FM + 0% BSFL, T2: 25% BSFL + 75% FM; T3: 50% BSFL + 50% FM; T4: 75% BSFL + 25% FM, and T5: 100% BSFL + 0% FM. Sampling was done from the eight major regions including oesophagus, crop, proventriculus, gizzard, duodenum, ileum, large intestines and ceca. Out of the 400,064 classified reads analyzed, the most dominant phyla identified across the feed treatments were Firmicutes, Bacteroidetes, Proteobacteria and Actinobacteria. The diet treatment with 100% inclusion levels of BSFL showed the highest intra-species alpha diversity and richness according to Chao1 and Shannon index. Intra-species beta diversity assessment revealed that the diet types significantly influenced the abundance of the microbiota, but differences between most abundant taxa were similar. There was increase in abundance of potentially beneficial bacteria (Lactobacillus, Bacteroides and Enterococcus) with increased inclusion levels of BSFLF in layer pullets diets. Across the different gut segments, Lactobacillus dominated all the eight regions and the ceca was the most diverse segment. Our findings unravel complex gut microbial shift in laying hen fed BSFLF and therefore underpins the potential roles of beneficial bacteria as promising prebiotics and probiotics in reshaping of the gut microbiota to maintain good gut health.
Topics: Animal Feed; Animals; Bacteria; Chickens; Diptera; Female; Gastrointestinal Microbiome; Larva; Microbiota; RNA, Ribosomal, 16S
PubMed: 36202892
DOI: 10.1038/s41598-022-20736-0 -
Scientific Reports Sep 2022Aquatic bird bornavirus (ABBV-1), an avian bornavirus, has been reported in wild waterfowl from North America and Europe that presented with neurological signs and...
Aquatic bird bornavirus (ABBV-1), an avian bornavirus, has been reported in wild waterfowl from North America and Europe that presented with neurological signs and inflammation of the central and peripheral nervous systems. The potential of ABBV-1to infect and cause lesions in commercial waterfowl species is unknown. The aim of this study was to determine the ability of ABBV-1 to infect and cause disease in day-old Muscovy ducks (n = 174), selected as a representative domestic waterfowl. Ducklings became infected with ABBV-1 through both intracranial and intramuscular, but not oral, infection routes. Upon intramuscular infection, the virus spread centripetally to the central nervous system (brain and spinal cord), while intracranial infection led to virus spread to the spinal cord, kidneys, proventriculus, and gonads (centrifugal spread). Infected birds developed both encephalitis and myelitis by 4 weeks post infection (wpi), which progressively subsided by 8 and 12 wpi. Despite development of microscopic lesions, clinical signs were not observed. Only five birds had choanal and/or cloacal swabs positive for ABBV-1, suggesting a low potential of Muscovy ducks to shed the virus. This is the first study to document the pathogenesis of ABBV-1 in poultry species, and confirms the ability of ABBV-1 to infect commercial waterfowl.
Topics: Animals; Bird Diseases; Birds; Bornaviridae; Ducks; Influenza in Birds; Poultry
PubMed: 36180525
DOI: 10.1038/s41598-022-20418-x -
International Journal For Parasitology.... Dec 2022Helminths are not usually considered important pathogens for birds of prey. There is a single published report of mortality in raptors due to an air sac trematode...
Helminths are not usually considered important pathogens for birds of prey. There is a single published report of mortality in raptors due to an air sac trematode infection. We report a well-documented death case from massive infection by an air sac trematode of the family Cyclocoelidae in a wild-caught, juvenile male Snail Kite () in Ecuador. The necropsy of a Snail Kite revealed more than 200 trematodes among air sacs, lungs, heart, gizzard, proventriculus, and liver. Within air sacs and lungs, mature flukes were associated with sacculitis, bronchitis, pneumonia, and atelectasis. Using an integrative taxonomic approach with morphological and molecular data, we identified the parasites as (Trematoda: Cyclocoelidae: Ophthalmophaginae). This case provides the first evidence for the pathologic presence of air sac trematodes associated with morbidity in birds of prey in South America. Our results suggest that cyclocoelids may cause debilitation and significant clinical lesions in birds of prey, with potentially fatal consequences.
PubMed: 36157127
DOI: 10.1016/j.ijppaw.2022.09.001 -
Poultry Science Nov 2022Newcastle disease (ND) is a highly contagious viral disease that constantly threatens poultry production. The velogenic (highly virulent) form of ND inflicts the most...
Newcastle disease (ND) is a highly contagious viral disease that constantly threatens poultry production. The velogenic (highly virulent) form of ND inflicts the most damage and can lead to 100% mortality in unvaccinated village chicken flocks. This study sought to characterize responses of local chickens in Ghana after challenging them with lentogenic and velogenic Newcastle disease virus (NDV) strains. At 4 wk of age, chicks were challenged with lentogenic NDV. Traits measured were pre- and post-lentogenic infection growth rates (GR), viral load at 2 and 6 d post-lentogenic infection (DPI), viral clearance rate and antibody levels at 10 DPI. Subsequently, the chickens were naturally exposed to velogenic NDV (vNDV) after anti-NDV antibody titers had waned to levels ≤1:1,700. Body weights and blood samples were again collected for analysis. Finally, chickens were euthanized and lesion scores (LS) across tissues were recorded. Post-velogenic exposure GR; antibody levels at 21 and 34 days post-velogenic exposure (DPE); LS for trachea, proventriculus, intestines, and cecal tonsils; and average LS across tissues were measured. Variance components and heritabilities were estimated for all traits using univariate animal models. Mean pre- and post-lentogenic NDV infection GRs were 6.26 g/day and 7.93 g/day, respectively, but mean post-velogenic NDV exposure GR was -1.96 g/day. Mean lesion scores ranged from 0.52 (trachea) to 1.33 (intestine), with males having significantly higher (P < 0.05) lesion scores compared to females. Heritability estimates for the lentogenic NDV trial traits ranged from moderate (0.23) to high (0.55) whereas those for the vNDV natural exposure trial were very low (≤ 0.08). Therefore, in contrast to the vNDV exposure trial, differences in the traits measured in the lentogenic challenge were more affected by genetics and thus selection for these traits may be more feasible compared to those following vNDV exposure. Our results can form the basis for identifying local chickens with improved resilience in the face of NDV infection for selective breeding to improve productivity.
Topics: Female; Animals; Newcastle disease virus; Chickens; Ghana; Poultry Diseases; Newcastle Disease
PubMed: 36126448
DOI: 10.1016/j.psj.2022.102138 -
Animal : An International Journal of... Aug 2022Heat stress (HS) dramatically impairs the growth performance of broiler chickens, mainly as a consequence of reduced feed intake due to the loss of appetite. This study...
Heat stress (HS) dramatically impairs the growth performance of broiler chickens, mainly as a consequence of reduced feed intake due to the loss of appetite. This study was aimed at evaluating the alterations induced by chronic HS conditions on the morphological and morphometric features of the gastrointestinal (GI) tract and on the expression of some enteroendocrine cells (EECs) involved in the regulation of feed intake in chickens. Three hundred male chickens (Ross 308) were divided into two experimental groups and raised either in thermoneutral environment for the whole fattening period (0-41 days) (TNT group) or subjected to chronic HS conditions (30 °C for 24 h/day) from 35 to 41 days (HS group). Samples of proventriculus, duodenum, jejunum and cecum were collected from 24 broilers (12/group). Haematoxylin-eosin was used for the morphometric evaluations, while immunohistochemistry was applied for the evaluation of EECs expressing ghrelin (GHR), cholecystokinin (CCK), neuropeptide Y (NPY), glucagon-like peptide-1 (GLP-1), and serotonin (5-HT). In the proventriculus, HS reduced total wall thickness and mucous layer height (P ≤ 0.01) as well as mean diameter, circumference, and area of the compound tubular glands (P ≤ 0.001) with respect to TNT. The small intestine of HS birds was characterised by decreased villous height and total thickness (duodenum, P ≤ 0.01; jejunum, P ≤ 0.001), whereas crypt depth and width were reduced only in the jejunum (P ≤ 0.01). HS had negligible effects on the morphological aspects of the cecum. In the proventriculus, an increase in GHR and NPY EECs was observed in response to HS (P ≤ 0.001). Similarly, the small intestine villi of the HS group showed greater GLP-1 (P ≤ 0.05), 5-HT (P ≤ 0.001) and CCK (P ≤ 0.01) EECs. Moreover, the expression of 5-HT EECs was higher in the duodenal (P ≤ 0.01) and jejunal (P ≤ 0.01) crypts of HS birds, whereas GLP-1 and CCK EECs increased only in jejunal crypts (P ≤ 0.05). Finally, 5-HT EEC expression was increased in the cecum of HS group (P ≤ 0.01). In conclusion, these outcomes demonstrate that chronic HS induces morphometric alterations not only in the small intestine but also in a key organ such as the proventriculus. Furthermore, HS conditions affect the presence and distribution of EECs, suggesting that some GI peptides and biogenic amine may be implicated in the regulation of appetite and voluntary feed intake in heat-stressed broiler chickens.
Topics: Animal Feed; Animals; Chickens; Cholecystokinin; Eating; Glucagon-Like Peptide 1; Heat Stress Disorders; Heat-Shock Response; Hot Temperature; Male; Serotonin
PubMed: 35907384
DOI: 10.1016/j.animal.2022.100600 -
Poultry Science Sep 2022Increasing growth rate, body weight, and breast muscle yield have been linked to broiler muscle problems such as woody breast (WB). The aim of this study was to...
Increasing growth rate, body weight, and breast muscle yield have been linked to broiler muscle problems such as woody breast (WB). The aim of this study was to investigate the internal organ and skeletal muscle development of broilers with WB myopathy under dietary and Eimeria challenge treatments. A 3 diet (control, antibiotic, or probiotic) × 2 challenge (control or Eimeria) × 2 sex factorial arrangement of treatments was used in a randomized complete block design. Ross × Ross 708 chicks were randomly assigned to 96 floor pens with 12 treatment combinations (8 replicates per treatment). Internal organs were sampled on d 13 and 41. Skeletal muscles were sampled on d 41. Internal organ and skeletal muscle weights were analyzed using a 3-way analysis of variance (ANOVA). Relationships between WB and internal organ and skeletal muscle weights were analyzed using one-way ANOVA as all treatments were pooled together and regrouped according to WB scores. On d 41, absolute and relative heart weights were greater in males when they were averaged over diet and challenge treatments (P < 0.001 and P = 0.026, respectively). The birds with WB score 3 had greater absolute heart (P = 0.0002) and spleen weights (P = 0.016), but there was no difference in relative spleen weight (P > 0.05). When averaged over diet and challenge treatments, males have greater absolute duodenum, jejunum, and ileum weights (for all P < 0.0001). Compared with birds with normal breasts, the birds with WB scores 1, 2, and 3 had a greater live weight (for all P < 0.0001) and absolute and relative breast weights (for all P < 0.0001). The birds with WB score 1, 2, and 3 had greater (P < 0.0001) absolute but lower (P < 0.0001) relative drumstick, thigh, and wing weights. Results indicated that broilers with WB had lower relative proventriculus and gizzard weights and greater relative breast meat weight with lower relative drumstick, thigh, and wing muscle weights.
Topics: Animal Feed; Animals; Chickens; Diet; Eimeria; Female; Male; Meat; Muscle Development; Muscle, Skeletal; Muscular Diseases; Poultry Diseases
PubMed: 35896053
DOI: 10.1016/j.psj.2022.102012 -
Frontiers in Microbiology 202216S rRNA amplicon sequencing was used to investigate changes in the broiler gastrointestinal tract (GIT) microbiota throughout the rearing period and in combination with...
16S rRNA amplicon sequencing was used to investigate changes in the broiler gastrointestinal tract (GIT) microbiota throughout the rearing period and in combination with antibiotic treatment. Thirty birds (from a commercial flock) were removed at multiple points throughout the rearing period on days 13, 27, and 33, euthanised, and their GIT aseptically removed and divided into upper (the crop, proventriculus, and the gizzard), middle (the duodenum, jejunum, and ileum) and lower (the large intestine, the caeca, and the cloaca) sections. In a separate commercial flock, on the same farm with similar husbandry practices and feed, doxycycline (100 mg/ml per kg body weight) was administered in drinking water between day 8 and 12 (inclusive) of the production cycle. Birds were removed on days, 13, 27, and 33 and GIT samples prepared as above. The contents of three merged samples from each GIT section were pooled ( = 60), the DNA extracted and analysed by 16S rRNA amplicon metagenomic sequencing and analysed. Major changes in the broiler microbiota were observed as the birds aged particularly with the Firmicutes/Bacteroidetes ratio (F:B) of the lower GIT. Moreover, Chao1, ACE, and Shannon indices showed the antibiotic treatment significantly altered the microbiota, and this change persisted throughout the rearing period. Further research is required to investigate the effect of these changes on bird performance, susceptibility to infections and carriage.
PubMed: 35875529
DOI: 10.3389/fmicb.2022.885862 -
Animals : An Open Access Journal From... Jun 2022In this study, we included 15% doses of infrared-irradiated camelina, flax, and sunflower seeds in the diets of broiler chickens (grower and finisher) and focused on...
Supplementation of Broiler Chicken Feed Mixtures with Micronised Oilseeds and the Effects on Nutrient Contents and Mineral Profiles of Meat and Some Organs, Carcass Composition Parameters, and Health Status.
In this study, we included 15% doses of infrared-irradiated camelina, flax, and sunflower seeds in the diets of broiler chickens (grower and finisher) and focused on assessing the effects on the production traits, selected slaughter analysis parameters, nutrients, and minerals in breast and drumstick meat and some organs, i.e., liver, proventriculus, and heart. In total, 200 one-day-old broiler chickens were assigned randomly to four treatments with five replicate cages of 10 broiler chickens per cage (five females and five males). The experiment lasted 6 weeks. In the group of broiler chickens in which diets were supplemented with micronised camelina and flax seeds, there was an increase in (p < 0.05) breast, thigh, and drumstick weight and a decrease (p < 0.05) in the abdominal fat of the carcasses. The oilseed treatments reduced the ether extract content and the calorific value in the breast and drumstick muscles and organs. The flax seeds contributed to an increase in the contents of Ca (breast muscle and liver), Cu (breast muscle and proventriculus), and Fe (drumstick muscle and heart). Likewise, some blood parameters were influenced by supplementation with infrared-irradiated camelina and flax seeds, for example, there was a decrease in the haemoglobin level and the mean corpuscular haemoglobin concentration (p < 0.05). The oilseed treatments also modified the contents of Fe and Ca in the blood plasma of broiler chickens (p < 0.05). It may be concluded that infrared-irradiated camelina, flax, and sunflower seeds can be regarded as good diet components exerting positive effects on the dietary value of poultry meat and organs used in dietetics.
PubMed: 35804522
DOI: 10.3390/ani12131623 -
BMC Veterinary Research Jun 2022Transmissible viral proventriculitis (TVP) causes significant economic loss to the poultry industry. However, the exact causative agents are obscure. Here we examine the...
BACKGROUND
Transmissible viral proventriculitis (TVP) causes significant economic loss to the poultry industry. However, the exact causative agents are obscure. Here we examine the virome of proventriculus from specified pathogen free (SPF) chickens that reproduced by infection of proventricular homogenate from broiler chicken with TVP using long read sequencing of the Pacific Biosciences RSII platform. The normal SPF chickens were used as control.
RESULTS
Our investigation reveals a virome of proventriculitis, including three Gyrovirus genera of the Aneloviridae: Gyrovirus homsa1 (GyH1) (also known as Gyrovirus 3, GyV3) (n = 2662), chicken anemia virus (CAV) (n = 482) and Gyrovirus galga1 (GyG1) (also known as avian Gyrovirus 2, AGV2) (n = 11); a plethora of novel CRESS viral genomes (n = 26) and a novel genomovirus. The 27 novel viruses were divided into three clusters. Phylogenetic analysis showed that the GyH1 strain was more closely related to the strains from chicken (MG366592) than mammalian (human and cat), the GyG1 strain was closely related to the strains from cat in China (MK089245) and from chicken in Brazil (HM590588), and the CAV strain was more closely related to the strains from Germany (AJ297684) and United Kingdom (U66304) than that previously found in China.
CONCLUSION
In this study, we revealed that Gyrovirus virome showed high abundance in chickens with TVP, suggesting their potential role in TVP, especially GyH1. This study is expected to contribute to the knowledge of the etiology of TVP.
Topics: Animals; Chicken anemia virus; Chickens; Gyrovirus; Mammals; Phylogeny; Poultry Diseases; Proventriculus; Stomach Diseases; Virome
PubMed: 35768837
DOI: 10.1186/s12917-022-03339-9