ABSTRACT An experiment was conducted to evaluate the effects of supplementing Linum usitatissimum (flaxseed) with Moringa oleifera leaf (moringa) on the carcass quality, fatty acids profile, and oxidative stability of broiler chicken. A total of 240 one-day-old mixed-sex Cobb 500 broilers were assigned to the following four dietary treatments: T1 - Control diet; T2 - Flaxseed 0.5% + Moringa 1%; T3-Flaxseed 1%+ Moringa 1%; and T4-Flaxseed 1.5% + Moringa 1%. The final body weight gain was similar in all groups after 35 days, with significantly (p<0.05) reduced feed intake in T4 compared to the control. The thiobarbituric acid reactive substances (TBARS) values of the meat were reduced in the flaxseed and moringa groups (p<0.05) compared to the control. Cholesterol content in thigh meat decreased significantly (p<0.05) in groups T3 and T4 compared to the control. In breast and thigh meat, the omega 3 fatty acids were higher, alongside significantly increased polyunsaturated fatty acids, and a lower omega 6 to omega 3 ratio (except in the T2 group) was observed in the thigh meat of the flaxseed and moringa groups (p<0.05). Overall, the results indicate that diets with up to 1.5% flaxseed and 1% moringa improved meat composition and omega 3 fatty acids and reduced the lipid oxidation of broiler meat.
ABSTRACT The study aimed to evaluate dietary Lactiplantibacillus pentosus [LP]-based probiotic as an alternative to in-feed antibiotics for broilers fed diets containing different nutrient densities. A total of 630 day-old male Ross 308 broiler chicks were randomly assigned to 42 pens (15 birds/ pen) in a 2×3 factorial design with three additives (none, salinomycin at 60 mg/kg, or LP at 1.0 × 108 cfu/kg) and two nutrient density levels (optimal [OPT] or reduced [DEF]). The OPT diets increased (p<0.05) body weight gain in relation to the DEF ones. The LP diet impaired body weight gain and feed intake compared with the control and salinomycin diets (p<0.05). The LP diet lowered feed conversion ratio in the OPT diet, but increased it in the DEF diet, leading to a significant interaction between the two factors (p<0.05). Breast meat yields were increased in the salinomycin group but decreased in the LP group as compared to the control group (p<0.05). CIE a* and b* values in breast meat and CIE a* value in thigh meat were highest in broilers fed salinomycin as compared to the control groups (p<0.05). The OPT diets increased cooking loss in breast meat and decreased CIE L* value in thigh meat (p<0.05) in comparison to DEF diets. Serum superoxide dismutase was higher in the salinomycin and LP groups than in the control group (p<0.05). The salinomycin diet lowered jejunal secretory immunoglobulin A compared with the control group (p<0.05). An interaction between additives and nutrient density on serum glutamic oxaloacetic transaminase was observed (p<0.05). Under the conditions of this study, dietary L. pentosus S14 increased serum SOD activity but impaired growth performance and breast meat yield; therefore, this strain cannot be recommended as a direct replacement for salinomycin without further dose optimization, strain validation, and challenge-model testing.
ABSTRACT This study evaluated the productive performance and economic feasibility of including biological silage from Colossoma macropomum by-products (BST) in the diets of commercial laying hens at different stages of the production cycle. Two experiments were conducted using young hens (23 weeks old) and older hens (83 weeks old), fed diets containing 0, 1, 2, 3, and 4% BST for 63 days. Productive performance (feed intake, egg production and mass, feed conversion) and economic parameters (feed cost, revenue, profit, break-even point, and profitability index) were analyzed. In young hens, inclusion levels up to 1% BST resulted in performance and profitability similar to the control group, while higher levels significantly impaired egg production and economic indicators. In older hens, inclusion levels of 1% to 2% provided better productive performance and greater financial returns, particularly due to reduced unit egg cost and increased profitability. From 3% onward, negative effects similar to those observed in the first group were noted. It is concluded that BST is a viable alternative ingredient in layer diets, provided its inclusion is adjusted according to the birds’ production phase. The rational use of BST promotes the valorization of regional residues, contributing to the economic and environmental sustainability of poultry farming in the Amazon region.
ABSTRACT Escherichia coli plays a key role in disseminating antimicrobial resistance genes within and between bacterial populations. Previous studies have examined isolated stages of the poultry production chain. This study characterized the antimicrobial resistance profiles of E. coli strains collected across all stages of a chicken meat production system to clarify how resistance spreads. Samples were collected from breeders, hatcheries, broiler farms, and slaughterhouses of a single poultry company in southern Brazil. Isolates were evaluated for antimicrobial susceptibility, multidrug resistance (MDR), multiple antibiotic resistance (MAR) index, and extended-spectrum β-lactamases (ESBL) production. The overall resistance rate was 24.18%. The sampling source was associated with resistance to gentamicin, neomycin, ceftazidime, cefazolin, and sulfonamides. More than 60% of isolates were resistant to β-lactams, although no ESBL producers were detected. MDR occurred in 54.95% of isolates, with no significant association with the sampling source. MAR values were highest in slaughterhouses (0.35), followed by broilers (0.28), hatcheries (0.27), and breeders (0.23), with no association between MAR and sample source. These associations likely reflect continuous or recurrent antimicrobial use during specific production stages. Despite established links between antimicrobial use and resistance in poultry systems, substantial knowledge gaps remain and require further investigations to fully understand resistance dynamics.
ABSTRACT Under commercial conditions during a respiratory challenge, birds fed 25 mg Hydroxytyrosol (HT)/kg of feed had higher body weight (BW) (p=0.02) and BW gain (BWG) (p=0.02) compared with birds fed 50 mg HT/kg of feed from 1 to 20 days. Over the entire period (40 days), HT affected BW, BWG, and feed conversion ratio (FCR) (p≤0.01), whereas feed intake (FI) and viability were not affected. Broilers fed 25 mg HT/kg of feed showed the highest BW and BWG (p=0.01), while the birds fed 10 mg HT/kg of feed showed the best feed conversion ratio (FCR) (p=0.004). RT-PCR analysis of throat swabs of dead animals and litter revealed the presence of infectious bronchitis virus (IBV) and low pathogenic avian influenza (LPAI) H9N2 in chickens treated and untreated with HT. In vitro assays indicated that HT reduced H9N2 infectivity after 24 h at concentrations as low as 0.01 mg/mL. In the in ovo model, HT concentrations ≥1 mg/mL were well tolerated and were associated with fewer typical IBV macroscopic lesions (dwarfism or hemorrhage) compared with the positive control.
ABSTRACT The development of the gastrointestinal tract and gut morphology is greatly influenced by the composition of the gut microbiota, as well as the structure and function of the digestive system. A properly balanced gut microbiota facilitates the digestion of feed components, promotes nutrient utilization, and stimulates the development of the immune system. Previous studies have demonstrated that the gut microbiota can be influenced by the administration of feed additives such as prebiotics or probiotics. These compounds affect the animal’s humoral immunity, enhancing nutrient absorption, which in turn improves growth performance and overall health. More recently, insects have been identified as a significant source of nutrients and biologically active compounds that can positively influence gastrointestinal health by modulating microbiome diversity without negatively affecting production parameters or product quality. Chickens can be fed insects directly, or the insects can be processed into insect meals and added to the diet as a supplement. Thus, the objective of this review is to provide a comprehensive insight into recent findings published over the last ten years regarding the role of insects in enhancing the health, gut status, and welfare of poultry in production systems.
ABSTRACT This study evaluated the effects of three commonly used imported infectious bronchitis (IB) vaccines on the health and production of broilers. Two hundred and forty day-old Ross-308 broiler chicks were randomly allotted to four groups (six replicates of ten birds each). The control group received no vaccine administration, while groups IB4-91, IBMa5C, and IBH-120 were vaccinated against IB vaccines on days 7 and 21. The vaccine used in Group IB4-91 was from Nobilis®, Vety-Care Pvt Ltd, in group IBMa5 from Nobilis®, and in group IBH-120 from Medivac, Hilton Pharma. Growth performance parameters (feed intake, body weight gain, feed conversion ratio) were not significantly different (p>0.05) among the groups throughout the 35-day trial. However, immune response and mortality were significantly influenced by vaccine type. Group IB4-91 showed a significantly higher antibody titer (p=0.032) and achieved 0% mortality, which was significantly lower (p=0.030) than the other groups. In contrast, control, IBMa5, and IBH-120 all displayed 3.33% mortality and exhibited mild to moderate respiratory symptoms, with post-mortem findings revealing tracheal and lung congestion. It is concluded that while the tested imported vaccines did not impact growth, the IB4-91 vaccine provided superior protection, as evidenced by the highest antibody titers and the complete absence of mortality.
ABSTRACT The aim of this study was to assess the effect of in-feed antibiotic (enramycin), prebiotic (Actigen®+XOS), and bioactive peptides (BPs, Lassotide+®) derived from Bacillus subtilis fermentation on broiler performance, immune response, gut health, and nutrient utilization. A total of 900 male broiler chicks (Ross-308) were acquired and randomly allocated into six feeding treatments: (1) Control, fed with basal diet; (2) Antibiotic; basal diet + enramycin at 200g/ton in starter and grower phases; (3) Pre; basal diet + prebiotic at 400g/kg in both starter and grower phases; (4) L2SF; basal diet + BPs at 200g/ton in both starter and grower phase; (5) L2S, basal diet with BPs at 200g/ton only in the starter phase (6) L2F; basal diet supplemented with BPs at 200g/ton exclusively in the grower phase. The results indicated that body weight gain was significantly higher (p≤0.05) in the L2SF group as compared to the control during the overall period. Correspondingly, L2SF showed superior (p≤0.05) nutrient utilization, feed conversion ratio, and carcass traits as compared to the control group. The birds in the L2SF group showed notably (p≤0.05) diminished levels of pathogenic bacteria in comparison to the control. Moreover, the antibody titer and the weight of the immune organs were considerably (p≤0.05) greater in L2SF as compared to the control group. The findings of the present study demonstrate that the inclusion of BPs (Lassotide+®) at 200g/t in both starter and grower phases can successfully replace antibiotics and possess equivalent or better potential compared to prebiotics.
ABSTRACT The study aimed to determine the chemical composition and energetic value of passion fruit seed (PFS) and evaluate the inclusion of PFS in quail diets regarding performance, carcass characteristics, litter quality, meat lipid stability, and economic viability. In the metabolism assay, 108 21-day-old quails were distributed in a completely randomized design, with one reference diet and two test diets substituting 20% and 40% of the reference diet with PFS, and 6 replications of 6 quails. The AMEn values determined were 4,214.00 kcal/kg DM and 4,127.33 kcal/kg DM for 20% and 40% PFS, respectively. In the performance assay, 432 quails aged 7 to 42 days were distributed in a completely randomized design with inclusion levels of 0, 5, 10, 15, 20, and 25% of PFS, with 6 replications of 12 quails. The results show that feed conversion increased starting at a PFS inclusion of 15%. A linear increase was observed in the percentage of gizzards from quails fed with 25% PFS, along with a linear effect on economic variables starting from a 20% inclusion. It was concluded that PFS can be used at a level of up to 15% in the diets of meat quails aged 7 to 42 days.
ABSTRACT This study aimed to analyze the economic viability of replacing sawdust and rice husk bedding with plastic flooring in broiler chicken production, using simulation methods. The viability indicators used were the net present value (NPV), internal rate of return (IRR), modified internal rate of return (MIRR), profitability index (PI), discounted payback period (DPP), and equivalent uniform annual value (EUAV). Scenario analysis, sensitivity analysis, and Monte Carlo simulation were conducted in this study. The results revealed that the initial investment required to implement plastic flooring was R$ 350,000.00. The average price paid for the manure produced was R$ 250.00 per ton, which was converted into revenue in the project’s cash flow. The cash flow result was positive, with an NPV of R$ 64,786.23 over the entire study period. The IRR was 18.5% per annum, and the MIRR was 16.7% per annum, confirming the project’s economic viability given the market conditions at the time of the study. The profitability index (PI) was 1.35, indicating high profitability, whereas the discounted payback period (DPP) was 4.5 years, indicating an adequate time to recover the investment. The Monte Carlo simulation highlighted a low risk of negative NPV, emphasizing the project’s economic robustness. In addition to the economic benefits, the adoption of plastic flooring improved hygiene and welfare, reduced waste production, and enhanced the sustainability of poultry production. These factors make replacing flooring with plastic a promising choice for poultry producers with the Sustainable Development Goals. Therefore, replacing conventional bedding with plastic flooring in broiler production is economically viable, improving profitability and promoting sustainability in poultry production.
ABSTRACT This study investigated the significance of layer chicken genotype on hatchling weight, growth performance and egg quality traits using a total of 312 Hy-Line and Akbay layer chickens. The body weight (BW) during most of the rearing period and the initial egg-laying cycle was significantly higher for the Hy-Line genotype as compared to the Akbay (p<0.05). Egg weight (EW) (at 28, 32, and 44 wk), egg length (EL) (at 32 wk), egg diameter (ED) (at 28, 32, 36, and 44 wk), eggshell thickness (EST) (at 24, 28, 36, 44, and 48 wk), and shell weight (SW) (at 24, 28, 32, 44, and 48 wk) were significantly higher among Hy-Line than Akbay (p<0.05). The egg breaking strength (EBS) at 24 weeks was higher for the Akbay genotype; however, the EBS at 44 and 48 weeks of age was higher among Hy-Line birds (p<0.05). The yolk height (YH) (28 and 32 wk) and yolk index (YI) (28 wk) were significantly higher for Hy-Line than Akbay hens (p<0.05). At 44 weeks, the a* value was higher for the Akbay genotype; however, the a* value was higher for Hy-Line hens at 52 weeks (p<0.05). Additionally, the b* value at 28 weeks was higher among Akbay hens than Hy-Line hens (p<0.05). The albumen length (AL) (at 28 and 44 wk), albumen diameter (AD) (at 28, 40, and 44 wk), and albumen pH (A-pH) (at 28 wk) were significantly higher among Akbay hens; however, the albumen height (AH) (at 24 and 28 wk), albumen index (AI) (at 28 wk), and Haugh unit (HU) (at 28 wk) were significantly higher for Hy-Line hens (p<0.05). It was concluded that, compared to the Akbay strain, Hy-Line was characterized by superior growth performance and other external and internal traits with economic importance, including egg weight, breaking strength, Haugh unit, and shell thickness.
ABSTRACT Manure generated from livestock farming is one of the most abundant forms of biomass. In Türkiye, livestock is categorized into sixteen distinct animal types, and the distribution of these types across districts is published online via the Biomass Energy Potential Atlas (BEPA). This study first calculates the biomass potential associated with Türkiye’s animal types. Subsequently, the animal species with the highest biomass potential are identified. To conduct a more detailed analysis, the contribution of each province to the national biomass potential was evaluated. Since a detailed analysis covering the entire country would significantly expand the scope of the study, the focus was narrowed to the Marmara Region. The Marmara Region, one of Türkiye’s seven geographical regions, is located in the northwest, comprises 11 provinces, and is home to the country’s most densely populated and industrialized cities. The compatibility of the methodology employed by BEPA with the existing literature was assessed, and the potential energy value obtainable from the region was calculated. Finally, the study investigated how many biomass-powered absorption cooling facilities, each with a 10 kW cooling capacity, could be supplied by the biogas produced from the manure of the four dominant species-broiler chickens, laying hens, purebred cattle, and crossbred cattle. As a result, it was found that the poultry population in Türkiye numbers approximately 360 million, of which around 355 million consist of broiler and laying hens. The Marmara Region, particularly the provinces of Sakarya and Balıkesir, stands out in poultry farming, hosting 93.5 million chickens. If the biomass from the four identified species in the region were converted into energy, it would be possible to establish approximately 38,510 facilities.
ABSTRACT This study evaluated the effects of taurine supplementation administered in ovo and via drinking water on growth performance, carcass traits, oxidative stress status, and white striping (WS) incidence in broiler chickens. A total of 720 fertilized eggs were randomly allocated to three groups: Control (no treatment), Sham (sterile distilled water injection), and in ovo taurine (IOT; 1.30 mg/egg). After hatching, chicks were assigned to four experimental groups: Control, Sham, IOT, and taurine via drinking water (DWT), administered daily as a freshly prepared stock solution (250mg/10mL). Growth performance was monitored over 42 days. The IOT group exhibited reduced feed intake and body weight gain during the later growth stages. Carcass analysis revealed significantly lower breast and thigh weights in the IOT group (p<0.001), whereas liver weight was highest in the DWT group. No significant differences in WS scores or breast pH were observed among treatments (p>0.05). Histological evaluation showed that IOT significantly reduced the severity of lipidosis, particularly toward the end of the experimental period (p<0.001). Regarding oxidative stress, malondialdehyde (MDA) levels were elevated in the Control and DWT groups, while reduced glutathione (GSH) and superoxide dismutase (SOD) activities were significantly higher in the IOT and Sham groups (p<0.001). The lowest expression of heat shock protein 70 (HSP70) and the highest levels of fibronectin type III domain-containing protein 5 (FNDC5/irisin) were observed in the IOT group (p<0.001). Although in ovo taurine supplementation did not improve growth performance or carcass yield, it enhanced antioxidant capacity and muscle metabolism.
ABSTRACT This study evaluated the effects of probiotics added to rations with different protein levels on growth performance and ileal Escherichia coli (E. coli) populations in local ducks. A total of 240 Alabio ducks were allocated to five treatments, with six replications, in a completely randomized design. Treatments were: T1=control (basal diet/BD); T2=BD+4000 ppm probiotic; T3=BD with reduced protein (starter 16% CP, grower 14% CP)+4000 ppm probiotic; T4=BD with further-reduced protein (starter 14%) CP, grower 12% CP+4000 ppm probiotic; T5=BD+4000 ppm commercial probiotic. Parameters were feed intake, body weight, weight gain, feed conversion ratio, ileal E. coli counts, and mortality. Probiotic supplementation significantly improved performance in the starter and grower. Mortality was 1.25% across treatments. During the starter, the higher LBW was T5 (448 g/duck), and the lower was T4 (339 g/duck). Meanwhile, the lower FC was T1 (835 g/duck), and the worst was T5 (911 g/duck and the higher body weight gain was T5 (408 g/duck). T1 and T5 were similar on FCR (211 vs 2.23 g/g). The grower showed no significant differences (p>0.05) among all treatments for FC, LBW, and BWG, but significant differences for FCR. The best FCR was T4 (2.73 g/g) and the worst was T5 (3.07 g/g). The probiotic also reduced the number of E. coli in the ileum. It was concluded that the combination of giving 4000 ppm probiotics and low protein levels (12%) improved the performance of local ducks and reduced the population of ileal E. coli in local ducks at various levels of feed protein.
ABSTRACT Poultry farming is a key sector of the Brazilian economy, marked by large-scale production. Consumption increased during the SARS-CoV-2 pandemic and due to global pig herd diseases, driven by poultry’s affordability and versatility. However, industry growth has also led to a rise in diseases, including those caused by Escherichia coli. This study evaluated the sensitivity profile of E. coli strains isolated from poultry hatcheries in southern Brazil against selected antimicrobials and two disinfectants (quaternary ammonium and sodium hypochlorite), as well as their biofilm-forming ability. Samples were collected at different stages of fertile egg incubation and identified through conventional bacteriology. E. coli was found in 18% of samples, with 96.74% producing biofilm and all being sensitive to both disinfectants. Antimicrobial resistance was highest for amoxicillin and tetracycline (79.35%), followed by enrofloxacin (69.56%) and kanamycin (26.09%). Multidrug resistance occurred in 53.26% of isolates. These findings underscore the need for standardized tests to monitor biofilm-producing bacteria and their antimicrobial susceptibility in poultry farming.
ABSTRACT This study reviewed the scientific literature on the application of single nucleotide polymorphism (SNP) markers in chickens (Gallus gallus domesticus), aiming to assess research trends, contributing countries, and the most investigated genes in poultry genetics. The bibliometrix package in R was used to dig through data from Web of Science and Scopus, covering the period ranging from 2008-2024. After cleaning out the duplicates, 1,668 articles remained. Since 2008, the numbers kept climbing, peaking in 2024 with 137 papers, which amounts to an average of 87 per year. The US, South Korea, and China were the largest three country origins in terms of output, with China alone producing 723 studies. Countries like Brazil were also important sources, which hints at there still being significant room for global collaboration in this field. The most frequent keywords were “growth” and “egg production,” underscoring a predominant research focus on productive and reproductive traits. The most cited genes were GH, IGF, PRL, MHC, CORT, MCR1, and VIP, which relate to growth, egg production, and disease resistance. Our data expand the body of SNP-based research in poultry science, while also highlighting the potential of those markers for use in breeding programs that aim at increasing productivity and sustainability.
ABSTRACT Parasitic infections in chickens are responsible for significant loss in the economy. This study compared the anthelmintic activity of Trachyspermum ammi (ajwine), apple cider vinegar, and synthetic drugs against gastrointestinal nematodes in chickens and assessed their effects on weight gain.100 naturally infected chickens with Ascaridia galli and Heterakis gallinarum, and 20 healthy fowls were studied. Infected chickens were divided into four groups for treatment with albendazole (20 mg/kg body weight), levamisole (25 mg/kg body weight), ajwine (3 g/kgbw), Apple cider vinegar (ACV) (5 ml/kg body weight), respectively, and the fifth one remained untreated (-ve control). Healthy chickens served as a positive control. Anthelmintic efficacy was assessed using the fecal egg count reduction percentage (FECR%) on days 31, 39, and 53 post-treatment. Albendazole was found to be most effective against nematodes with FECR% of 75.36% on day 31, 98.58% on days 39, and 99.70% on day 53. On day 31, levamisole and ACV were found to be significantly less effective than albendazole, but their effects were increased from day 39 to day 53. ACV showed FECR 89.45% against A. galli and 84.32% against H. gallinarum at day 53. ACV showed similar deworming potential at day 53 to levamisole, indicating its strong anthelmintic efficacy. T. ammi was found to be more effective in weight gain and A. galli deworming. Specimens treated with Albendazole showed 10.04±0.48 g/day weight increase, levamisole 8.64±0.42 g/day, T. ammi 8.63±0.39 g/day, and ACV 8.67±0.44 g/day indicating both herbal products act as anthelmintics and are also involved in improving the digestive abilities of fowls.
ABSTRACT This study evaluated the effects of different plant-based lipid sources on the performance, serum biochemical profile, meat physical traits, body temperature, and intestinal histomorphometry of Japanese quails during the rearing phase. A total of 400 Japanese quails were assigned to a completely randomized design with five dietary treatments consisting of soybean, corn, cottonseed, sunflower, or canola oil included at 25 g/kg, with ten replicates of eight birds each. Quails fed diets containing cottonseed, sunflower, or canola oil exhibited lower feed conversion ratios compared with those fed corn oil (p<0.01), without affecting body or surface temperature, meat quality traits, or serum biochemical parameters (p>0.05). In addition, birds receiving cottonseed oil showed a higher villus-to-crypt ratio in the ileum (p<0.01). Dietary inclusion of cottonseed oil at 25 g/kg improved feed efficiency and intestinal morphology in Japanese quails during the rearing phase, without inducing adverse changes in serum biochemical indicators related to lipid metabolism.
ABSTRACT This study focused on the effects of five different lactic acid bacteria (Lactobacillus salivarius 05, Lactobacillus chiayiensis AACE 3, Lactobacillus paracasei XLK 401, Lactobacillus casei AACE 4, and Lactobacillus pabuli AACE 5) on the immune system, growth performance, and antioxidant capability of Nandan Yao Chickens. Following a 21-day feeding period during which 180 one-day-old Nandan Yao Chickens received one of five Lactobacillus strains (1×106 CFU/g) or a control diet, three chickens per group were euthanized for sample collection. Blood and tissues were analyzed to evaluate immune function, antioxidant status, and gut microbiota composition. The supplementation with Lactobacillus strains enhanced growth and improved gastrointestinal health in Nandan Yao Chickens through both unique and overlapping physiological pathways. Specifically, L. paracasei XLK 401 and L. salivarius 05 were most effective for weight gain. All tested Lactobacillus strains demonstrated immunological safety and exhibited strain-specific improvements in antioxidant capacity (SOD, CAT, GSH-Px). Of particular significance was the observation that four strains reliably enhanced Akkermansia levels, which indicates a targeted, prebiotic-like influence on the composition of the intestinal microbiota. The five Lactobacillus strains significantly improved the growth performance, antioxidant enzyme activity and immune function of Nandan Yao Chickens, providing a theoretical basis for the scientific application of lactic acid bacteria in poultry farming.
ABSTRACT This study explored how salidroside alleviates pulmonary arterial hypertension (PAH) and ascites in broilers exposed to high-altitude hypoxia. Three groups of broilers (n = 80 each) were kept for 42 d under hypoxic (14.0-16.0 % O2), normoxic (20.8-21.5 % O2) or hypoxic + salidroside (50 mg kg-1 diet) conditions. On days 21, 35 and 42, mortality was recorded; serum SOD, GSH-Px and CAT activities, and MDA levels were quantified, and the right ventricular hypertrophy (RV/TV) index was calculated. At day 42, pulmonary arteries were sampled for histopathology, immunohistochemistry (Caspase-3, Ki67, PCNA), Western blot, RT-qPCR, and immunohistochemistry for CaSR. Compared with the hypoxic group, salidroside and normoxic broilers showed higher antioxidant enzyme activities, lower MDA, lower RV/TV index, and reduced total and ascites-related mortality (all p<0.05). Hypoxia-induced thickening of the arterial wall, decrease in Caspase-3, and increases in Ki67 and PCNA were all reversed by salidroside or normoxia. CaSR mRNA and protein levels were also downregulated in both non-hypoxic groups (p<0.05), with no difference between them (p>0.05). Salidroside thus mitigates hypoxic PAH and ascites by preserving right-heart function, suppressing pulmonary arterial remodeling, enhancing antioxidant capacity, and inhibiting CaSR signalling. In conclusion, salidroside mitigated PAH and ascites under high-altitude conditions by maintaining normal right heart function, reducing pulmonary artery pressure, enhancing antioxidant capacity, and modulating CaSR expression.
