Comparison of Characteristics and Differences in Early Immune Organ Development in Different Strains of Tianfu Broiler

To effectively develop and utilize high-quality Tianfu broilers, this study evaluated the morphological and structural characteristics of the immune organs of such broilers with different strains (HS1 and HS2) at different developmental stages and analyzed the distribution of mast cells by toluidine blue staining. Moreover, the localization and expression of immunoglobulin, complement C3, C4 and CD3 in immune organs were also detected. The results showed that although there was no significant difference in the development of immune organs in the HS1 and HS2, the number of lymphatic follicles and capsule thickness in the spleen and bursa of Fabricius in HS1 were greater than those in HS2. Additionally, the number of mast cells in the spleen of HS1 was greater at Day 1 and Day 21 and was significantly higher than that of HS2 (p<0.05); the number of mast cells in the bursa of Fabricius reached 9.17 on Day 7, which was significantly higher than that of HS2 (p<0.05). Moreover, the serum IgA and IgM levels in HS1 were higher than those in HS2 on Day 14 and 21 (p<0.05). In addition, the complement C3 content in HS1 was significantly or extremely significantly higher than that in HS2 on Days 1, 14 and 21 (p<0.01, p<0.05), respectively, but significantly lower than in HS2 on Day 7 (p<0.05). These results indicated that the disease resistance of the HS1 line was stronger than that of the HS2 line, which lays a foundation for future disease- resistance breeding of Tianfu broilers.(AU)

Effect of Bacillus Subtilis on Immune Function of Hd11 Chicken Macrophages

Poultry is frequently contaminated by Salmonella, a pathogen leading to human health concern worldwide. This study aimed to evaluate the effect of Bacillus subtilis (BS)strain 048 (BS048) on the activation, phagocytosis, sterilization, cytokine secretion, and nitrogen oxide synthesis of HD11 chicken macrophages subjected to Salmonella enteritidis challenge, using lipopolysaccharide treatment as a negative control. The results showed: (1) BS048 had no significant effect on extracellular lactate dehydrogenase activity (p>0.05), while lipopolysaccharide treatment significantly increased extracellular lactate dehydrogenase activity (p >0.05), while lipopolysaccharide treatment significantly increased extracellular lactate dehydrogenase activity (p 0.05);(2)BS048 significantly upregulated the expression levels of pro-inflammatory cytokines (interleukin (IL)- 1â and IL-6), anti-inflammatory cytokines(IL-10 and transforming growth factor-â1), and anti-viral cytokine, interferon-â (p<0.01); ; (3) BS048 significantly upregulated the mRNA expression level of the inducible nitric oxide synthase and its activity as well as extracellular nitrogen oxide level (p <0.01). In conclusion, BS048 could improve antiinflammatory and immune functions of HD11 chicken macrophages, without cytotoxic effects on these cells.(AU)

Detection and Antimicrobial Resistance Profile of Enteropathogenic (EPEC) and Shigatoxigenic Escherichia coli (STEC) in Conventional and Organic Broiler Chickens

Enteropatogenic Escherichia coli (EPEC) and shigatoxigenic E. coli (STEC), are generally poultry and poultry product isolate and can cause serious human infections. Many strains may become resistant to various antimicrobials, which can hinder the treatment of bacterial diseases. Organic farming seeks to avoid the selection and frequency of antimicrobial-resistant bacteria. This study aims to verify the resistance of EPEC and STEC from organic and conventional (industrial) broiler isolates to antimicrobials. All isolates were submitted to disk diffusion test with tetracycline, gentamicin, enrofloxacin, ceftriaxone and amoxicillin + clavulanate (TET, GEN, ENO, CTX, AMC) and PCR to detect specific virulence genes for EPEC and STEC. A total of 297 E. coli strains were isolated, 213 from conventional. In organic broiler, 84 strains were isolated. The strains from the conventional broiler isolates were resistant to five antimicrobials tested: TET 48.82% (104/213), ENO 28.17% (60/213), CTX 15.49% (33/213), GEN 14.55% (31/213), and AMC 7.04% (15/213), and 9.86% (21/213) were considered multidrug-resistant. Organic chicken strains were resistant to four of the antimicrobials tested: TET 35.7% (30/84), ENO 9.5% (8/84), CTX 2.4% (2/84), GEN 4.8% (4/84). Of the strains from the organic broiler chicken isolates, only 1.2% (1/84) was considered multidrug-resistant. No EPEC and STEC were found in the organic chicken samples. The multidrug resistance was characterized in 9.52% (2/21) of the EPEC and 4.76% (1/21) of the STEC. The study demonstrated the absence of EPEC and STEC strains in organic broilers and carcasses and a lower frequency of multiresistant strains compared to conventional breeding.(AU)

Resveratrol Attenuates Heat-Stress-Impaired Immune and Inflammatory Responses of Broilers by Modulating Toll-Like Receptor-4 Signaling Pathway

This study investigated the effect of resveratrol on the immune and inflammatory responses and the mRNA levels of splenic toll-like receptor (TLR)-4 signaling pathway-related genes of broilers under heat stress (HS). One hundred and sixty-two birds were allocated to three groups, each with 6 replicates, for 21 continuous days. The three treatments were as follows: the control group (22 ± 1 °C), the HS (33 ± 1 °C for 10 h d-1 and 22 ± 1 °C for the remaining time) group and the HS + resveratrol (400 mg kg-1) group. At the end of the trial, one bird per replicate close to the average body weight (BW) was selected, exsanguinated, and slaughtered. Compared with the control group, the HS treatment decreased (p<0.05) final BW, average daily gain (ADG), average daily feed intake (ADFI), relative weight of bursa of Fabricius and spleen, serum immunoglobulin (Ig) Y, IgA and interleukin (IL)-10 contents, and splenic IL-10 mRNA level, while it increased (p<0.05) feed/gain, mRNA levels of splenic tumor necrosis factor-α (TNF-α), TLR-4, nuclear factor-kappa-B (NF-κB), IL-1ß, and IL-6. Compared to the HS group, the HS+resveratrol group exhibited increased (p<0.05) final BW, ADG, relative weight of bursa of Fabricius and spleen, serum IgY, IgA and IL-10 contents, and splenic IL-10 mRNA level, while it exhibited lower (p<0.05) TNF-α, IL-1ß and IL-6 contents in serum, and splenic TLR4, TNF-α, IL-1ß, and NF-κB mRNA levels. In conclusion, resveratrol prevented a HS-impairment of the immune function of broilers by blocking the abnormal activation of the TLR4 signaling pathway.(AU)

Effects of Saccharomyces Cerevisiae Supplemented Diet on Production Performance, Egg Quality and Humoral Immunity in Black Australorp and Fayoumi Layers

The present study intended to identify the effects of the Saccharomyces cerevisiae yeast on production performance and parameters related to the quality of layers' eggs. Effects of yeast on immune titers after routine vaccinations against Newcastle disease and infectious bronchitis were also studied. Fayoumi chicken (n=288) were divided in four groups (72 in each), and Black Australorp (n=288) in four groups (72 in each). Both had 12 weeks of age and were kept in 08 groups (3 replicates per treatment). Hens were fed a controlled diet along with the addition of 0.5g, 1.0 g, and 1.5 g of S. cerevisiae per kg of feed, till 25 weeks of age. Feed intake and egg production were measured on a daily basis, while body weight gain and egg weight were measured weekly. Egg quality parameters were evaluated by picking 5 eggs from every group weekly. Birds were vaccinated for Newcastle disease (ND) and infectious bronchitis (IB) at the 18th week. Subsequently, 10 days after vaccination, antibody titers were determined by Hemagglutination Inhibition and Enzyme Linked Immunosorbent Assay for both diseases. Results showed no significant effect of S. cerevisiae on layers' weight gain and feed intake. However, egg production was increased in the experimental group. Moreover, yeast supplementation impacted positively on birds' immune system. In conclusion, probiotic supplementation improved birds' egg production and immunity.(AU)

Exploration of Zingiber officinale effects on growth performance, immunity and gut morphology in broilers / Exploração dos efeitos do Zingiber officinale no desempenho de crescimento, imunidade e morfologia intestinal em frangos de corte

The current study aimed to determine the effects of different levels of Zingiber officinale as a herbal feed additive on growth performance, carcass characteristic, serum biochemistry, total bacterial count (TBC), gut morphology, and immunological parameters of broilers. A total of 1500, day-old broiler chicks (Hubbard) were equally accredited to five treatment groups, each with six replicates (50 birds/replicate). Five experimental diets were prepared using basal diet i.e. with antibiotics positive control (PC), 3 g/kg ginger (group A), 6 g/kg ginger (group B), 9 g/kg ginger (group C) and without antibiotics negative control (NC). Group A and C showed significantly (p<0.05) higher feed intake (FI) as compared to other groups. Group C showed significantly (p<0.05) lower Total bacterial count (TBC) followed by group B as compared to NC. Carcass characteristics showed non-significant effects among different treatments. Mean villi length and width were significantly (p <0.05) higher in all ginger supplemented groups as compared to the control groups. Blood serum parameters including cholesterol, triglycerides, and low density lipoproteins (LDL) were significantly (p<0.05) lower in groups B and C in comparison with the control groups. Whereas high-density lipoproteins (HDL) was significantly higher in group B as compared to the others. In conclusion, ginger supplementation @0.6% in the basal diet significantly improved growth performance and gut morphometry of broilers. It also showed a positive impact on cholesterol, triglycerides and gut microbes. Therefore, ginger could be a better substitute for antibiotic growth promoters.

O presente estudo teve como objetivo determinar os efeitos de diferentes níveis de Zingiber officinale como aditivo à base de plantas medicinais sobre o desempenho de crescimento, características da carcaça, bioquímica sérica, contagem bacteriana total (CBT), morfologia intestinal e parâmetros imunológicos de frangos de corte. Um total de 1.500 pintos de corte de um dia de idade (Hubbard) foram igualmente credenciados em cinco grupos de tratamento, cada um com seis repetições (50 aves/repetição). Cinco dietas experimentais foram preparadas usando dieta basal, ou seja, com controle positivo de antibióticos (PC), 3 g/kg de gengibre (grupo A), 6 g/kg de gengibre (grupo B), 9 g/kg de gengibre (grupo C) e sem controle negativo de antibióticos (NC). Os grupos A e C apresentaram consumo de ração (FI) significativamente (p < 0,05) maior do que os outros grupos. O grupo C apresentou contagem bacteriana total (CBT) significativamente menor (p < 0,05) seguido pelo grupo B em comparação com o NC. As características da carcaça apresentaram efeitos não significativos entre os diferentes tratamentos. O comprimento e largura médios das vilosidades foram significativamente (p < 0,05) maiores em todos os grupos suplementados com gengibre em comparação com os grupos de controle. Os parâmetros séricos do sangue, incluindo colesterol, triglicerídeos e lipoproteínas de baixa densidade (LDL), foram significativamente (p < 0,05) menores nos grupos B e C em comparação com os grupos controle. Enquanto as lipoproteínas de alta densidade (HDL) foram significativamente maiores no grupo B em comparação com os outros. Em conclusão, a suplementação de gengibre a 0,6% na dieta basal melhorou significativamente o desempenho de crescimento e a morfometria intestinal de frangos de corte. Ele também mostrou um impacto positivo sobre o colesterol, triglicerídeos e micróbios intestinais. Portanto, o gengibre pode ser um substituto melhor para os promotores de crescimento com antibióticos.

Exploration of Zingiber officinale effects on growth performance, immunity and gut morphology in broilers / Exploração dos efeitos do Zingiber officinale no desempenho de crescimento, imunidade e morfologia intestinal em frangos de corte

The current study aimed to determine the effects of different levels of Zingiber officinale as a herbal feed additive on growth performance, carcass characteristic, serum biochemistry, total bacterial count (TBC), gut morphology, and immunological parameters of broilers. A total of 1500, day-old broiler chicks (Hubbard) were equally accredited to five treatment groups, each with six replicates (50 birds/replicate). Five experimental diets were prepared using basal diet i.e. with antibiotics positive control (PC), 3 g/kg ginger (group A), 6 g/kg ginger (group B), 9 g/kg ginger (group C) and without antibiotics negative control (NC). Group A and C showed significantly (p<0.05) higher feed intake (FI) as compared to other groups. Group C showed significantly (p<0.05) lower Total bacterial count (TBC) followed by group B as compared to NC. Carcass characteristics showed non-significant effects among different treatments. Mean villi length and width were significantly (p <0.05) higher in all ginger supplemented groups as compared to the control groups. Blood serum parameters including cholesterol, triglycerides, and low density lipoproteins (LDL) were significantly (p<0.05) lower in groups B and C in comparison with the control groups. Whereas high-density lipoproteins (HDL) was significantly higher in group B as compared to the others. In conclusion, ginger supplementation @0.6% in the basal diet significantly improved growth performance and gut morphometry of broilers. It also showed a positive impact on cholesterol, triglycerides and gut microbes. Therefore, ginger could be a better substitute for antibiotic growth promoters.(AU)

O presente estudo teve como objetivo determinar os efeitos de diferentes níveis de Zingiber officinale como aditivo à base de plantas medicinais sobre o desempenho de crescimento, características da carcaça, bioquímica sérica, contagem bacteriana total (CBT), morfologia intestinal e parâmetros imunológicos de frangos de corte. Um total de 1.500 pintos de corte de um dia de idade (Hubbard) foram igualmente credenciados em cinco grupos de tratamento, cada um com seis repetições (50 aves/repetição). Cinco dietas experimentais foram preparadas usando dieta basal, ou seja, com controle positivo de antibióticos (PC), 3 g/kg de gengibre (grupo A), 6 g/kg de gengibre (grupo B), 9 g/kg de gengibre (grupo C) e sem controle negativo de antibióticos (NC). Os grupos A e C apresentaram consumo de ração (FI) significativamente (p < 0,05) maior do que os outros grupos. O grupo C apresentou contagem bacteriana total (CBT) significativamente menor (p < 0,05) seguido pelo grupo B em comparação com o NC. As características da carcaça apresentaram efeitos não significativos entre os diferentes tratamentos. O comprimento e largura médios das vilosidades foram significativamente (p < 0,05) maiores em todos os grupos suplementados com gengibre em comparação com os grupos de controle. Os parâmetros séricos do sangue, incluindo colesterol, triglicerídeos e lipoproteínas de baixa densidade (LDL), foram significativamente (p < 0,05) menores nos grupos B e C em comparação com os grupos controle. Enquanto as lipoproteínas de alta densidade (HDL) foram significativamente maiores no grupo B em comparação com os outros. Em conclusão, a suplementação de gengibre a 0,6% na dieta basal melhorou significativamente o desempenho de crescimento e a morfometria intestinal de frangos de corte. Ele também mostrou um impacto positivo sobre o colesterol, triglicerídeos e micróbios intestinais. Portanto, o gengibre pode ser um substituto melhor para os promotores de crescimento com antibióticos.(AU)

The Protective Role of Silymarin to Ameliorate the Adverse Effects of Ochratoxin-A in Laying Hens on Productive Performance, Blood Biochemistry, Hematological and Antioxidants Status

This study was planned to examine the effect of silymarin on diminishing adverse effects of ochratoxin-A (OTA) in laying hens. A total number of 300 Inshas, local layer hens of 28 weeks of age were randomly distributed into 4 groups with 5 replicates each (15 hens). The birds were fed on the following treatments, (Control): fed a hen diet without any supplementation; (SL): fed the control diet supplemented with SL (1000 mg/kg feed); (OTA-diet): was fed the control diet contaminated with 1 ppm of OTA/kg diet, and (OTA+SL): fed the OTA-diet plus SL (1ppm OTA+1000 mg SL/kg feed). Results showed that feeding OTA at 1 ppm reduced productive performance compared with those fed the control diet. In OTA treated groups the total erythrocytes count, leukocytes count, PCV and Hb were decreased when compared to the control and SL groups. Albumin, globulin and serum total proteins in OTA treated groups were significantly lower when compared to the control and SL groups. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly increased in OTA fed groups in comparison with the control and SL groups. Creatinine and uric acid were increased in OTA treated groups but were almost normal in the SL group. The results showed that OTA had a severe effect on liver and kidney, but SL treated group had normal liver and kidneys showing its hepatoprotective effects.(AU)

Effects of broiler breeder age on immune system development of progeny

The objective of this study was to determine the effects that breeder age has on digestive and immune system development; the transfer of immunoglobulins to egg yolk, yolk sac, and neonate chicks; and the immune response of chicks up to 35 days old. Three ages (32, 42, and 52 weeks) of Hubbard breeders were studied with ages as treatments. A total of 425 eggs were weighed for each of the three treatments and incubated. After hatching, a total of 300 1-day-old chicks were used in each treatment. We studied the development of the gastrointestinal tract and immune system of progeny and IgY transfer from breeder to progeny. Chicks from 52-week-old breeders had greater gastrointestinal tract growth up to seven days of life and greater body weight at 14 days. Older breeders (52 weeks) had higher amounts of IgY in serum and egg yolk. Chicks from the youngest breeders (32-weeks-old) had a better immune response at two weeks post-vaccination. It can be concluded that the older breeders have a greater capacity to immunize progeny up to 14 days. Strategies can be developed to increase IgY in the serum of young breeders and, consequently, increase the innate immunity of the newly-hatched chicks.(AU)

Effects of Vitamin A and K3 on Immune Function and Intestinal Antioxidant Capacity of Aged Laying Hens

This study was conducted to investigate effects of vitamin A (VA) and vitamin K3 (VK3) on immune function and intestinal antioxidant capacity of aged laying hens. In a 3 × 3 factorial arrangement, the diets of 1080 Roman Pink laying hens (87 weeks old) was formulated with deficient, adequate and excess VA and VK3, including 0, 7000 and 14000 IU/kg VA and 0, 2.0 and 4.0 mg/kg VK3 for 8 weeks. Interactive effects between VA and VK3 were observed that VA and VK3 decreased the splenetic mRNA expression of inducible nitric oxide synthase (iNOS) and tumour necrosis factor α (TNF-α), but increased the plasma immunoglobulin G (IgG) content and jejunal mRNA expression of nuclear factor-like 2 (Nrf2). Hens fed adequate or excess VA had higher spleen index, mRNA expression of interleukin-10 (IL-10) in spleen, sIgA content, catalase (CAT), glutathione peroxidase and total dismutase (T-SOD) activity, and mRNA expression of polymeric immunoglobulin receptor (pIgR) in jejunum and lower mRNA expression of IL-1ß in jejunum and iNOS, TNF-α in spleen. Furthermore, adequate or excess VK3 significantly increased plasma IgG content, the CAT, T-SOD and total antioxidant capacity activities, up-regulated the mRNA expression of pIgR, Nrf2, SOD1 and CAT in jejunum and down-regulated the mRNA expression of iNOS and TNF-α in spleen.(AU)

Preliminary Study to Investigate the Effect of Lactobacillus Reuteri Administration on Growth Performance, Immunological, Gut Microbiome and Intestinal Mucosa of Chicken

The present study was conducted to investigate the efficacy of oral administration of L. reuteri on growth performance, intestine histomorphology, immunological and gut microbiome of broilers. A total of twenty healthy chickens were used in a five-week experimental trial. Birds were assigned into one of two groups with orally administrated L. reuteri probiotic and without probiotic- (Control -Phosphate-buffered saline). A significant (p<0.05) body weight gain was observed in the chickens in L. reuteri treatment group compare to those in the control group at the end of the trial. In addition, the serum IGF-1 cytokines level significantly enhanced in L. reuteri treatment group. However, there were no notable effects observed on the villus height, crypt depth, muscularis thickness, and submucosal thickness in chickens orally inject with and without L. reuteri. At the phylum level, the presence of Firmicutes (99.5%) was highly abundantin the L. reuteri treatment group. Moreover, the fecal microbial communities of Lactobacillus (99.9%) showed average relative abundance at genus level in L. reuteri treatment group. From this, we concluded that oral administration of L. reuteri would be beneficial to enhance the body weight gain, gut microbiome, and immune status of broiler.(AU)

Antimicrobial resistance profiles in Escherichia coli isolated from whole-chicken carcasses from conventional, antibiotic-free, and organic rearing systems / Perfil de resistência em Escherichia coli isoladas de carcaças de frango provenientes de sistemas de produção convencional, livre de antibióticos e orgânico

Antimicrobial resistance (AMR) is a growing concern in human and animal health. Public discussions on these issues have contributed to an increased demand for antibiotic-free food. Studies comparing the antimicrobial resistance profiles of bacteria in foodstuffs originating from farming systems with restrictions on the use of antimicrobials are scarce. This study aimed to assess the antimicrobial resistance profiles of generic Escherichia coli isolated from whole chickens originating from farming systems with and without restrictions on the use of antimicrobials. For this purpose, three groups of E. coli strains were formed: (GC) from chickens reared in conventional production systems, without restriction on the use of antimicrobials (n=72); (GL) from chickens reared in farming systems certified as free of any antibiotic use (n=72); and (GO) from chickens from an organic farming system (n=72). Whole chicken units were individually rinsed as recommended by ISO 17604:2015, and E. coli was isolated from the rinse suspension. To evaluate the resistance profile, E. coli strains were tested against 12 antimicrobials using broth microdilution or disk diffusion tests. Eighty strains (40.7%) were found to be fully susceptible to the tested antimicrobials, and 23.6% were multidrug resistant. The highest frequencies of resistance were observed to tetracycline (GC=37,5%; GL=34,7%; GO=25%) and trimethoprim (GC=27,8%; GL=34,7%; GO=22,2%). In the case of multidrug resistant strains, GC presented 32% (n=23) of strains with multidrug resistance characteristics whereas the GL and GO groups presented 22% (n=16) and 17% (n=12), respectively. As for the totally susceptible strains, a frequency of 56% of Tsus strains was observed in the organic group, whereas this frequency was 33% in the GC and GL groups. Using GC as a reference, the Poisson regression model showed a higher occurrence of fully susceptible E. coli strains, as well as lower frequencies of multidrug resistance and resistance to ampicillin and nalidixic acid in GO. The GL group exhibited the lowest frequency of ampicillin resistance. These observations suggest that the lower selection pressure for antimicrobial use in the farming system may be reflected in the resistance profile of bacteria present in foodstuffs purchased by consumers.(AU)

A resistência antimicrobiana (AMR) é uma preocupação crescente para a saúde humana e animal. A discussão pública dessas questões tem contribuído para o aumento da demanda por alimentos produzidos sem o uso de antibióticos. No entanto, estudos que comparem os perfis de resistência antimicrobiana de bactérias em alimentos oriundos de sistemas agrícolas com restrição ao uso de antimicrobianos ainda são escassos. O objetivo deste estudo foi avaliar o perfil de resistência antimicrobiana em Escherichia coli genérica isolada de carcaças de frangos inteiros oriundos de sistemas de criação com e sem restrições ao uso de antimicrobianos. Para tanto, três grupos de cepas de E. coli foram formados: (GC) isolados de carcaças de frangos criados no sistema convencional - sem restrição de uso de antimicrobianos (n=72); (GL) isolados de frangos de sistemas certificados sem uso de antimicrobianos (n=72); (GO) de frangos originados de produção orgânica (n=72). As unidades de frango inteiro foram submetidas à lavagem conforme recomendado pela ISO 17604: 2015 e E. coli foi isolada da suspensão de enxágue. Para avaliar o perfil de resistência, as cepas de E. coli foram testadas frente à 12 antimicrobianos pelos testes de microdiluição em caldo ou difusão em disco. Oitenta cepas (40,7%) foram totalmente suscetíveis aos antimicrobianos testados e 23,6% multirresistentes. As maiores frequências de resistência foram observadas frente a tetraciclina (GC=37,5%; GL=34,7%; GO=25%) e trimetoprima (GC=27,8%; GL=34,7%; GO=22,2%). No caso de cepas multirresistentes, GC apresentou 32% (n=23) das cepas com características de multirresistência enquanto os grupos GL e GO apresentaram 22% (n=16) e 17% (n=12), respectivamente. Quanto às cepas totalmente suscetíveis, foi observada uma frequência de 56% de cepas Tsus no grupo orgânico enquanto tal frequência foi de 33% nos grupos GC e GL. Utilizando GC como referência, o modelo de regressão de Poisson demonstrou maior ocorrência de cepas de E. coli totalmente suscetíveis, bem como menores frequências de multirresistência e resistência à ampicilina e ácido nalidíxico no GO. Em GL, apenas a frequência mais baixa de resistência à ampicilina pôde ser demonstrada. Essas observações sugerem que a menor pressão de seleção do uso de antimicrobianos no sistema de cultivo pode se refletir no perfil de resistência das bactérias presentes nos alimentos adquiridos pelo consumidor.(AU)

Rate of Transfer of Infectious Anaemia Maternal Antibodies from Broiler Breeders To the Progeny: a Field Evaluation

Clinical manifestation of the disease caused by the chicken anaemia virus (CAV) occurs when chicken chicks are vertically contaminated or before the second week of life. CAV control is based on the vaccination of broiler breeders in order to promote progeny protection through maternal antibodies. This work aims to evaluate, under field conditions, the antibody title in commercial broiler breeders at 28, 48, and 68 weeks of age, the rate of transference to the progeny, as well as the duration of antibodies in the progeny up to 21 days of age. Thus, a total of 92 sera samples from 93,000 broiler breeders vaccinated with a live vaccine for CAV at 14 weeks of age and 366 sera samples from their respective progeny were analyzed using ELISA. Breeders' antibody title for CAV ranged between 5051 and 8660, and these titles may provide sufficient protection for their progeny. On average, 63% of the maternal antibodies were transferred to the progeny and lasted up to the second week of chick's life. It is possible to conclude that the vaccine and the vaccination procedure used by this company for breeders against CAV seems to be effective in inducing high antibody levels in the breeders and transfering protective maternal antibodies to the progeny.(AU)

Enzyme-linked immunosorbent assay (ELISA) for detection of IgY Anti-Borrelia anserina antibodies in Gallus gallus domesticus / Ensaio de imunoadsorção enzimático (ELISA) indireto para detecção de anticorpos IgY Anti-Borreliaanserina em Gallus gallus domesticus

This study aimed to promote the standardization of an indirect, enzyme-linked immunosorbent assay (ELISA) for the serological detection of B. anserina in Gallus gallusdomesticus. An aliquoted sera from vaccinated chicken with B. anserina antigen (GI), experimental infected chickens with B. anserina (GII) and rustic poultry rearing of G. gallus (GIII) were tested with in-house ELISA developed to detect serum antibodies against B. anserina in G. gallus domesticus. On average, the experimentally infected chickens became positive at 9 DPI a mean ± standard deviation (SD) ODI value of 163.11 ± 70.65. The highest observed Optical Density Index (ODI) was 372.54 ± 132.39, at 26 DPI, and the highest overall ODI value was 626.51. The vaccinated chickens became positive between 8 and 10 DPV, with an ODI of 245.59 at 10 DPV, with an overall maximum ODI of 543.13. A total of 108 blood samples were collected from poultry raised on rustic farms. Of the total samples collected, 58.33% (63/108) were considered positive for B. anserina. The maximum ODI found among these rustic chickens was 283.24. This stardardization provided a sensitivity and specificity of 100%.

Este estudo teve como objetivo promover a padronização de um ensaio imunoenzimático indireto (ELISA) para a detecção sorológica de Borrelia anserina em Gallus gallus domesticus. Um frango vacinado com antígeno de B. anserina (GI), frangos infectados experimentalmente com B. anserina (GII) e frangos criados de forma rústica (GIII) foram testados com ELISA indireto in house desenvolvido para a detecção sorológica contra B. anserina em G. gallus domesticus. Em média, os frangos infectados experimentalmente tornaram-se positivos aos 9º dia pós-inoculação (DPI), um valor do índice de densidade óptica (ODI) médio ± desvio padrão (SD) de 163,11 ± 70,65. O maior ODI observado foi 372,54 ± 132,39, em 26ºDPI, e o maior valor geral de ODI foi 626,51. Os frangos vacinados tornaram-se positivos entre 8º e 10° DPV, com um ODI de 245,59 a 10 DPV, com um ODI máximo geral de 543,13. Um total de 108 amostras de sangue foram coletadas de aves criadas em fazendas rústicas. Do total de amostras coletadas, 58,33% (63/108) foram consideradas positivas para B. anserina. O ODI máximo encontrado entre essas galinhas rústicas foi 283,24. Essa padronização proporcionou sensibilidade e especificidade de 100%.

Bacillus coagulans as an alternative to antibiotics in the performance and control of Salmonella Enteritidis in broilers / Bacillus coagulans como alternativa aos antibióticos sobre o desempenho e controle da Salmonella Enteritidis em frangos de corte

The use of antimicrobial growth promoters in broiler feed has been beneficial for improving performance and preventing diseases. However, the indiscriminate use of these products in the feed can result in the development of resistant bacteria, the accumulation of residues in the products, and an imbalance in the microflora of birds. Therefore, it is necessary to evaluate alternatives, such as beneficial microorganisms that improve microbial growth without affecting animal health and product quality. This research aimed to evaluate the supplementation with the probiotic Bacillus coagulans on the performance, carcass characteristics, and health of broilers from seven to 42 days. In total, 720 broilers were used, distributed in a randomized block design with six treatments and eight replicates. The evaluated treatments were as follows: Control ration (RC); PROB1 (Probiotic 400 g/t); PROB2 (Probiotic 400 g/t until 21 days and 200 g/t from 22 to 42 days); RC + antibiotic; RC + Salmonella inoculation; PROB1 + Salmonella inoculation. The treatments did neither influence feed intake, carcass yield, and cuts nor the incidence of injuries to the chest, hock, and footpad. Weight gain and feed conversion were better in birds that received antibiotic or probiotic diets. There was an incidence of Salmonella in the challenges excreta at42 days only in the treatment with challenge without adding probiotics. We conclude that the probiotic Bacillus coagulans can be used as an alternative to antibiotics in the diet of broilers as it facilitates similar performance and is efficient in the control of Salmonella Enteritidis.

A utilização de promotores de crescimento antimicrobianos na alimentação de frangos de corte tem sido benéfica para melhoria do desempenho e para prevenção de doenças. Porém, o uso indiscriminado destes produtos nas rações pode resultar em desenvolvimento de bactérias resistentes, acúmulo de resíduos nos produtos e desequilíbrio da microflora das aves. Portanto, torna-se necessário avaliar alternativas como microrganismos benéficos que melhorem o crescimento microbiano, sem afetar a saúde do animal e a qualidade dos seus produtos. Objetivou-se com esta pesquisa avaliar a suplementação do probiótico Bacillus coagulans sobre o desempenho, características de carcaça e saúde de frangos de corte de 7 a 42 dias. Utilizou-se 720 frangos de corte distribuídos em delineamento em blocos casualizados, com seis tratamentos e oito repetições. Os tratamentos avaliados foram: Controle; PROB1 (Probiótico 400 g/t); PROB2 (Probiótico 400 g/ton até os 21 dias e 200 g/t dos 22 aos 42 dias); Controle + antibiótico; Controle + inoculação de Salmonella; PROB1 + inoculação de Salmonella. Os tratamentos não influenciaram o consumo de ração, rendimento de carcaça e cortes e a incidência de lesões no peito, jarrete e coxim plantar. O ganho de peso e a conversão alimentar foram melhores nas aves que receberam rações com antibiótico ou probiótico. Houve incidência de Salmonella nas excretas aos 42 dias somente no tratamento com desafio sem adição de probiótico. Conclui-se que o probiótico Bacillus coagulans pode ser usado como alternativa ao antibiótico na ração de frangos de corte, pois proporciona desempenho semelhante e é eficiente no controle da Salmonella Enteritidis

Systematic review of the use of phytobiotics in broiler nutrition / Revisão sistemática do uso de fitobióticos na nutrição de frangos de corte

The objective of this study was to conduct a systematic review of the literature on the use of phytogenics in broiler nutrition. A bibliographic survey was conducted for the years between 2009 and 2019, using the keywords “eubiotics,” “phytobiotics,” “essential oils,” “phytogenic extracts,” and corresponding wordsassociated with the terms “broiler” and “poultry.” The selected articles were grouped into the categories: animal performance, histomorphology of the intestinal wall, biochemical profile, carcass characteristics, and the effect on bacteria found in the intestine. After comparisons of several parameters on the use or non-use of phytogenics, it was found that replacing antibiotics with phytogenics contributes positively to performance, the histomorphology of the intestinal wall, the biochemical profile, carcass characteristics, and the number of bacteria found in the gut. In conclusion, based on several studies found in the literature, replacing antibiotics with phytogenic additives in broiler nutrition may be viable due to their lower residual impact on the final product, in addition to their positive effect on the parameters of animal production.

Objetivou-se realizar uma revisão sistemática da literatura sobre o uso de fitogênicos na nutrição de frangos de corte. Foi realizado levantamento bibliográfico do período de 2009 a 2019. Foram utilizadas as palavras-chave utilizadas foram “eubióticos”, “fitobióticos”, “óleos essenciais” e “extratos fitogênicos” e suas correspondentes em inglês, “eubiotics” e “phytobiotics”, “essential oils” e “phytogenic extracts”associada a palavra “frango de corte”, e “poultry” em inglês. Os artigos selecionados foram agrupados nas categorias: desempenho zootécnico, histomorfologia da parede intestinal, perfil bioquímico do sangue, característica de carcaça e o efeito nas bactérias encontradas no intestino. Após comparações de diversos parâmetros sobre o uso ou não uso de fitogênicos, percebeu- se que a substituição dos antibióticos pelos fitogênicos pode ser considerado positiva para o desempenho, histomorfologia da parede intestinal, perfil bioquímico do sangue, característica de carcaça e número de bactérias encontradas no intestino. Sendo assim, foi concluído com base nos diversos trabalhos encontrados na literatura que a substituição dos antibióticos pelos aditivos fitogênicos na nutrição de frangos de corte pode ser viável, devido ao seu menor impacto residual no produto final, além de influenciar positivamente nos parâmetros de produção animal.

Innate immunity in chicken lines developed by EMBRAPA Suínos e Aves: antimicrobial activity of macrophages and serum

The objective of this study was to compare the antimicrobial activity of macrophages and serum in laying hen (MM, CC, and CCc) and broiler chicken lineages (TT and LL). Macrophages were evaluated for phagocytic and antimicrobial activity. Microbicidal serum activity was evaluated by the resistance test for serum and the agar test. The results showed that phagocytic activity was higher in males of the MM strain, with 13% of macrophages presenting phagocytosis, while the other lineages studied, and even female MM, presented a rate of 6% of phagocytic cells. However, antimicrobial activity in macrophages from males of CCc lineage and females of TT lineage were higher, eliminating more than 30% of the Salmonella enterica inoculum, while in the other strains, the results were similar, with inoculum reduction below 30%. In the serum resistance assay, female laying lines presented higher antibacterial activity than female broiler lines. In the trials to evaluate the microbicide activity of the serum, females of both broiler and laying lineages presented higher performance when compared with males of the same lineage. Females of laying hen lines (MM and CC) present a greater antibacterium activity than males. These results can contribute to a better understanding of the immune response in broiler chicken and laying hen lineages, to aid development of lineages of birds more resistant to pathogens.

Performance and immune response of broilers born to breeders of different ages and fed different valine levels

Two experiments were carried out to evaluate the effects of digestible valine supplementation in pre-starter and starter diets on the productivity, nutrient metabolizability coefficient (NMC), and immune response of broilers from breeders of different ages. Experiments I and II were conducted with broilers in the pre-starter (1 to 7 days of age) and starter (8 to 21 days of age) phases, respectively. Broilers were fed diets that differed in their digestible valine content. In each trial, 400 male Cobb 500® chicks were randomly housed in a 2 × 4 factorial arrangement with eight treatments and five replicates of 10 birds each. The main effects were breeder age (37 vs. 52 weeks) and the digestible valine level in pre-starter (9.2, 10.2, 11.2, and 12.2 g/kg) and starter (8.3, 9.3, 10.3, and 11.3 g/kg) diets. Productive performance, intestinal histology, and immune response of broilers were evaluated. Supplementation with 11.2 g/kg valine in pre-starter diets improved NMC and increased villus height and villus:crypt ratio in the duodenum, jejunum development, and lymphocyte proliferation in the spleen of broilers at seven days of age, without improving performance (body weight gain, feed intake, and feed conversion ratio). In the starter phase, valine supplementation reduced feed intake but did not affect NMC, intestinal development, or immune response. The present results suggest that the same level of digestible valine should be used in the diet of broilers born to breeders of different ages, and the use of 9.2 and 8.3 g/kg digestible valine in pre-starter and starter diets, respectively, is sufficient to ensure satisfactory broiler performance. However, to improve the duodenum and jejunum development and immune response of broilers in the pre-starter phase, higher digestible valine levels are required.

Systematic review of the use of phytobiotics in broiler nutrition / Revisão sistemática do uso de fitobióticos na nutrição de frangos de corte

The objective of this study was to conduct a systematic review of the literature on the use of phytogenics in broiler nutrition. A bibliographic survey was conducted for the years between 2009 and 2019, using the keywords “eubiotics,” “phytobiotics,” “essential oils,” “phytogenic extracts,” and corresponding wordsassociated with the terms “broiler” and “poultry.” The selected articles were grouped into the categories: animal performance, histomorphology of the intestinal wall, biochemical profile, carcass characteristics, and the effect on bacteria found in the intestine. After comparisons of several parameters on the use or non-use of phytogenics, it was found that replacing antibiotics with phytogenics contributes positively to performance, the histomorphology of the intestinal wall, the biochemical profile, carcass characteristics, and the number of bacteria found in the gut. In conclusion, based on several studies found in the literature, replacing antibiotics with phytogenic additives in broiler nutrition may be viable due to their lower residual impact on the final product, in addition to their positive effect on the parameters of animal production.(AU)

Objetivou-se realizar uma revisão sistemática da literatura sobre o uso de fitogênicos na nutrição de frangos de corte. Foi realizado levantamento bibliográfico do período de 2009 a 2019. Foram utilizadas as palavras-chave utilizadas foram “eubióticos”, “fitobióticos”, “óleos essenciais” e “extratos fitogênicos” e suas correspondentes em inglês, “eubiotics” e “phytobiotics”, “essential oils” e “phytogenic extracts”associada a palavra “frango de corte”, e “poultry” em inglês. Os artigos selecionados foram agrupados nas categorias: desempenho zootécnico, histomorfologia da parede intestinal, perfil bioquímico do sangue, característica de carcaça e o efeito nas bactérias encontradas no intestino. Após comparações de diversos parâmetros sobre o uso ou não uso de fitogênicos, percebeu- se que a substituição dos antibióticos pelos fitogênicos pode ser considerado positiva para o desempenho, histomorfologia da parede intestinal, perfil bioquímico do sangue, característica de carcaça e número de bactérias encontradas no intestino. Sendo assim, foi concluído com base nos diversos trabalhos encontrados na literatura que a substituição dos antibióticos pelos aditivos fitogênicos na nutrição de frangos de corte pode ser viável, devido ao seu menor impacto residual no produto final, além de influenciar positivamente nos parâmetros de produção animal.(AU)

Active Surveillance and Risk Assessment of Avian Influenza Virus Subtype H9 from Non-Vaccinated Commercial Broilers of Pakistan

A cross-sectional study was conducted to investigate seroprevalence and virus prevalence of the H9 subtype of avian influenza virus in non-vaccinated broiler farms of dense poultry-populated districts, Lahore and Sheikhupura of Punjab-Pakistan. A convenient sampling method was adopted for collection of blood (n=500) and oropharyngeal swab (n=500) samples from 25 broiler farms of each district for hemagglutination inhibition assay and RT-PCR test, respectively. Proportional estimates were calculated using R software and overall seroprevalence of H9 was estimated at 36.3% (95% CI 33.3-39), with no significant difference (p>0.05) between Lahore (37.2 %, 95% CI=31.2-39.59) and Sheikhupura (35.4%, 95% CI= 29.64-39.76). RT-PCR identified 2% (4/200) pool level viral prevalence. None of the farms from Lahore districts were RT-PCR positive for H9. Simple logistic regression followed by multivariable analysis, identified the presence of foot bath/dipping area at the entrance (OR=0.7, 95% CI=0.52-0.93) and availability of rubber shoes for visitors (OR=0.36, 95% CI 0.26-0.48) as protective factors. History of respiratory signs (OR=1.51, 95%=CI 1.12-2.04), history of sudden death in past flocks (OR=3.26, 95% CI=2.41-4.41), and birds previously infected with avian influenza virus (OR=1.33, 95% CI=1-1.76) were significant risk factors. Negligence in preventive measures at farms level was associated with the spread of H9 infection between the farms. To control future outbreaks, biosecurity and continuous monitoring of non-vaccinated flocks are suggested.(AU)