Synergistic Effects of Hydroxychloride and Organic Zinc on Performance, Carcass Characteristics, Liver and Tibia Mineral Profiles of Broiler Chickens.

This study investigated the potential synergism between hydroxychloride and organic zinc (Zn) at different levels on performance and carcass characteristics of broiler chickens. There were seven experimental diets including a negative control diet without any supplemental Zn, and six diets with 80 mg/kg added Zn in the forms of ZnSO4, hydroxychloride Zn (HCZ) and organic Zn (ORZ), and a combination of HCZ and ORZ at 40 mg/kg HCZ + 40 mg/kg ORZ (HCZ40-ORZ40), 55 mg/kg HCZ + 25 mg/kg ORZ (HCZ55-ORZ25), and 70 mg/kg HCZ + 10 mg/kg ORZ (HCZ70-ORZ10). Each diet was replicated eight times with 17 chicks per replicate. On day 35, HCZ70-ORZ10 and HCZ40-ORZ40 diets resulted in the highest body weights (P < 0.05). Throughout the entire production period (1-35 days), all HCZ and ORZ diets significantly improved feed conversion ratio (FCR) compared to PC (P < 0.05), with HCZ40-ORZ40 showing the lowest FCR. Breast meat yield was lower in NC-fed birds, while HCZ80 and HCZ70-ORZ10 groups had the lowest abdominal fat weight (P < 0.05). Liver and gizzard weight, tibia breaking strength, and ash percentage, footpad dermatitis, and hock burns were not affected. Tibia Zn content was higher in HCZ or ORZ-supplemented birds compared to NC (P < 0.05), whereas other minerals in tibia and liver were unaffected. In summary, the absence of supplemental Zn negatively affects growth and carcass characteristics, whereas replacing ZnSO4 with HCZ, ORZ, or their combinations improves bodyweight and FCR. HCZ70-ORZ10 and HCZ40-ORZ40 were identified as optimal combinations for maximizing feed efficiency.

Effects of cassava root meal on the growth performance, apparent nutrient digestibility, organ and intestinal indices, and slaughter performance of yellow-feathered broiler chickens.

With the global population growth and shortage of food, the competition between humans and animal for food will become increasingly fierce. Therefore, the development of unconventional energy feed cassava feed is of great significance. The objective of this study was to investigate the effects of cassava root meal (CRM) on the growth performance, apparent digestibility, and organ and intestinal indices of broiler chickens. A total of 140 one-day-old chicks were randomly assigned to four dietary treatment groups [control diet (CT), 15% CRM (CRM15), 30% CRM (CRM30), and 45% CRM (CRM45)] with five replicates of seven birds per replicate. The results showed that the body weight of broiler chickens fed diets containing CRM were significantly lower than that in the CT group at 21 and 42 days of age, the average daily gain and average daily feed intake in the CRM group were significantly lower than those in the CT group from 1 to 21 days of age. However, from days 22 to 42, there were no significant differences between CRM15 and CT birds regarding average daily gain and average daily feed intake. but there was no difference in feed conversion rate between the CRM15 and CT groups. At 42 days of age, there were no significant differences between CRM15 and CT birds in in body measurements, the slaughter performance and the percentage of semi-eviscerated yield. The addition of CRM reduced the proportion of breast and thigh muscles during the feeding period, although we detected no significant difference between CRM15 and CT regarding the apparent digestibility of nutrients. Collectively, our findings indicate that 15% cassava was the optimal proportion for supplementing diets for broiler chicken production.

The anticoccidial effects of probiotics and prebiotics on the live coccidia vaccine and the subsequent influence on poultry performance post-challenge with mixed Eimeria species.

Live vaccines containing Eimeria oocysts are commercially available to protect against avian coccidiosis. Additionally, probiotics (PRO) and prebiotics (PRE) improve the poultry productivity and health and can be used as anticoccidial substitutes. However, the impact of PRO and PRE on reproductive potential, lesion score, intestinal health, and immunization outcomes of the live coccidia vaccines has not received adequate attention. Five groups of unsexed 1-day-old broiler chicks were used as follows: negative control (NC); challenged control (CC); vaccinated and challenged (VC); vaccinated, PRO-treated, and challenged (V-PRO); and vaccinated, PRE-treated, and challenged (V-PRE). At 21 d post-vaccination (pv), the vaccine increased the count of cecal anaerobes (P ≤ 0.05) and coliforms (P > 0.05) as well as harmed body weight gain (WG) (P ≤ 0.05), cecal lactic acid bacteria (P ≤ 0.05), and plasma carotenoid level (P > 0.05). None of the additives decreased oocyst shedding after vaccination, although they lowered the middle intestine and cecal lesion scores (P > 0.05). Compared to VC (2.68 ± 0.12) and V-PRE (2.66 ± 0.05), the V-PRO group showed an improved carotenoid level pv (2.96 ± 0.05) (P ≤ 0.05). V-PRE exhibited higher WG (822.95 ± 18.25) (P > 0.05) and FI (1153.01 ± 10.02) (P ≤ 0.05) than VC (781.86 ± 25.16 and 1109.85 ± 33.68) and V-PRO pv (787.61 ± 19.92 and 1077.43 ± 15.99). Following the homologous coccidia challenge, coccidia-vaccinated broilers adminstered the PRO or PRE continued to exhibit protection levels comparable to those received the vaccine alone. During 2 weeks post-challenge, VC, V-PRO and V-PRE improved bird performance and reduced oocyst shedding and lesion scores compared to CC. Ultimately, PRO and PRE treatments did not significantly reverse the reduction in growth performance in broiler chickens vaccinated against coccidia during the 1st three weeks of age.

Family flock size and age-sex structure of indigenous village chickens.

BACKGROUND: Indigenous village chickens (IVCs) significantly contribute to rural development. There is considerable variation in family flock size and age-sex structure of IVCs. OBJECTIVES: This study reports the family flock size, age-sex group structure, and demographic history of IVCs. METHODS: This work involved a cross-sectional study conducted using face-to-face general informants' individual interviews with 119 smallholder farmers in highland and lowland agroecological zones. RESULTS: The average family flock size of the sampled households was small (mean = 7.28, range: 1-38). Female birds (hens and pullets) represented the largest proportion of the family flocks (50.2%). The proportion of chicks (26.4%) and pullets (14.4%) was lower than that of hens (35.8%), which creates a considerable challenge in producing replacement breeding flocks. Similarly, the proportion of cockerels (9.1%) was lower than that of cocks (14.3%). The average cock-to-hen ratio (one cock to seven hens) was better than the commonly recommended proportion (1 cock to 8-10 hens). As a result, smallholder farmers have not faced the problem of producing infertile eggs. The estimated effective population size (Ne) of 4.02 and the corresponding inbreeding coefficient of 0.12 at the family flock level show that to some extent inbreeding may occur at the family flock level; besides, the estimated Ne represents 55.2% of the census size. However, inbreeding could be offset by the high rate of flock turnover and uncontrolled mating among scavenging birds. CONCLUSIONS: Family flocks contain a few birds, which may lead to consanguineous mating. Inbreeding is, however, considerably reduced by uncontrolled breeding among birds that share a common scavenging ground. The driving factors behind the low proportion of chicks and juvenile birds and the family flock size need to be further investigated to improve the contribution of local chickens to rural livelihoods.

Effects of cinnamon, rosemary and oregano on growth performance, blood biochemistry, liver enzyme activities, excreta microbiota and ileal morphology of Campylobacter jejuni-challenged broiler chickens.

BACKGROUND: Phytogenic additives would be helpful to mitigate the detrimental impact of Campylobacter jejuni on broiler chickens. OBJECTIVE: The experiment aimed to assess the effects of cinnamon, rosemary and oregano powder on physiological responses of broiler chickens challenged with C. jejuni from 0 to 42 days of age. METHODS: A total of 192 one-day-old male broiler chickens were divided into 6 treatment groups. The treatments included: negative control (NC; basal diet without additives and no C. jejuni challenge), positive control (PC; basal diet with C. jejuni challenge), PC with cinnamon, rosemary or oregano powder (3 g/kg each), and PC with Erythromycin (55 mg/kg). Except for the NC group, all chicks were orally challenged with 2 × 108 CFU/mL C. jejuni daily from days 21-25. Feed intake, body weight gain (BWG), feed conversion ratio (FCR), energy efficiency ratio (EER) and protein efficiency ratio (PER) were assessed during the rearing period (0-42 days). On day 42 of age, fresh excreta samples were collected from each pen to determine apparent dry matter digestibility and excreta microbiota. In addition, at the end of the experiment, blood samples were collected to evaluate blood profile and liver enzyme activities. RESULTS: C. jejuni challenge (PC treatment) decreased BWG, EER and PER, while increasing FCR of broiler chickens (p < 0.05), whereas rosemary, oregano and Erythromycin improved these performance parameters akin to NC. PC diet showed negative effect in ileal morphology, alleviated by additives except cinnamon (p < 0.05). Dietary additives successfully reduced Campylobacter levels and increased Lactobacilli counts in the PC. Rosemary and oregano lowered plasma total cholesterol (p < 0.05). Alanine aminotransferase elevation by C. jejuni challenge in the PC group was prevented by rosemary, oregano and Erythromycin (p < 0.05). CONCLUSIONS: Oregano and rosemary alleviate the impact of C. jejuni challenge.

ESBL Producing E. coli in Chickens and Poultry Farms Environment in Selangor, Malaysia: A Cross-Sectional Study on Their Occurrence and Associated Risk Factors With Environment and Public Health Importance.

INTRODUCTION: Extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) are widespread multidrug-resistant zoonotic bacteria that threaten animal production, food safety and antimicrobial therapy worldwide including Malaysia. Poultry has been reported as one of the pathways for human exposure to ESBL-EC. There has been little research on the occurrence of ESBL-EC within the Malaysian poultry food chain. Hence, the objectives of the study were to determine the occurrence of ESBL-EC in chickens and to identify the potential risk factors associated with their occurrence in poultry farms. METHODS: A cross-sectional study was conducted on 400 samples, consisting of 240 cloacal swabs from chickens and 160 from poultry farms environments in eight districts in Selangor, Malaysia using culture and disk combination methods and multiple polymerase chain reaction assays. In the determination of possible factors associated with the presence of ESBL-EC at poultry farms, a questionnaire was used to obtain the information and data. RESULTS: The findings demonstrated the wide distribution of ESBL-EC in all the farms with an overall occurrence of 37.2%. Farms in Gombak, Klang and Hulu Selangor had the highest occurrence rates at 62%, 50% and 50%, respectively, followed by farms in Petaling 38%, Sepang at 34%, Kuala Langat at 26% and Kuala Selangor at 24%, and the lowest was in Hulu Langat 14%. Among the study samples, chickens had the highest occurrence rate at 45.4%, followed by chicken house floors at 40% and flies at 30%, while feed and water samples at 17.5% and 12.5%, respectively. The present study indicated the high occurrence and wide dissemination of ESBL-EC in chickens and poultry farms environment. The ESBL-EC occurrence was associated with several factors including imprudent use of antibiotics, poor husbandry, management and biosecurity practices at the farms. CONCLUSIONS: Our study showed the presence and spread of ESBL EC among chickens in the farms and their environment; this may lead to being spread to outside of farm environment by flies, vermins, flying birds, litter and farm wastes and possibly to humans upon contact with the contaminated environment and by poultry meat. Thus, the findings of the study can assist to serve as a piece of useful information to veterinary authority in designing evidence-based mitigation strategies for the control of ESBL-EC in poultry farms.

Dynamic response of the intestinal microbiome to Eimeria maxima-induced coccidiosis in chickens.

Eimeria maxima is a major cause of coccidiosis in chickens and a key predisposing factor for other economically significant diseases such as necrotic enteritis. However, a detailed understanding of the intestinal microbiome response to E. maxima infection is still lacking. This study aimed to comprehensively investigate the dynamic changes of the intestinal microbiome for 14 days post-infection (dpi) with E. maxima. Bacterial 16S rRNA gene sequencing was performed with the ileal and cecal digesta collected from mock and E. maxima-infected chickens at the prepatent (3 dpi), acute (5 and 7 dpi), and recovery phases (10 and 14 dpi) of infection. Although no notable changes were observed at 3 dpi, significant alterations of the microbiota occurred in both the ileum and cecum at 5 and 7 dpi. By 14 dpi, the intestinal microbiota tended to return to a healthy state. Notably, Lactobacillus was enriched in response to E. maxima infection in both the ileum and cecum, although individual Lactobacillus, Ligilactobacillus, and Limosilactobacillus species varied in the temporal pattern of response. Concurrently, major short-chain fatty acid-producing bacteria, such as Faecalibacterium, were progressively suppressed by E. maxima in the cecum. On the other hand, opportunistic pathogens such as Escherichia, Enterococcus, and Staphylococcus were significantly enriched in the ileum during acute infection. IMPORTANCE: We have observed for the first time the dynamic response of the intestinal microbiota to Eimeria maxima infection, synchronized with its life cycle. Minimal changes occur in both the ileal and cecal microbiota during early infection, while significant alterations coincide with acute infection and disruption of the intestinal mucosal lining. As animals recover from coccidiosis, the intestinal microbiota largely returns to normal. E. maxima-induced intestinal inflammation likely creates an environment conducive to the growth of aerotolerant anaerobes such as Lactobacillus, as well as facultative anaerobes such as Escherichia, Enterococcus, and Staphylococcus, while suppressing the growth of obligate anaerobes such as short-chain fatty acid-producing bacteria. These findings expand our understanding of the temporal dynamics of the microbiota structure during Eimeria infection and offer insights into the pathogenesis of coccidiosis, supporting the rationale for microbiome-based strategies in the control and prevention of this condition.

Polymelia and concurrent intestinal duplication and cloacal atresia in a broiler chick: case report and literature review.

Congenital malformations are a highly diverse group of conditions reported in both humans and animals, characterized by defects in morphogenesis observed at birth. Although most cases are idiopathic, genetic and environmental factors may be involved. The frequency of such conditions varies with species, geographic regions, and the specific malformation involved. In polymelia, supernumerary limbs are attached to different parts of the body. Gastrointestinal duplications are described less frequently and can be associated with polymelia. Cloacal atresia is among the least-reported malformations in avian species, described only once in a kiwi. Here we describe a case with these 3 malformations in a single broiler chick (Gallus gallus domesticus) and provide a literature review about the occurrence of these malformations in birds. The 3-d-old chick also had an unidentified structure projecting from the pygostyle region. We performed clinical, radiographic, and postmortem examinations. The intestinal duplication was identified only during the postmortem evaluation. Detailed descriptions of avian congenital malformations are scarce. Although similar cases have been reported, we retrieved no cases of concurrent polymelia, intestinal duplication, and cloacal atresia in broiler chickens in our literature search, suggesting that the simultaneous occurrence of these conditions has not been reported previously in this species.

Single nucleus/cell RNA-seq of the chicken hypothalamic-pituitary-ovarian axis offers new insights into the molecular regulatory mechanisms of ovarian development.

The hypothalamic-pituitary-ovarian (HPO) axis represents a central neuroendocrine network essential for reproductive function. Despite its critical role, the intrinsic heterogeneity within the HPO axis across vertebrates and the complex intercellular interactions remain poorly defined. This study provides the first comprehensive, unbiased, cell type-specific molecular profiling of all three components of the HPO axis in adult Lohmann layers and Liangshan Yanying chickens. Within the hypothalamus, pituitary, and ovary, seven, 12, and 13 distinct cell types were identified, respectively. Results indicated that the pituitary adenylate cyclase activating polypeptide (PACAP), follicle-stimulating hormone (FSH), and prolactin (PRL) signaling pathways may modulate the synthesis and secretion of gonadotropin-releasing hormone (GnRH), FSH, and luteinizing hormone (LH) within the hypothalamus and pituitary. In the ovary, interactions between granulosa cells and oocytes involved the KIT, CD99, LIFR, FN1, and ANGPTL signaling pathways, which collectively regulate follicular maturation. The SEMA4 signaling pathway emerged as a critical mediator across all three tissues of the HPO axis. Additionally, gene expression analysis revealed that relaxin 3 (RLN3), gastrin-releasing peptide (GRP), and cocaine- and amphetamine regulated transcripts (CART, also known as CARTPT) may function as novel endocrine hormones, influencing the HPO axis through autocrine, paracrine, and endocrine pathways. Comparative analyses between Lohmann layers and Liangshan Yanying chickens demonstrated higher expression levels of GRP, RLN3, CARTPT, LHCGR, FSHR, and GRPR in the ovaries of Lohmann layers, potentially contributing to their superior reproductive performance. In conclusion, this study provides a detailed molecular characterization of the HPO axis, offering novel insights into the regulatory mechanisms underlying reproductive biology.

Characterization of the Coding Sequence of the MC1R (Melanocortin 1 Receptor) Gene of Ayam Cemani Black Chickens.

Plumage color is one of the most important traits characterizing chicken breeds. Black-boned chickens constitute a specific group of breeds with a unique phenotype. One of the representatives is the Indonesian Ayam Cemani. The extraordinary black phenotype results from a specific chromosomal rearrangement. We used complete CDS of crucial color-related gene MC1R, which plays a key role in melanin distribution but has not been previously studied in Ayam Cemani. It turned out that Ayam Cemani individuals possess a newly found non-synonymous mutation G355A resulting in amino acid substitution D119N. Together with the presence of G274A (E92K), the new missense variant enabled us to distinguish a new extended black allele at the E locus. All of the investigated birds were heterozygous in terms of the new mutation. Previous studies and our own results indicate a high level of genetic variation within the MC1R gene within and between chicken breeds. Besides the key mutations that make it possible to distinguish particular major alleles, there are also numerous substitutions that give haplotypes more characteristics for individual breeds.

Preparation, Structural Analysis, and Growth-Promoting Effects of Amomum longiligulare Polysaccharide 1-Mg (II) Complex.

In this study, Amomum longiligulare polysaccharide 1 (ALP1) is used to chelate with magnesium (Mg) to synthesize the ALP1-Mg (II) complex (ALP1-Mg). Based on Box-Behnken response surface design, the optimum technological conditions are 22 mg mL-1 trisodium citrate, 2.10 mol L-1 MgCl2, reaction at 70 °C for 2.9 h, resulting in a maximum Mg content of 2.13%. Next, the physicochemical properties and structural characteristics of ALP1 and ALP1-Mg are characterized, and the results show that the morphology, conformation, crystallinity, and thermal stability of ALP1-Mg are changed. In addition, dietary supplementation of 500 mg kg-1 ALP1-Mg significantly reduces the feed conversion ratio during the grower (15-35 d). Meanwhile, the villus height/crypt depth of the duodenum and ileum are significantly increased, and the relative abundance of Lactobacillus is significantly elevated. Taken together, the results suggest that ALP1-Mg is a potential growth-promoting feed additive.

Impact of different range areas on behavior, welfare, and performance of Naked Neck chickens.

This study aimed to evaluate the effect of different environmental enrichment tools on behavior, welfare, productive performance, and egg quality traits of Naked Neck chickens. A total of 1080 Naked Neck female chickens (30 weeks old) were used in the present study. A completely randomized experimental design, with 3 treatments having 4 replicates of 90 birds each, was applied. Treatments consisted of 3 different range areas A (121.9 m2), B (152.4 m2), and C (190.5 m2). Behavior (walking, feeding/foraging, sitting, aggressiveness wing flapping, perching, dust bathing, and range use), welfare (foot pad dermatitis, lameness, gait score, and feather pecking), productive performance (egg weight, egg production %, egg mass, and feed intake), egg quality traits (morphometry, egg weight, shell, albumen, and yolk characteristics) were evaluated. There was no influence (P > 0.05) of different range area on bird's behavior, and egg quality traits except walking and rang usage. The range area C promoted productive performance including egg weight, egg production %, egg mass and feed intake, but it did not influence welfare traits. It might be concluded that Naked Neck chicken when reared in free range with different range enrichments did not reveal any difference regarding behavioral parameters, egg morphometry, and egg quality traits. The range area within minimum length and effectively used environmental enrichments (perching and dust bathing area) should be used for backyard poultry to obtain ideal performance.

Comparative Effectiveness of Various Multi-Antigen Vaccines in Controlling Campylobacter jejuni in Broiler Chickens.

This study was undertaken to evaluate and compare the efficacy of different multi-antigen vaccines, including heat-inactivated, whole lysate, and subunit (outer membrane proteins [OMPs]) C. jejuni vaccines along with the immunostimulant CpG ODN in controlling Campylobacter colonization in chickens. In the first trial, 125 µg of C. jejuni OMPs and 50 µg of CpG ODN were administered individually or in combination, either in ovo to chick embryos or subcutaneously (SC) to one-day-old chicks. In the second trial, different concentrations of C. jejuni antigens (heat-killed, whole lysate, and OMPs) were administered SC to one-day-old chicks. The results of the first trial revealed that SC immunization with the combination of CpG ODN and C. jejuni OMPs elevated interferon (IFN)-γ, interleukin (IL)-1ß, and IL-13 gene expression in the spleen, significantly increased serum IgM and IgY antibody levels, and reduced cecal C. jejuni counts by approximately 1.2 log10. In contrast, in ovo immunization did not elicit immune responses or confer protection against Campylobacter. The results of the second trial showed that SC immunization with C. jejuni whole lysate or 200 µg OMPs reduced C. jejuni counts by approximately 1.4 and 1.1 log10, respectively. In conclusion, C. jejuni lysate and OMPs are promising vaccine antigens for reducing Campylobacter colonization in chickens.

Phytogenic cocktails fed in different feeding regimes as alternatives to antibiotics for improving performance, intestinal microbial, and carcass characteristics of slow growth chickens.

Background and Aim: The phytogenic cocktail (PC) is a unique combination of natural plant extracts consisting of coconut shell smoke, clove leaf extract, and mangosteen rind extract, predominantly containing phenol, eugenol, and α-mangostin. Chicken performance can be improved by its antibacterial properties. This study aimed to test PC as a replacement for antibiotic growth promoters (AGPs), assessing its impact on performance, intestinal microbes, and carcass traits in slow growth KUB chickens. Materials and Methods: Two hundred and forty KUB chicks were distributed randomly to five dietary groups. Each group constituted six replicates, one replicate contained eight chicks. The treatments included the control diet (CD) with no additives, CD with 50 ppm Zinc bacitracin as an additive (AGPs), CD paired with 198 mL PC/ton feed provided for the initial 12 weeks (PC1), CD with 198 mL PC/ton feed given for the first 4 weeks (PC2), and CD supplied with 198 mL PC/ton feed for the first 8 weeks (PC3). Performance and mortality indicators were assessed during the feeding stage up to 12 weeks of age, while intestinal total microbial count and carcass characteristics were determined at 12 weeks. Duncan's multiple-range test identified differences among the treatments in the randomized experiment. Results: The AGPs group weighed significantly more (p < 0.05) than PC2 but not significantly different (p > 0.05) from Control, PC1, and PC3 at 4 weeks. At 8 weeks, there was no significant difference (p > 0.05) in the body weight (BW) between the AGP, CD, and PC groups. The AGPs group had a significantly greater BW than PC1 and PC2 at 12 weeks (p < 0.05), but was comparable to CD and PC3 (p > 0.05). During the starter phase (0-4 weeks), dietary addition of AGPs or PCs significantly reduced feed intake (p < 0.05); however, no significant effect (p > 0.05) was observed during the later feeding periods (0-8 or 0-12 weeks). During the starter period, PC3 yielded the best feed conversion ratio, slightly surpassing AGPs and significantly (p < 0.05) outperforming CD. No significant variations (p > 0.05) were detected in the carcasses among the treatments. The reduction of abdominal fat relative weight was significant (p < 0.05) during the first 8 weeks of PC feeding. After the 12-week trial, no significant difference (p > 0.05) was observed in the proportionate weights of the crop, proventriculus, gizzard, pancreas, cecum, spleen, bursa of Fabricius, heart, and liver. The reduction in the intestinal microbe population due to AGPs or PC was not statistically significant (p > 0.05). About 100% viability was confirmed by the absence of mortality throughout the study. Conclusion: PC supplementation in KUB chicken feed enhances their performance. The optimal feeding regimes were effective during the first 8 weeks of age. In the 0-4 week time frame, feeding the PC to the chicken worsened performance whereas no improvement was observed in the 0-12 week period. The application enhanced weight loss, feed efficiency, and reduced abdominal fat. Based on the research findings, the PC can replace AGPs as a feed additive due to comparable or superior improvement results.

Prevalence of Cryptosporidium spp. infection in rodents and chickens in Franceville, Gabon.

Background and Aim: Cryptosporidium spp. members of the phylum Apicomplexa are obligate protozoan parasites capable of infecting various vertebrate hosts, including rodents and chickens. Infection caused by these parasites may lead to zoonotic diseases in humans. The aim of this study was to estimate the prevalence of Cryptosporidium spp. in rodents and domestic chickens sampled in Franceville, Gabon. Materials and Methods: Two hundred and eighty-five samples were collected, of which 185 samples were from rodents and 100 from domestic chickens. Microscopy after modified Ziehl-Neelsen staining and nested polymerase chain reaction targeting the small subunit (SSU) rRNA gene were used to examine Cryptosporidium spp. Results: The overall prevalence of Cryptosporidium oocysts was 55.8%, with a prevalence of 72.4% in rodents and 25.0% in domestic chickens. Molecular analysis showed that Cryptosporidium spp. were present in 4.0% of the samples. No significant correlation was observed between Cryptosporidium spp. carriage and sex or location in this study. These results indicate that Cryptosporidium spp. persist and circulate in the studied animal species in Franceville, Gabon. Conclusion: Infection with Cryptosporidium is very common in rodents and chickens in Franceville. The potential risk of human contamination cannot be ruled out. More research should be conducted to characterize Cryptosporidium species circulating in rodents and chickens in Gabon. Such studies are essential to better understand the epidemiology of this protozoan and its potential impact on public health.

Antigen specificity affects analysis of natural antibodies.

Natural antibodies are used to compare immune systems across taxa, to study wildlife disease ecology, and as selection markers in livestock breeding. These immunoglobulins are present prior to immune stimulation. They are described as having low antigen specificity or polyreactive binding and are measured by binding to self-antigens or novel exogenous proteins. Most studies use only one or two antigens to measure natural antibodies and ignore potential effects of antigen specificity in analyses. It remains unclear how different antigen-specific natural antibodies are related or how diversity among natural antibodies may affect analyses of these immunoglobulins. Using genetically distinct lines of chickens as a model system, we tested the hypotheses that (1) antigen-specific natural antibodies are independent of each other and (2) antigen specificity affects the comparison of natural antibodies among animals. We used blood cell agglutination and enzyme-linked immunosorbent assays to measure levels of natural antibodies binding to four antigens: (i) rabbit erythrocytes, (ii) keyhole limpet hemocyanin, (iii) phytohemagglutinin, or (iv) ovalbumin. We observed that levels of antigen specific natural antibodies were not correlated. There were significant differences in levels of natural antibodies among lines of chickens, indicating genetic variation for natural antibody production. However, line distinctions were not consistent among antigen specific natural antibodies. These data show that natural antibodies are a pool of relatively distinct immunoglobulins, and that antigen specificity may affect interpretation of natural antibody function and comparative immunology.

Clostridium perfringens antigens and challenges for development of vaccines against necrotic enteritis in poultry.

INTRODUCTION: Chickens with Necrotic Enteritis (NE), caused by Clostridium perfringens, exhibit acute and chronic symptoms that are difficult to diagnose, leading to significant economic losses. Vaccination is the best method for controlling and preventing NE. However, only two vaccines based on the CPA and NetB toxins have been commercialized, offering partial protection, highlighting the urgent need for more effective vaccines. OBJECTIVE: This review aimed to identify promising antigens for NE vaccine formulation and discuss factors affecting their effectiveness. METHODS: A systematic review using five scientific databases identified 30 eligible studies through the Rayyan tool, which were included for quality review. RESULTS: We identified 25 promising antigens, including CPA, NetB, FBA, ZMP, CnaA, FimA, and FimB, categorized by their role in disease pathogenesis. This review discusses the biochemical, physiological, and genetic traits of recombinant antigens used in vaccine prototypes, their expression systems, and immunization potential in chickens challenged with virulent C. perfringens strains. Market supply challenges, immunogenic potential, vaccine platforms, adjuvants, and factors related to vaccination schedules-such as administration routes, dosing intervals, and age at immunization-are also addressed. Additionally, the study notes that vaccine formulations tested under mild challenges may not offer adequate field-level protection due to issues replicating aggressive conditions, strain virulence loss, and varied methodologies. CONCLUSIONS: An ideal NE vaccine should incorporate multiple antigens, molecular adjuvants, and delivery systems via in ovo and oral routes. The review underscores the challenges in developing and validating NE vaccines and the urgent need for a standardized protocol to replicate aggressive challenges accurately.

Dietary advanced chelate technology-based 7-mineral supplement improves growth performance and intestinal health indicators during a mixed Eimeria challenge in broiler chickens.

The health and productivity of broilers may be improved by optimizing the availability and levels of trace minerals (TM) in their feed, especially in the presence of parasites. This study investigated the effects of replacing inorganic TM (ITM) with an advanced chelate technology-based 7 TM (ACTM) on performance, hematology, lesion score, oocyst shedding, gut morphology, and tight junction structure in broilers challenged with mixed Eimeria species. There were 480 1-day-old broiler chickens divided into 5 groups: uninfected negative control and recommended levels of ITM (NC); infected positive control and recommended levels of ITM (PC); or PC supplemented with salinomycin (SAL); PC diet with 50 % ACTM instead of ITM (ACTM50); or PC diet with 100 % ACTM instead of ITM (ACTM100). All groups, except NC, were orally challenged with mixed Eimeria spp. oocysts on day 14. Each group had 6 replicate cages, with 16 birds per replicate. The results showed that the NC, SAL, and ACTM100 groups had higher (P < 0.05) body weight, average daily gain (ADG), and European production efficiency index (EPEI), as well as a lower (P < 0.05) feed conversion, mortality rate, and heterophile to lymphocyte ratio compared to the PC group, with the NC group having the highest ADG and EPEI throughout the experiment. The SAL and ACTM100 groups had lower (P < 0.05) intestinal lesion scores and oocyst numbers compared to the PC group, although all coccidiosis-challenged groups had higher oocyst shedding compared to the NC group. On day 24, the challenged birds in the SAL and ACTM100 groups had higher (P < 0.05) villus height and surface area in the duodenum and ileum, as well as a higher (P < 0.05) villus height to crypt depth ratio in the jejunum. The expression levels of jejunal CLDN1 and ZO-1 were also higher (P < 0.05) in the ACTM100 and SAL groups compared to the PC and ACTM50 groups at 24 days of age. In conclusion, while using ACTM in broiler diets at 50 % of the commercial recommended levels maintained performance and physiological responses, complete replacement with ACTM improved growth performance and intestinal health characteristics, similar to salinomycin under Eimeria challenge conditions.

Molecular Detection of Respiratory Tract Viruses in Chickens at the Point of Need by Loop-Mediated Isothermal Amplification (LAMP).

Accurate and timely molecular diagnosis of respiratory diseases in chickens is essential for implementing effective control measures, preventing the spread of diseases within poultry flocks, minimizing economic loss, and guarding food security. Traditional molecular diagnostic methods like polymerase chain reaction (PCR) require expensive equipment and trained personnel, limiting their use to centralized labs with a significant delay between sample collection and results. Loop-mediated isothermal amplification (LAMP) of nucleic acids offers an attractive alternative for detecting respiratory viruses in broiler chickens with sensitivity comparable to that of PCR. LAMP's main advantages over PCR are its constant incubation temperature (∼65 °C), high amplification efficiency, and contaminant tolerance, which reduce equipment complexity, cost, and power consumption and enable instrument-free tests. This review highlights effective LAMP methods and variants that have been developed for detecting respiratory viruses in chickens at the point of need.

The Effect of Phytogenic Additive in Broiler's Diet on Production Results, Physicochemical Parameters, and the Composition of Volatile Organic Compounds of Broiler Meat Assessed by an Electronic Nose System.

The primary objective of this study was to investigate the impact of a phytogenic additive (PA) in broiler chickens' diet on production, physiochemical parameters, and the profile of volatile organic compounds present in broiler chickens' meat. The experiment was conducted in a commercial chicken house, where Ross 308 broiler chickens were divided into two groups, each consisting of 65,000 broilers. One group was fed a diet supplemented with 100 ppm of PA throughout the rearing period. The primary chemical composition of the meat and its physicochemical parameters were determined. A visual assessment of breast muscles for defects and volatile organic compounds were evaluated using an electronic nose system. No statistically significant differences were shown in the production performance of the chickens; while summarizing all production parameters, a higher EPEF index of 31 points in the experimental group was highlighted. Breast muscle quality showed differences in drip loss and WHC (p ≤ 0.01) in favor of the experimental group, and a lower cutting force value (p ≤ 0.05) was found for breast muscles from the experimental group. The group also had a lower proportion of muscles with a white striping defect, and the results of volatile organic compound profiling showed the most aroma units.