Jean Raphaël Kana

Aflatoxin B ₁ (AFB ₁ ) and ochratoxin A (OTA) are among the most prevalent mycotoxins affecting poultry production, particularly in developing countries where feed quality control is limited. Clay-based binders have been widely used to reduce mycotoxin bioavailability and tissue carry-over, but their high cost restricts their adoption by smallholder farmers. This study evaluated the efficacy of locally available natural unpurified halloysite-kaolinite (B) and smectite (G) rich clays in limiting the carry-over of AFB ₁ and OTA from contaminated feed to broiler tissues, and their effects on growth performance. A total of 432 day-old Cobb 500 broiler chicks were randomly allocated to nine dietary treatments with three replicates each. Treatments included six diets supplemented with natural clays at 1, 2, or 3 g/kg (B1-B3) and G1-G3), two diets containing commercial binders (aluminosilicate + yeast, AY; bentonite, Be), and a contaminated control diet without additive (T0). Experimental diets were naturally contaminated using mouldy groundnut cake containing >80 μ g/kg AFB ₁ and 45.2 μ g/kg OTA. Growth performance parameters were recorded over a 42-day period, and AFB ₁ and OTA residues were quantified in liver, gizzard, and muscle tissues. Compared with the untreated control, all clay-supplemented diets significantly improved body weight gain and feed conversion ratio. Natural clays induced moderate but significant reductions in AFB ₁ and OTA residues across tissues, with halloysite-kaolinite at 2 g/kg and smectite at 1 g/kg showing the most consistent effects. However, commercial binders, particularly bentonite, exhibited greater overall efficacy in reducing mycotoxin carry-over. These results indicate that natural unpurified halloysite-kaolinite and smectite clays can partially mitigate the adverse effects of AFB ₁ and OTA under realistic tropical contamination conditions. Although less effective than commercial binders, their local availability and low cost make them promising complementary strategies for mycotoxin risk management in poultry production systems in low-income countries.

Introduction: The use of antibiotics as growth promoters in animal husbandry has been banned due to concerns that antibiotic residues can accumulate in animal tissues and lead to bacterial resistance. The present study aimed to explore the effects of varying amounts of Cyperus alternifolius (C. alternifolius) rhizome powder on feed digestibility, growth performance, intestinal microbial flora, hemato-biochemical parameters, and immune responses in broiler chickens as an alternative to antibiotics. Materials and methods: An experiment was conducted at the Application and Research Farm of the University of Dschang (Cameroon) over 49 days. A total of 512 day-old broiler chickens, including 256 males and 256 females, were randomly assigned to eight treatment groups, with four replicates of 16 chickens each, with equal numbers from both sexes. The treatment groups included a negative control group which administered a basal diet without additive (NC), a basal diet containing 1 g of doxycycline/kg of feed as the positive control group (PC), and six diets containing the powder of C. alternifolius rhizome as a phyto-additive, at the dose of 1 g of C. alternifolius/kg of feed (T1), 2 g (T2), 4 g (T4), 6 g (T6), 8 g (T8) and 10 g (T10). The growth performance, carcass characteristics, microbial flora, feed digestibility, the immune system, and hematological and biochemical parameters were evaluated.Results: Live weight and weight gain increased by approximately 7.02% and 7.11%, respectively, in T4 compared with NC during the finisher phase. Feed conversion ratio was significantly reduced in T4 by approximately 11.05% compared to NC, but it was comparable to that of PC, T6, and T8. The number of lactobacilli and crude protein digestibility increased significantly in all treatment groups compared to NC. Furthermore, in T4, the number of Escherichia coli significantly decreased by 40.9% compared to NC, T1, T8, and T10. Besides the notable increase in total protein level in T4 compared with other groups, the hemato-biochemical parameters of the chickens showed no significant differences across groups.Conclusion: Cyperus alternifolius at a dose of 4 g/kg of feed demonstrated potential as an alternative to growth-promoting antibiotics, with diminished adverse effects on broiler chicken health.

Introduction: The ban on the use of antibiotics as feed additives in livestock farming has led to the development of alternative products. This study aimed to evaluate the effects of combining phytobiotic (Dichrostachys glomerata) with a probiotic (Thepax®) on the growth performance of Japanese quails. Results: The findings indicated that quails fed on 0.6 ml probiotic / L of drinking water had the highest weight gain and the lowest feed conversion ratio. Combining phytobiotic with probiotics at 0.4 ml and 0.5 ml improved the apparent digestibility of crude protein and organic matter. Although the treatment did not significantly affect the carcass yields, the relative weight of the liver and pancreas were lowest with 0.4 ml probiotic. Haemato-biochemical parameters increased with higher levels of probiotics combined with 4 g of phytobiotics in the feed, leading to an increase in serum content in ALT and creatinine. Combining 4 g of the phytobiotic with 0.6 ml of probiotic resulted in a decrease in pathogens (Salmonella and E. coli) count in the gastrointestinal tract of quails. Conclusion: The combination of Dichrostachys glomerata (4g /kg feed) to a probiotic (0.6ml /L drinking water) improved feed conversion ratio and live weight gain while reducing the pathogenic microorganisms in the gastrointestinal tract of Japanese quails.

Introduction: The global ban on antibiotics as a feed additive, prompted by concerns over microbial resistance and the accumulation of antibiotic residues in animal products, has urged researchers to explore natural alternatives. These alternatives modulate the gut microbiota and enhance animal production performance. This study aimed to assess the impact of Allium sativum on the production performance of broiler chickens. Materials and methods: A total of 280 day-old broiler chicks were examined for 42 days. After being sexed, they were randomly allocated into five groups, each consisting of 14 chicks, with four replications. The control group was fed on a ration without additives (R0-). The treatment groups consisted of a control diet supplemented with 1 g of antibiotic Doxycycline® per kg of basal diet and per liter of drinking water (R0+) and 5 g garlic per kg of basal feed and also per liter of drinking water (RAs), respectively. To facilitate the oral administration, the solution was absorbed by charcoal from the fruit stones of Canarium schweinfurthii at a rate of 100 g and 100 ml per kg of diet and per liter of drinking water, respectively. The investigated parameters included growth performance, microbial flora, markers of kidney, and liver function, and feed digestibility. Results: The results revealed Allium sativum significantly decreased feed intake, feed conversion ratio, serum aspartate aminotransferase, alanine aminotransferase, and urea levels regardless of the administration mode in broiler chickens, compared to the negative control. When administered through both feed and drinking water, garlic significantly increased live weight, weight gain, and lactic acid bacteria count, compared to the negative control. Feeding garlic to broilers had insignificantly affected the digestibility of feed components irrespective of the administration mode. Conclusion: In conclusion, Allium sativum can effectively serve as a feed additive in broiler diets or drinking water, promoting growth performance without harming kidney and liver functions. The present findings help address concerns about antibiotic resistance and residues in poultry products.

Palm kernel meal is a by-product used very sparingly in poultry feed, due to its low nutritional value and gravelly appearance which could be improved by physical or chemical treatments. The aim of this study was to assess the effect of palm-kernel meal fermentation period on its nutritional value and growth performances of broiler chickens. The treatment consisted of fermenting palm kernel meal in a solution of humic acid (HA) or limestone, for 0, 2, 4 and 6 days. A control ration without palm kernel meal (R0) was compared to rations containing 15% unfermented palm kernel cake (R0+) and 15% fermented palm kernel cake in humic acid and limestone solutions. Each experimental ration was randomly assigned to 8 chicks in 4 experimental units of 02 chicks each, repeated 4 times per a 2×3 factorial design (2 fermentation modes and 3 fermentation period). The main results showed that fat content (13.04%) and metabolizable energy (5314 Kcal/kg DM) of palm kernel meal were higher when fermented in humic acid for 6 days. Fermentation in the basic solution for the same period (6 days) increased protein (13.52%) and cellulose (24.21%) contents. Whatever the fermentation mode, the digestive utilization coefficient of dry matter, organic matter, crude protein and crude cellulose increased with the fermentation period. Fermentation mode and period had no significant effect on growth performance. However, growth characteristics tended to improve with fermentation period. In conclusion, fermentation of palm kernel in humic acid and limestone solutions improved significantly (P<0.05) the digestibility of all feed components, enabling chickens to take advantage of the nutrients for better growth performances.

Introduction: The ability of growth-promoting antibiotics to accumulate in livestock products such as meat, eggs, and milk, and the antibiotic resistance conferred on bacteria has prompted researchers to turn to phyto-additives. The present study was designed to evaluate the potential of Typha angustifolia rhizome powder as an alternative to antibiotic growth promoters in broiler chicken. Materials and methods: For this purpose, 512 one-day-old chickens of the Cobb500 strain were randomly distributed in a completely randomized design of 8 treatments of 16 chicks replicated four times. Experimental rations consisted of incorporating into a control ration 1 g of Doxycycline® (0+), and 1, 2, 4, 6, 8, and 10 g of Typha angustifolia /kg of feed, respectively. Results: The main results revealed that feed intake was not significantly affected by the different treatments. Over the study period, supplementing chicken with 6 g of T. angustifolia/kg increased live weight and weight gain by about 6.72% and 6.82%, respectively, compared to the negative control. Similarly, this phyto-additive, at the incorporation rate of 6 g/kg, decreased the chicken feed conversion ratio by 12.83% compared to the control without additives. The 6 g of Typha angustifolia/kg of feed induced a significant increase in the weight, length, and density of the intestine as compared to the negative control ration. This phyto-additive, whatever the rate, significantly increased the number of lactic acid bacteria, and the digestibility of crude protein and dietary fiber compared to the negative control. Apart from the serum concentration of total cholesterol and high-density cholesterol, which increased significantly with 1 g of Typha angustifolia compared to the negative control, all the haemato-biochemical parameters were not significantly affected by this phyto-additive, whatever the incorporation rate. Conclusion: In the condition of the present study, it was concluded that 6 g of Typha angustifolia/kg of feed can be used as a substitute for antibiotics growth promoters in animal feed.

The rhizomes of Cyperus (C.) alternifolius, Echinochloa (E.) pyramidalis, Typha (T.) angustifolia, and Imperata (I.) cylindrica are rich in secondary metabolites and have diverse pharmacological activities. The present study was designed to evaluate the effects of dietary C. alternifolius, E. pyramidalis, T. angustifolia, and I. cylindrical rhizomes on the performance of broiler chickens. A total of 384 day-old chicks were randomly assigned to six treatment groups (each treatment replicated four times). The first group received a basal diet (negative control), and the second group received a basal diet with 1 gr of antibiotic (Doxicycline, positive control). Other groups received a basal diet with 2 gr of each phyto-additives/kg feed. The results revealed that treatments had no significant effects on feed intake and carcass yield in chickens. The C. alternifolius and T. angustifolia significantly increased live weight and weight gain, and decreased feed conversion ratio, compared to negative control. The addition of C. alternifolius, T. angustifolia, and I. cylindrica to broilers’ diet significantly increased the apparent digestibility of dry matter and crude protein, compared to the negative control. Compared to the negative control, the lactic acid bacteria count significantly increased with the incorporation of T. angustifolia and I. cylindrica. The granulocytes count and globulins concentration were not affected by the different treatments. However, the lymphocyte count was significantly decreased with the diet containing E. pyramidalis compared to the negative and positive controls, and the diets containing C. alternifolius and T. angustifolia. The spleen and bursa weights and volumes significantly increased in all groups of chickens fed on phyto-additives, compared to the negative control. Except for haematocrit, which significantly increased with C. alternifolius and T. angustifolia in the treatments compared to the negative control, the feed additives did not significantly affect the hematological parameters. Compared to the negative control, T. angustifolia and I. cylindrica significantly increased HDL-cholesterol concentration in broiler chickens’ serum, while all treatment groups were comparable for all the other biochemical parameters. Incorporating 2 g of C. alternifolius and T. angustifolia in broiler chickens’ feed improves feed digestibility, enhances the population of lactic acid bacteria in the gut, and causes subsequent improvement in growth performance.

This study aimed to investigate the effect of ginger (Zingiber officinale, Rosc.) essential oil on growth and laying performances, egg yolk antioxidant and cholesterol status, and serum metabolites in Japanese quail. Eighty 3-week-old Japanese quails weighing between 120 and 130 g were equally and randomly assigned to four groups receiving daily and orally, respectively, 100µl/kg body weight (bw) distilled water and 50, 100, and 150µl/kg bw of ginger rhizomes essential oil, respectively. The entire feeding trial for all groups lasted for 9 weeks and theZ. officinaleessential oil effects were studied on growth and laying performances, serum metabolites, and egg yolk antioxidant and cholesterol status. Results revealed that feed intake, live and body weights gain, feed conversion ratio, egg production, and weekly mass of eggs were not significantly (P>0.05) influenced by oral administration of ginger rhizomes essential oil. Unlike the abdominal fat weight which decreased significantly (p 0.05) on liver, intestine, heart, and gizzard relative weights as compared to the control. Egg weight markedly (Pµl/kg bw of ginger rhizomes essential oil compared to control group. In conclusion, oral administration of 100 to 150µl/kg bw of ginger rhizomes essential oil to laying Japanese quails positively influences egg weight and decreased serum and egg cholesterols without any adverse effect on feed intake and body weight gain.

Because of speculated risk in generating antibiotic resistance in pathogenic microbiota, natural products from plant origin due to their diverse biological activities, have recently gained a great attention in animal nutrition. This study was designed to evaluate graded levels of neem seed oil on growth performance of broiler chickens. A total of 400‐day‐old chicks were randomly allocated to five experimental treatment groups. Experimental rations consisted of supplementing basal diet (R0⁻) with 1 g antibiotic (R0 + ), 15, 20 and 25 g neem seed oil/kg of feed. Data were recorded on feed intake, weight gain, feed conversion ratio, and serum biochemical parameters. Result revealed that feeding broiler chicks with 25 g of neem oil/kg of feed resulted in a marked (P < 0.05) decreased in feed intake as compared to the other treatments in the starter phase. The average live body weight and the weight gain decreased with increasing level of neem oil in the ration. Supplementation of poultry feed with graded levels of neem oil has no marked (P > 0.05) effect on carcass yield and relative weight of organs except for liver weight which significantly (P < 0.05) increased with the highest dose of neem oil. Serum content in total proteins, total cholesterol, HDL‐cholesterol, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatinine were not significantly (P > 0.05) affected by the graded levels of neem oil. LDL‐cholesterol significantly (P < 0.05) decreased with diets supplemented 20 g of neem oil/kg while triglycerides significantly increased with the highest doses of oil (20 and 25 g/kg) as compared to the negative and positive control rations. In conclusion, feeding broilers with Azadirachta indica seed oil has no beneficial effect on growth performance but may lead to the production of low‐cholesterol chicken meat as demand by health‐conscious consumers.

Cette étude avait pour objectif de déterminer les besoins en lysine et en méthionine de la poule barrée du Cameroun. En démarrage (1 à 12 semaines), les rations expérimentales contenaient 1,2% de lysine et 0,6% de méthionine (DL_1,2M_0,6), 1,2% de lysine et 0,4% de méthionine (DL_1,2M_0,4), 0,8% de lysine et 0,6% de méthionine (DL_0,8M_0,6) et 0,8% de lysine et 0,4% de méthionine (DL_0,8M_0,4). En phase croissance (13 à 20 semaines), les rations contenaient 0,8% de lysine et 0,3% de méthionine (FL_0,8M_0,3), 0,8% de lysine et 0,5% de méthionine (FL_0,8M_0,5), 0,7% de lysine et 0,3% de méthionine (FL_0,7M_0,3) et 0,7% de lysine et 0,5% de méthionine (FL_0,7M_0,5). En phase démarrage, les résultats ont révélé que l’indice de consommation (IC) est plus faible (PDL_1,2M_0,4 qui a été par ailleurs la ration la moins consommée. Les taux de la lysine et de la méthionine mis en évidence en phase de démarrage n’ont eu aucun effet significatif (PFL_0,7M_0,5) chez la poule alors que chez le coq, c’est avec le même taux de lysine (0,7%) et le taux de méthionine le plus faible (FL_0,7M_0,3) que le poids vif le plus élevé a été enregistré. En conclusion, en phase démarrage, 1,2% de lysine et 0,4% de méthionine sont nécessaires pour un meilleur IC alors qu’en phase croissance, 0,3 et 0,5% de méthionine permettent respectivement avec un taux constant de lysine (0,7%) d’obtenir les meilleurs taux de croissance chez le coq et la poule Barrée camerounaise. Mots clés: Acide aminé, lysine, méthionine, performance de croissance, poule villageoise.