Effect of palm kernel meal (Elaeis guineensis, Jacq, 1763) in the diet on digestive transit and some serum parameters in Nile tilapia (Oreochromis niloticus, Linnaeus, 1758)

As part of the continuation of the thesis work on the valuation of palm kernel cake in the diet of Nile tilapia, a study was carried out from March 7th to April 12th, 2018 at the Aquaculture Research and Development Unit of the University of Lome in Togo. It aims to  evaluate the digestive use efficiency of palm kernel cake (PK) in Oreochromis niloticus. So, two lots of 180 male Oreochromis niloticus; juvenile of 57.14 ± 4.43 g and adults of 144.04 ± 7.65 g were each randomly distributed in 9 recirculate system concrete tanks of 600 L, at 20 fish per tank, filled to 250 liters of water. They were fed two weeks with three isoprotein diets (32% crude protein) in triplicate, distributed manually three times a day at 2% of the fish biomass; standard fish feed Raanan (RA) and two diets containing 30% PK untreated (R3) or cooked in water for one hour (R3C). After a 2 days fasting, some fish were fed once again to satiety (8am). Then a sample of 6 fish per lot was euthanized in a clove solution. After blood sampling, the fish were dissected at 0h, 1h, 4h, 8h, 12h and 24h after feeding to measure blood and intestinal parameters. The results obtained show that raw PK is an unpalatable fibrous ingredient but well valued once cooked with a digestive improvement allowing good absorption of food micronutrients in both juveniles and adults. This absorption led to changing in the serum protein level for growth of fish and nitrogenous excretion in the form of urea. The cooking slowed the transit of the food into the digestive tract of tilapia, this can improve zootechnical performance of fish

Current situation of fish farming in Togo

In Togo, fish farming is faced with several problems which oblige farmers to develop local production techniques that explain the low level of production. To assess the current situation, a survey was conducted to collect information on this activity in 91 Togolese fish farms located in the five regions of the country. The survey has shown the existence of two production systems, namely the extensive majority system (87.91%) practiced in ponds and water reservoirs and the semi intensive system (12.09%) implemented in tanks and ponds. The lack of accurate data has made it difficult to estimate production. Nevertheless, eight fish species are found in these environments in which tilapia (Oreochromis niloticus) and the African cat fish (Clarias gariepinus) represent 80% of farmed species. Feed, representing over 50% of fish production cost, remains the major constraint on the development of this activity. However, agro-industrial by-product resources were available depending on region and are recoverable for use as fish feed. This is the case for palm kernel meal which was abundant and little studied in Togo. Sociologically, fish farming was more a matter of group (61.54%) than individual (38.46%) activity. The extensive fish farming system deserves to be improved and agro-industrial by-products analyzed and valued for the promotion of fish farming in Togo.Keywords: Fish, food, fish farming infrastructure, agro-industrial by-products, palm kernel meal

Genetic diversity of indigenous guinea fowl (Numida meleagris) using microsatellite markers in northern Togo

The present study was financially supported by the German Academic Exchange Service Deutscher Akademischer Austauschdienst (DAAD) through the In-Country/In-Region scholarship program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Indigenous guinea fowl is an important animal resource for improving rural household income. In order to provide molecular data for a sustainable management of this poultry resource, an assessment of the genetic diversity and phylogenic relationships was undertaken on seven guinea fowl phenotypes from two agroecological zones (Dry Savannah and Atakora) of Togo. Genotyping was carried out using 18 microsatellite markers on 94 individuals from Dry Savannah (59) and Atakora (35) zones. The results obtained showed a high genetic diversity, with six as an average alleles per locus and an observed heterozygosity of 0.512. However, the FIS values varied from 0.047 (Lavender) to 0.257 (Albino), reflecting a deficit of heterozygotes, which suggests low to moderate inbreeding levels. The genetic distances between phenotypes are low, ranging from 0.0068 (Bonaparte-Pearl grey) to 0.1559 (Lavender-Albino), unlike the strong genetic identities that reflect a strong genetic similarity between the seven phenotypes of indigenous guinea fowl studied. These results indicate the existence of a single indigenous guinea fowl population, derived from three probable parental populations, with a high within population genetic diversity (phenotypic or agroecological zone). These results could be of use to conservation and improvement programs aiming at the maintenance and sustainable exploitation of this important socio-cultural and economic resource in Togo.Deutscher Akademischer Austausch Dienst (DAAD

Alleviating heat stress effects in poultry: updates on methods and mechanisms of actions

Heat stress is a threat that can lead to significant financial losses in the production of poultry in the world’s tropical and arid regions. The degree of heat stress (mild, moderate, severe) experienced by poultry depends mainly on thermal radiation, humidity, the animal’s thermoregulatory ability, metabolic rate, age, intensity, and duration of the heat stress. Contemporary commercial broiler chickens have a rapid metabolism, which makes them produce higher heat and be prone to heat stress. The negative effect of heat stress on poultry birds’ physiology, health, production, welfare, and behaviors are reviewed in detail in this work. The appropriate mitigation strategies for heat stress in poultry are equally explored in this review. Interestingly, each of these strategies finds its applicability at different stages of a poultry’s lifecycle. For instance, gene mapping prior to breeding and genetic selection during breeding are promising tools for developing heat-resistant breeds. Thermal conditioning during embryonic development or early life enhances the ability of birds to tolerate heat during their adult life. Nutritional management such as dietary manipulations, nighttime feeding, and wet feeding often, applied with timely and effective correction of environmental conditions have been proven to ameliorate the effect of heat stress in chicks and adult birds. As long as the climatic crises persist, heat stress may continue to require considerable attention; thus, it is imperative to explore the current happenings and pay attention to the future trajectory of heat stress effects on poultry production

Exploitation Patterns of Anchovies (Engraulis encrasicolus) by Marine Artisanal Fisheries in Togo (West Africa)

Pelagic fish, including sardines and anchovies (Order Clupeiformes), are the most common species taken by artisanal marine fisheries along the Togolese coast. We investigated fisher involvement as well as fish captures over a period of 10 years, particularly of the European anchovy (Engraulis encrasicolus). Our results indicate that 60% of fishers operated from the Lomé fishing harbour, most fishers being Ghanaians working seasonally in Togo. 63.7% of all the fishers used canoes with outboards, a higher percentage compared to the previous decades. Seven fishing gear type were identified, with bottom gillnet and surface gillnet being the most commonly used. However, in the most important fishing camp in the country in terms of fish production (Lomé fishing harbour), all fishers used shark nets. Overall, fisheries catches did not change significantly across years, but anchovy fishing effort and catch per unit of effort (CPUE) declined over the study period, suggesting some depletion of the species stocks on the Togolese coast and a demotivation of fishers.

Stratégies alimentaires des poulets de chair basées sur des compléments mis au point au Bénin

L’objectif de cette étude a été d’évaluer l’effet de la forme de présentation et du mode de distribution des aliments sur les performances des poulets de chair nourris à base de compléments mis point au Bénin. L’essai a porté sur 400 poussins Ross, répartis en 5 traitements alimentaires de 4 répétitions de 20 poussins élevés sur litière pendant 7 semaines. Les traitements étaient basés sur deux aliments présentés sous forme farineuse et granulée. Il s’agit d’un aliment complet et d’un complément alimentaire protéique au maïs grain. Les traitements ont été respectivement, les aliments complets farineux et granulé (ACF et ACG) qui ont été les témoins et servi en continu; le complément farineux et le complément granulé servi en séquentiel (CFm et CGm) et le complément granulé mélangé au maïs servi en continu (CGM). Les résultats ont montré que le complément granulé permet une meilleure croissance pondérale alors que le complément farineux donne une meilleure rentabilité en mode séquentiel. Mots clés: Compléments alimentaires, mode de distribution, Forme de présentation, poulets de chair, Béni

Stratégies alimentaires des poulets de chair basées sur des compléments mis au point au Bénin

The objective of this study was to evaluate the effect of feed form and delivery mode on the performance of broilers fed supplements developed in Benin. The trial involved 400 Ross chicks, divided into 5 feed treatments of 4 replicates of 20 chicks raised on litter for 7 weeks. The treatments were based on two feeds presented in mash and pellet form. These were a balanced feed and a protein feed supplemented with corn grain. The treatments were respectively, the balanced mashed and pelleted feed (ACF and ACG) which were the control and fed continuously; the mashed and pelleted supplement fed sequentially (CFm and CGm) and the pelleted protein supplement mixed with corn fed continuously (CGM). The results showed that the pelleted protein supplement provided better weight growth while the mashed supplement provided better profitability in sequential mode. Keywords: Feed complements, distribution mode, presentation form, broilers, BeninL’objectif de cette étude a été d’évaluer l’effet de la forme de présentation et du mode de distribution des aliments sur les performances des poulets de chair nourris à base de compléments mis point au Bénin. L’essai a porté sur 400 poussins Ross, répartis en 5 traitements alimentaires de 4 répétitions de 20 poussins élevés sur litière pendant 7 semaines. Les traitements étaient basés sur deux aliments présentés sous forme farineuse et granulée. Il s’agit d’un aliment complet et d’un complément alimentaire protéique au maïs grain. Les traitements ont été respectivement, les aliments complets farineux et granulé (ACF et ACG) qui ont été les témoins et servi en continu; le complément farineux et le complément granulé servi en séquentiel (CFm et CGm) et le complément granulé mélangé au maïs servi en continu (CGM). Les résultats ont montré que le complément granulé permet une meilleure croissance pondérale alors que le complément farineux donne une meilleure rentabilité en mode séquentiel. Mots clés: Compléments alimentaires, mode de distribution, Forme de présentation, poulets de chair, Béni

Effet de la densite de charge sur les performances zootechniques du tilapia Oreochromis niloticus (linne, 1758) eleve en bacs en Beton: Effect of stocking density on zootechnical performance of tilapia Oreochromis niloticus (linne, 1758) reared in concrete tanks

Afin d’évaluer l’effet de la densité de charge sur les performances zootechniques des juvéniles du tilapia (Oreochromis niloticus) en bacs, une étude de 168 jours a été réalisée à l’unité de Recherche et de Développement en Aquaculture, sise à l’Université de Lomé, de janvier à juillet 2018. L'expérimentation a été menée sur 450 juvéniles monosexes mâles du tilapia d’un poids moyen de 16 ± 0,33g. Ces juvéniles ont été répartis en triplicat dans 09 bacs en béton de 600 litres d’eau de capacité chacun. Trois différentes densités ont été utilisées notamment, D1 (50 individus dans 125 L), D2 (50 individus dans 250 L) et D3 (50 individus dans 500 L). Les poissons étaient nourris manuellement trois fois par jour avec un aliment standard, Raanan à 32% de protéines brutes. A la fin de l’étude, les poids moyens finaux ont varié entre 169,7 ±2,5 g et 253,7± 5,0 g. Le taux de survie a varié de 96,0 ± 2,0% à 97,3 ± 1,2%. Le taux de croissance journalier (TCJ) était de 0,9 ± 0,02 g/j pour D1 ; 1,4 ± 0,03 g/j pour D2 et D3 a donné 1,2 ± 1,2 g/j. Le taux de conversion alimentaire (TCA) a varié de 1,4 ± 0,43 à 1,8 ± 0,08 en fonction des différents traitements. Il ressort de cette étude que la densité D2 a présenté les meilleures performances zootechniques. In order to assess the effect of stocking density on the zootechnical performance of juvenile tilapia (Oreochromis niloticus) in tanks, a 168-day study was carried out at the Aquaculture Research and Development unit, inside the University of Lome, from January to July 2018. The experiment was carried out on 450 monosex male tilapia juveniles with an average weight of 16 ± 0.33g. These fishes were distributed in triplicate in 09 concrete tanks with a capacity of 600 liters each. Three different densities were used, D1 (50 fishes in 125 L), D2 (50 fishes in 250 L) and D3 (50 individuals in 500L). The fish were fed manually three times a day with a standard feed, Raanan at 32% crude protein. At the end of the study, the final mean weights varied between 169.7 ± 2.5 g and 253.7 ± 5.0 g. The survival rate ranged from 96.0 ± 2.0% to 97.3 ± 1.2%. The daily growth rate (DGR) was 0.9 ± 0.02 g / d for D1; 1.4 ± 0.03 g / d for D2 and 1.2 ± 1.2 g / d for D3. The feed conversion ratio (FCR) varied from 1.4 ± 0.43 to 1.8 ± 0.08 depending on the different treatments. The production parameters were improved with the density D2 which seems to be the interest density for O. niloticus on growing

How can incubation conditions improve the resilience of chicken production in Africa and Europe in the context of global warming?

International audienceGlobal warming affects livestock and especially poultry production, due to a higher variability of environmental conditions and average global temperatures, heat waves, risks for feed supply chains and sanitary issues. Considering chicken meat production that is still growing worldwide, high environmental temperatures decrease poultry growth performance and can even induce mortality. In this context innovative incubation programs were experimentally explored in order to improve the thermotolerance of broilers in the long term. They were aimed at re-introducing thermal variability during the embryogenesis of the bird, when its thermoregulatory system is still immature and plastic, in order to facilitate the later thermotolerance capacities of the bird. Cyclical increases in incubation temperatures, tested with different programs on slow growing birds in Africa, or fast-growing birds in Europe and Israel, have proved their efficacy to decrease mortality at slaughter age with very limited or no effects on performance. The biological basis of these improvements lies in long term physiological, metabolic and epigenetic changes in peripheral and/or central tissues controlling heat production, heat loss and stress response. Research in quails used as a model animal also showed that effects induced by changes in temperature during early incubation could be transferred to next generations with a partial reversibility of effects when the incubation treatment is not applied any more. The application of lower incubation temperatures during the late embryogenesis was also tested in fast growing broilers in order to improve cold tolerance, especially in chick when energy use and costs at start are high. This research could lead to applications in hatcheries for improving the adaptation of chickens in the long term to the foreseen increasingly varying environmental conditions

Influence of zinc sulfate and threonine supplementation on mucin 5ac gene expression in the small intestine and intestinal mucosal morphology in broiler chickens

ABSTRACTA 42-day feeding trial was carried out to evaluate the effect of dietary supplementation of zinc and threonine on the integrity of intestinal mucosa and expression of intestinal mucin 5ac (MUC5AC) gene in broiler chickens. A total of 640-day-old Arbor Acres broiler chicks were allocated to four dietary treatments with eight replicates of 20 birds in a completely randomized design. The experimental diets included T0: control (standard diet), T1: standard diet + 40 mg/kg Zinc Sulfate (ZnSO4), T2: standard diet + 2% L-Threonine (L-Thr) and T3: standard diet + (40 mg/kg ZnSO4 + 0.2% L-Threonine (L-Thr)). During the starter phase, the average daily gain and body weight of birds fed the T1 diet was lower (p < 0.05) than T2 and T0. The villus height (VH) of the jejunum in T2 was longer (p < 0.05) than in T0 and T3. In the ileum, VH for T1 was longer (p < 0.05) than for T0. The MUC5AC mRNA expression in the duodenum at the starter phase was lower (p < 0.05) in T3 than in T2 while in the jejunum, T1 was higher (p < 0.05) than the other treatment groups. The supplementation of zinc and threonine in the diet can improve the intestinal integrity of broiler chickens