Alexis Teguia

Assessment of Aflatoxin Contamination of Maize, Peanut Meal and Poultry Feed Mixtures from Different Agroecological Zones in Cameroon

Mycotoxins affect poultry production by being present in the feed and directly causing a negative impact on bird performance. Carry-over rates of mycotoxins in animal products are, in general, small (except for aflatoxins in milk and eggs) therefore representing a small source of mycotoxins for humans. Mycotoxins present directly in human food represent a much higher risk. The contamination of poultry feed by aflatoxins was determined as a first assessment of this risk in Cameroon. A total of 201 samples of maize, peanut meal, broiler and layer feeds were collected directly at poultry farms, poultry production sites and poultry feed dealers in three agroecological zones (AEZs) of Cameroon and analyzed for moisture content and aflatoxin levels. The results indicate that the mean of the moisture content of maize (14.1%) was significantly (P < 0.05) higher than all other commodities (10.0%–12.7%). Approximately 9% of maize samples were positive for aflatoxin, with concentrations overall ranging from <2 to 42 µg/kg. Most of the samples of peanut meal (100%), broiler (93.3%) and layer feeds (83.0%) were positive with concentrations of positive samples ranging from 39 to 950 µg/kg for peanut meal, 2 to 52 µg/kg for broiler feed and 2 to 23 µg/kg for layer feed. The aflatoxin content of layer feed did not vary by AEZ, while the highest (16.8 µg/kg) and the lowest (8.2 µg/kg) aflatoxin content of broiler feed were respectively recorded in Western High Plateau and in Rainforest agroecological zones. These results suggest that peanut meal is likely to be a high risk feed, and further investigation is needed to guide promotion of safe feeds for poultry in Cameroon.

Guinea-pig productivity under traditional management.

Results of a 12 month study of traditional guinea-pig production in the western highlands of Cameroon are reported. The mean age of guinea-pigs (Cavia porcellus L.) at first parturition, kidding interval and litter size at birth were 126.30±10.40 d, 64.8±1.70 d and 1.63±0.26 kids respectively. The annual reproductive rate was 9.18 kids/breeding doe while the doe post-partum weight was 530 g. Mean body weights at birth, presumed weaning (21 d) and 15 weeks of age were 78.36±3.20, 147.51±8.10 and 418.88±32 g respectively. Type of birth and sex had a significant effect on body weight at all ages. Birth weight dropped significantly from 83.88±2.87 g for singles to 81.57±3.40 g for twins, 74.25±2.39 g for triplets and 73.75±4.12 g for quadruplets. These differences were maintained to maturity (15 weeks). Males were generally heavier than females. Mortality rates were relatively high among kids: 24% at birth, 39% at 3 weeks and 40% at 15 weeks. Productivity indices were 0.827 kg of young weaned per doe per year, 1560 g of young weaned per kg of doe per year and 2.52 kg of young weaned per kg metabolic weight (kg0.75) of female per year.

Growth performance and carcass characteristics of broiler chickens fed diets supplemented with graded levels of charcoal from maize cob or seed of Canarium schweinfurthii Engl

Growth performances and carcass characteristics of broiler chickens fed diets supplemented with graded levels of Canarium schweinfurthii Engl seed (charcoal A) or maize cob (charcoal B) were studied using a total of 110 3-week-old male chicks. 11 experimental diets including a control and other containing either 0.2, 0.4, 0.6, 0.8 or 1% charcoal from C. schweinfurthii Engl seed (A0.2, A0.4, A0.6, A0.8, and A1%, respectively) or from maize cob (B0.2, B0.4, B0.6, B0.8, and B1%, respectively) supplements were used. Each of the diets was fed to ten individually birds caged in a completely randomized design. Results indicated that birds fed 0.2, 0.4, and 0.6% of either charcoal A or B had significantly (P < 0.05) higher final body weights as compared to control birds, while, above 0.6% slightly depressed average final body weights and weight gain. The best growth performance was achieved with 0.2% inclusion of charcoals. There was no significant (P > 0.05) influence of charcoal B on the overall feed intake. Only the B0.6 feed significantly (P < 0.05) improved feed conversion ratio as compared with the control. Dressing percentage, liver weight and abdominal fat were not significantly (P > 0.05) affected by charcoal. However, there was a significant (P < 0.05) reduction in gizzard weight with charcoal B. Charcoal had no significant (P > 0.05) influence on intestine length and weight. More than 0.6% of charcoal A significantly (P < 0.05) depressed intestine density. It was concluded that under the conditions of this study, charcoal from maize cob or Canarium seeds could be used to improve growth performances and some carcass traits in broiler chickens.

Effect of dietary plant charcoal from Canarium schweinfurthii Engl. and maize cob on aflatoxin B1 toxicosis in broiler chickens

residual oil. These disposable clays are the byproduct that could be considered for animals feeding purposes. As mentioned previously, the limiting factor for their use, is mostly the high Al content. Therefore restricted consumption by animal species should be estimated, to avoid bioaccumulation. If Al accounts for 5.3% in wasted clays as an average, maximum intake of clays depending on animal tolerance is (g anim d): 151 in bovines, 19 in sheep, 7 in swine, 0.38 in poultry, 15.1 in horses and 2.3 in rabbits.

Estimation of live body weight in West African dwarf goats from heart girth measurement.

Animal live body weight is an important feature, but can seldom be measured in rural areas due to a lack of reasonably accurate scales. The chief method of weighing animals without scales is to regress body weight on a certain number of body characteristics which can be measured readily (Bhadula et aL, 1979; Poivey, et aL, 1980; Worman et aL, 1980; Buldgen et al., 1984). Such procedures are almost non-existent, however, for the West African Dwarf (WAD) goat. Also, the accuracy of the existing prediction equations has not been reliably ascertained. The objectives of this study were to derive a prediction equation using heart girth circumference as sole regressor and to assess its accuracy.

Effects of heat stress on some reproductive parameters of male cavie (Cavia porcellus) and mitigation strategies using guava (Psidium guajava) leaves essential oil

Climate changes, particularly the increase of temperature are among the main causes behind the decline of fertility in humans as well as animals. In this study, the effects of heat stress on some reproductive parameters of male cavies and mitigation strategies using guava leaves essential oil (GLEO) were studied. For this purpose, 40 male cavies aged 2.5-3 months and weighing between 348 and 446g were divided into 4 groups of 10 animals each and subjected to the following temperatures: Ambient temperature (20-25°C) for the control group, 35°C for group 1, 45°C for group 2 and 45°C+100µl GLEO/kg body weight, administered by gavage to animals for group 3. Exposure time of heat was 7h per day for 60 days. Results reveal that the relative weights of testes, epididymis, vas deferens and seminal vesicles were hardly affected by the temperature levels considered (P>0.05). The mass and individual sperm motility was significantly lower (P<0.05) in cavies exposed to the temperature of 35 and 45°C as compared with those which received GLEO and controls. The percentages of abnormal sperm and altered sperm DNA were higher in animals exposed to temperature of 35 and 45°C as compared with the controls. The activity of superoxide dismutase significantly increased (P<0.05) in animals exposed to temperature of 45°C and in those of 45°C and orally treated with GLEO, compared with cavies exposed to temperature of 45°C without receiving GLEO. The level of malondialdehyde was significantly increased (P<0.05) in animals exposed to temperature of 35 and 45°C, whereas the level of nitric oxide was significantly lower (P<0.05) in exposed animals as compared with controls. It was concluded that the exposure of male cavies at 35 and 45°C for 60 days induce heat stress that causes deterioration of sperm characteristics. These effects that can be mitigated by the administration of guava leaves essential oil.

Assessment of biosecurity level in small-scale broiler farms in the Western highlands of Cameroon (Central Africa)

The recent outbreak of avian influenza in the poultry sector of Cameroon has raised a concern about the level of implementation of biosecurity measures (BM) on poultry farms. Therefore, a study using a questionnaire on 102 randomly selected poultry farms was undertaken. Some measures with high adoption levels (> 90%) included “protection of airing openings of poultry barns by a wire mesh,” “no external animal allowed to enter the farm,” “respect of all-in all-out principle,” “functional footbath,” “rodent control,” and “feedstuff protection from access to rodents.” The least implemented measures (less than 20%) were “wearing of dedicated clothing (clean coveralls and boots) by workers,” “disinfection of visitors,” and “presence of storage room for dead animals.” Only for “isolation” component of biosecurity, compliance with biosecurity measures was good, with more than 50% of farms having an adoption rate greater than 75%. The mean biosecurity score for the assessed farms was 19.29 ± 1.89 for a maximum score of 38 points. The score was significantly and positively correlated (p < 0.05) with the number of chicken and the geographic location of farms. The other results showed that the mean number of broiler per cycle was 550.82 ± 76 for a stocking density of 27.20 ± 6.64 birds per m2. In conclusion, broiler production in the Western highland is dominated by small-scale units with low level of biosecurity practices positively and significantly (p < 0.05) influenced by some production characteristics. To improve biosecurity practices in the area, efforts must focus on measures concerning “sanitation” and “traffic control” components of biosecurity.

Effects of ethanol extract of Bersama engleriana leaves on oxidative stress and reproductive parameters in male Guinea pig ( Cavia porcellus ) exposed to cypermethrin

Pesticides are used to improve agricultural yields; meanwhile they have detrimental effects on human and animal reproduction. This study aimed at evaluating the protective effects of ethanol extract of Bersama engleriana leaves against cypermethrin-induced oxidative stress and reproductive toxicity. Fifty male guinea pigs were divided into 5 groups (G1, G2, G3, G4 and G5) of 10 animals each. During 90 days, animals of G1 were given distilled water orally, while other groups received 137.50 mg/kg body weight (bw) of cypermethrin. In addition, G3, G4 and G5 received respectively 50, 100 and 200 mg/kg bw of ethanol extract of Bersama engleriana leaves. The testicular concentration of malondialdehyde, the activities of superoxide dismutase and catalase decreased significantly (P<0.05) in guinea pigs exposed to cypermethrin and ethanol extract of B. engleriana leaves compared with those exposed to cypermethrin only (G2), while the reverse effect was observed concerning the activity of peroxidases. The time of reaction of male guinea pig in the presence of females and the percentage of abnormal spermatozoa decreased significantly (P<0.05) in animals treated with the insecticide and the ethanol extract of B. engleriana leaves with respect to G2 animals. The weight of testes, the serum level of testosterone, the sperm count, mobility and the percentage of spermatozoa with normal plasma membrane increased significantly (P<0.05) in guinea pigs treated with ethanol extract of B. engleriana leaves compared with those submitted to cypermethrin only. The histological sections of testes in animals exposed to cypermethrin and ethanol extract of B. engleriana leaves showed a normal structure compared with those exposed to cypermethrin only, of which sections of testes revealed the presence of immature germinal cells in the seminiferous tubules lumen. Hence, ethanol extract of B. engleriana leaves prevent the induction of oxidative stress and reproductive parameters impairment by cypermethrin in male guinea pig.

Effets du taux de la lysine et de la méthionine de la ration sur les performances de croissance de la poule Barrée du Cameroun

Cette etude avait pour objectif de determiner les besoins en lysine et en methionine de la poule barree du Cameroun. En demarrage (1 a 12 semaines), les rations experimentales contenaient 1,2% de lysine et 0,6% de methionine ( DL 1,2 M 0,6 ), 1,2% de lysine et 0,4% de methionine (DL 1,2 M 0,4 ), 0,8% de lysine et 0,6% de methionine ( DL 0,8 M 0,6 ) et 0,8% de lysine et 0,4% de methionine ( D L 0,8 M 0,4 ). En phase croissance (13 a 20 semaines), les rations contenaient 0,8% de lysine et 0,3% de methionine ( FL 0,8 M 0,3 ), 0,8% de lysine et 0,5% de methionine ( FL 0,8 M 0,5 ), 0,7% de lysine et 0,3% de methionine ( FL 0,7 M 0,3 ) et 0,7% de lysine et 0,5% de methionine ( FL 0,7 M 0,5 ). En phase demarrage, les resultats ont revele que l’indice de consommation (IC) est plus faible (P<0,05) avec la ration DL 1,2 M 0,4 qui a ete par ailleurs la ration la moins consommee. Les taux de la lysine et de la methionine mis en evidence en phase de demarrage n’ont eu aucun effet significatif (P<0,05) sur le poids vif et le gain de poids a l’âge de 12 semaines. Par contre, a l’âge de 20 semaines, le poids vif a ete significativement plus eleve avec 0,7% de lysine et 0,5% de methionine ( FL 0,7 M 0,5 ) chez la poule alors que chez le coq, c’est avec le meme taux de lysine (0,7%) et le taux de methionine le plus faible ( FL 0,7 M 0,3 ) que le poids vif le plus eleve a ete enregistre. En conclusion, en phase demarrage, 1,2% de lysine et 0,4% de methionine sont necessaires pour un meilleur IC alors qu’en phase croissance, 0,3 et 0,5% de methionine permettent respectivement avec un taux constant de lysine (0,7%) d’obtenir les meilleurs taux de croissance chez le coq et la poule Barree camerounaise. Mots cles : Acide amine, lysine, methionine, performance de croissance, poule villageoise.

A survey for potentially zoonotic gastrointestinal parasites in domestic cavies in Cameroon (Central Africa)

BackgroundFarm animals are usually suspected to transmit infections to humans. Domestic cavies (Cavia porcellus) are hosts to a variety of pathogens, some of which are zoonotic. Several parasites including the protozoa Giardia spp. and Cryptosporidium spp. may be causative agents of gastrointestinal disorders in domestic cavies and humans. The aim of the study was to investigate the occurrence of potentially zoonotic protozoa as well as any potential zoonotic gastrointestinal parasite in domestic cavies raised under a semi extensive system in the rural areas of Cameroon.ResultsGiardia/Cryptosporidium antigens were detected in 12.90% of cavies. Helminthe eggs were found in 1.52% of animals. The prevalence of Paraspidodera uncinata, Heligmosomoides polygyrus (also known as Nematospiroides dubius) and Trichuris sp. was 1% (4/397), 0.3% (1/397), and 0.3% (1/397), respectively. Presence of Giardia/Cryptosporidium was unrelated to the occurrence of diarrhea, as none of the positive samples was from a diarrheic individual.ConclusionDomestic cavies are hosts of Giardia/Cryptosporidium and appear as potential source of human giardiasis, cryptosporidiosis and infection with H. polygyrus in Cameroon. In keeping with the One Health Initiative, veterinarians and medical doctors should collaborate to address the problem of Giardia and Cryptosporidium infection in cavies and cavy breeders both in Cameroon and other countries with a similar cavy breeding system. Follow-up studies are required to further taxonomically characterize these cavy parasites and to determine their routes of transmission to humans.