Tuberculosis in dromedary camels slaughtered in Nigeria: a documentation of lesions at postmortem

Tropical Animal Health and Production - In comparison with other livestock, tuberculosis (TB) in camels has not been extensively studied in Nigeria. Camels in the hands of Nigerian pastoralists...     

Multivariate analysis of sexual size dimorphism in local turkeys (Meleagris gallopavo) in Nigeria

Sexual size dimorphism is a key evolutionary feature that can lead to important biological insights. To improve methods of sexing live birds in the field, we assessed sexual size dimorphism in Nigerian local turkeys (Meleagris gallopavo) using multivariate techniques. Measurements were taken on 125 twenty-week-old birds reared under the intensive management system. The body parameters measured were body weight, body length, breast girth, thigh length, shank length, keel length, wing length and wing span. Univariate analysis revealed that toms (males) had significantly (P < 0.05) higher mean values than hens (females) in all the measured traits. Positive phenotypic correlations between body weight and body measurements ranged from 0.445 to 0.821 in toms and 0.053–0.660 in hens, respectively. Three principal components (PC1, PC2 and PC3) were extracted in toms, each accounting for 63.70%, 19.42% and 5.72% of the total variance, respectively. However, four principal components (PC1, PC2, PC3 and PC4) were extracted in hens, which explained 54.03%, 15.29%, 11.68% and 6.95%, respectively of the generalised variance. A stepwise discriminant function analysis of the eight morphological traits indicated that body weight, body length, tail length and wing span were the most discriminating variables in separating the sexes. The single discriminant function obtained was able to correctly classify 100% of the birds into their source population. The results obtained from the present study could aid future management decisions, ecological studies and conservation of local turkeys in a developing economy.     

Multivariate characterisation of the phenotypic traits of Djallonke and Sahel sheep in Northern Ghana

The characterisation of the small ruminant populations in developing countries will play a major role in the maintenance of the genetic resources as the basis for future improvement in livestock production. The present study aimed at morphological characterisation of the two main breeds of sheep in Ghana by assessing variation within and between breed populations using principal component and discriminant analyses. The two breeds were the Sahel and the Djallonke sheep of both sexes and of two groups namely, young (1 year old, consisting of 74 animals) and mature sheep (≥2 years old, comprising 219 animals). The analysis of variance revealed significant (P?<?0.05) differences in the morphological traits of the Sahel and the Djallonke sheep breeds with higher values recorded for the former. Sexual dimorphism was in favour of male animals in all the morphological traits examined. Mature animals also had comparative advantage over the young. Two principal components were extracted to discern the structure of the two genetic groups. The most discriminating traits between the two sheep breeds were rump height, height at withers, neck girth and pin-bone width. Mahalanobis distance between the two genetic groups was 5.723 (P?<?0.0001). The developed discriminant functions clearly discriminated and classified the Sahel and the Djallonke sheep into their breeds of origin, thus yielding 100, 93.4 and 90.4 % accurate classification for the rams, ewes and the overall sheep population, respectively. The present approach would greatly help in establishing management and conservation policies for the sustainable production of the two Ghanaian sheep breeds.     

Physiological and haematological indices suggest superior heat tolerance of white-coloured West African Dwarf sheep in the hot humid tropics

Coat colour contributes to physiological adaptation in mammals and mediates response to thermal stress. Twenty-four adult West African Dwarf sheep of both sexes and with different coat colour types were used in this study. We measured rectal temperature (RT), respiratory rate (RR) and pulse rate (PR) before sunrise and sunset during the late dry season (January–March) and early rainy season (April–June) as well as packed cell volume (PCV), red blood cell (RBC) count, white blood cell (WBC) count, plasma sodium (Na⁺) and potassium (K⁺). Animals with black coat colour had the highest (P?<?0.05) mean values of 38.92?±?0.03 °C, 65.09?±?1.06 breaths/min, 81.35?±?0.78 beats/min, 1.70?±?0.01 for RT, RR, PR and heat stress index (HSI), respectively, followed by brown mouflon and brown with extensive white, while the Badger Face coloured sheep had the least mean values. There were significant (P?<?0.05) differences between male and female sheep for RT, RR, PR and HSI. Season had a significant (P?<?0.05) effect on RT, RR, PR and HSI. Coat colour and sex also significantly (P?<?0.01) affected RBC, WBC, Na⁺ and K⁺. Seasonal variation (P?<?0.05) in all the blood parameters was observed, with the exception of PCV. Interaction effect of coat colour and sex was significant (P?<?0.05) on RT and HSI. Correlation coefficients among the measured traits ranged from positive to negative values. These results indicate that selection of white-coloured sheep to attenuate heat stress is desirable in the hot humid tropics.     

Virulent gene profile and antibiotic susceptibility pattern of Shiga toxin-producing Escherichia coli (STEC) from cattle and camels in Maiduguri,North-Eastern Nigeria

Tropical Animal Health and Production - Prevalence and distribution of Shiga toxin-producing Escherichia coli (STEC) serogroups from the faecal samples of cattle and camels slaughter in Maiduguri...     

<Emphasis Type="Italic">Mycobacterium bovis</Emphasis>, but also <Emphasis Type="Italic">M. africanum</Emphasis> present in raw milk of pastoral cattle in north-central Nigeria

Using deletion typing technique, five mycobacteria isolated from unpasteurised milk samples from cows in north-central Nigeria were characterized as Mycobacterium bovis (n = 4) and M. africanum (n = 1). This report emphasizes that transmission between the animal and human reservoir is a serious threat in Nigeria.     

Investigation of African swine fever in slaughtered pigs,Plateau state,Nigeria, 2004-2006

The occurrence of African swine fever (ASF) DNA in slaughtered pigs in the major pig producing areas of Plateau state over a 2-year period was investigated. Three hundred fifty-nine pig tissue samples from five local government councils (LGCs) were analyzed by clinical signs (C/S), postmortem (PM) lesions and polymerase chain reaction (PCR). The results of diagnosis made by C/S and PM were compared to results obtained by PCR. Out of the 359 abattoir samples, 13 (3.62%) were positive by examination of C/S and PM lesions while 346 (96.38%) were negative. Jos-north LGC had the highest occurrence of PCR positive samples (31 samples); Panyam in Mangu LGC had no positive result. PCR analysis identified 53 positive samples (14.76%); more than 40 were identified on the field. Of the samples, 306 were PCR negative, thus giving a true ASF status of pigs in Plateau state. Analysis of the results, variables involved in the ASF spread and predictable effects of such findings in the pig industry in Plateau state and Nigeria as a whole is discussed.     

Farmers’ choice of genotypes and trait preferences in tropically adapted chickens in five agro-ecological zones in Nigeria

This study aimed at determining chicken genotypes of choice and traits preference in chicken by smallholder farmers in Nigeria. Data were obtained from a total of 2063 farmers using structured questionnaires in five agro-ecological zones in Nigeria. Chi square (χ²) statistics was used to explore relationships between categorical variables. The mean ranks of the six genotypes and twelve traits of preference were compared using the non-parametric Kruskal–Wallis H (with Mann–Whitney U test for post hoc separation of mean ranks), Friedman, and Wilcoxon signed-rank (with Bonferroni’s adjustments) tests. Categorical principal component analysis (CATPCA) was used to assign farmers into groups. Gender distribution of farmers was found to be statistically significant (χ²?=?16.599; P?≤?0.002) across the zones. With the exception of Shika Brown, preferences for chicken genotypes were significantly (P?≤?0.01) influenced by agro-ecological zone. However, gender differentiated response was only significant (P?≤?0.01) in Sasso chicken with more preference by male farmers. Overall, FUNAAB Alpha, Sasso, and Noiler chicken were ranked 1st, followed by Kuroiler (4th), Shika Brown (5th), and Fulani birds (6th), respectively. Within genotypes, within and across zones and gender, preferences for traits varied significantly (P?≤?0.005 and P?≤?0.01). Traits of preference for selection of chicken breeding stock tended towards body size, egg number, egg size, and meat taste. Spearman’s rank order correlation coefficients of traits of preference were significant (P?≤?0.01) and ranged from 0.22 to 0.90. The two PCs extracted, which explained 65.3% of the variability in the dataset, were able to assign the farmers into two groups based on preference for body size of cock and hen and the other ten traits combined. The present findings may guide the choice of appropriate chicken genotypes while the traits of economic importance may be incorporated into future genetic improvement and conservation programs in Nigeria.

     

Comparative multivariate analysis of biometric traits of West African Dwarf and Red Sokoto goats

The population structure of 302 randomly selected West African Dwarf (WAD) and Red Sokoto (RS) goats was examined using multivariate morphometric analyses. This was to make the case for conservation, rational management and genetic improvement of these two most important Nigerian goat breeds. Fifteen morphometric measurements were made on each individual animal. RS goats were superior (P < 0.05) to the WAD for the body size and skeletal proportions investigated. The phenotypic variability between the two breeds was revealed by their mutual responses in the principal components. While four principal components were extracted for WAD goats, three components were obtained for their RS counterparts with variation in the loading traits of each component for each breed. The Mahalanobis distance of 72.28 indicated a high degree of spatial racial separation in morphology between the genotypes. The Ward’s option of the cluster analysis consolidated the morphometric distinctness of the two breeds. Application of selective breeding to genetic improvement would benefit from the detected phenotypic differentiation. Other implications for management and conservation of the goats are highlighted.     

Smallholder cattle farmers’ breeding practices and trait preferences in a tropical Guinea savanna agro-ecological zone

The present study was embarked upon to determine the breeding practices and choice of selection and breeding traits of cattle farmers in Nasarawa State and the Federal Capital Territory (FCT), Abuja, Nigeria. A total of 180 smallholder cattle herders were randomly sampled. However, analysis of data was restricted to 144 herders (81 from FCT and 63 from Nasarawa State). Primary data were collected through individual structured questionnaire administration. Chi-square (χ2) statistics were used to compare categorical variables. Arithmetic means of continuous variables between locations were tested using T test. Rank means were also calculated for within- and between-location comparisons of the preference traits. Chi-square automatic interaction detection (CHAID) algorithm was used to determine the influence of socio-economic parameters on the traits of preference. Access to credit, personal savings, and type of landholding were significantly (P?<?0.05) different between the two locations with higher values recorded for farmers in FCT. However, farmers in Nasarawa State had significantly higher land expanse (2.28?±?0.19 versus 1.29?±?0.09). The production objectives were rated similar between locations. The number of foundation stock differed significantly between farmers in the two locations with higher mean recorded in Nasarawa (7.37?±?0.37) compared to FCT (5.18?±?0.19). However, mean herd size was higher (34.60?±?2.58 versus 27.63?±?2.00; P?<?0.05) in FCT than Nasarawa. Among the productivity indices, only average age at first parturition and average calving interval were significantly (P?<?0.05) influenced by location. Within the FCT, calving interval was the trait of utmost importance in selecting the breeding stock, followed by milk yield, disease resistance, and body size. In Nasarawa State, calving interval, disease resistance, milk yield, body size, and survival were ranked similarly (P??>0.05). Across the two locations, body conformation (P?<?0.05) and calving interval (P?<?0.01) were more highly rated in FCT than Nasarawa State, while heat tolerance was less rated (P?<?0.05) in the former. All the traits of preference were influenced by socio-economic factors, and could be exploited in future breeding plans to boost cattle production. A new livestock census in the study area is also advocated to reflect the current reality as regards cattle distribution.