Sahel Goats Research Articles

WITHDRAWN:Genetic diversity and effect of selection at the mitochondrial hypervariable region in major Nigerian indigenous goat breeds.

Mitochondrial DNA (mtDNA) hypervariable region 1 ( HV1) sequences of three Nigerian indigenous goat breeds; West African Dwarf (WAD), Red Sokoto (RS) and Sahel were used to investigate the genetic diversity and effect of selection between and among these populations. Deoxyribonucleic acid (DNA) of Nigerian indigenous chicken was extracted from blood samples collected and preserved on Fast Technology for Analysis (FTA) paper. The extracted DNA were amplified and sequenced with predefined mitochondria (mtDNA) primer sets for HV1. Eighty-seven (87) polymorphic sites were found in 115 sequences which were grouped into 92 haplotypes. The mean haplotypic and nucleotide diversity were found to be 0.996±0.002 and 0.092±0.04 respectively. Genetic variation within population and between populations accounted for 97.26% and 2.74% of the total maternal variation respectively, with FST value of 0.0274. The Tajima's (D) and Fu's (F) test of neutrality were significant (P<0.05) and negative with the mean value of -1.12 and -21.34 respectively which is an indication of population expansion. The result further revealed that the WAD and RS goats are closely related with less genetic distance value of 0.01, and high genetic distance value (0.02) was observed between RS and Sahel goats and WAD and Sahel goats. Selection analysis result shows that there is more positive selection site (6 sites) to negative site (5 sites) among the Nigerian goats, which signifies how diverse they are as well as how nature has being trying to confer genetic fitness to these breeds.

Phenotypic variations in osmotic lysis of Sahel goat erythrocytes in non-ionic glucose media.

Erythrocyte osmotic lysis in deionised glucose media is regulated by glucose influx, cation efflux, and changes in cell volume after water diffusion. Transmembrane fluxes may be affected by varied expression of glucose transporter protein and susceptibility of membrane proteins to glucose-induced glycosylation and oxidation in various physiologic states. Variations in haemolysis of Sahel goat erythrocytes after incubation in hyposmotic non-ionic glucose media, associated with sex, age, late pregnancy, and lactation, were investigated. The osmotic fragility curve in glucose media was sigmoidal with erythrocytes from goats in late pregnancy (PRE) or lactation (LAC) or from kid (KGT) or middle-aged (MGT) goats. Non-sigmoidal phenotype occurred in yearlings (YGT) and old (OGT) goats. The composite fragility phenotype for males and non-pregnant dry (NPD) females was non-sigmoidal. Erythrocytes with non-sigmoidal curves were more stable than those with sigmoidal curves because of inflectional shift of the curve to the left. Erythrocytes tended to be more fragile with male than female sex, KGT and MGT than YGT and OGT, and LAC and PRE than NPD. Thus, sex, age, pregnancy, and lactation affected the haemolytic pattern of goat erythrocytes in glucose media. The physiologic state of the goat affected the in vitro interaction of glucose with erythrocytes, causing variations in osmotic stability with variants of fragility phenotype. Variations in the effect of high extracellular glucose concentrations on the functions of membrane-associated glucose transporter, aquaporins, and the cation cotransporter were presumed to be relevant in regulating the physical properties of goat erythrocytes under osmotic stress.

The influence of sex on the haematological values of apparently healthy adult Nigerian Sahel goats

Blood samples were collected from fifty apparently healthy adult Sahel goats, twenty five each of male and female in Maiduguri to assess the influence of sex on their haematology. The red blood cell (RBC) counts, white blood cell (WBC) counts, haemoglobin (Hb) concentration, packed cell volume (PCV), platelet counts, neutrophils, eosinophils, lymphocytes, monocytes and basophils counts were determined. The mean corpuscular volume (MCV), the mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were also determined. The RBC, WBC, MCH and neutrophil values were higher (P&lt;0.05) in female than male goats. However, the platelet, MCV, eosinophil and monocyte values were higher (P&lt;0.05) in male than female goats. The PCV, Hb, MCHC, lymphocytes and basophil values were comparable (P&gt;0.05) in both sexes. The variations may be due to breed idiosyncrasies or inherent sex differences among male and female Sahel goats. The haematological values obtained in this study were significant, but did not differ from the normal values for caprine species. In conclusion, sex significantly influenced the RBC, WBC, MCV, MCH, platelet, neutrophil, eosinophil and monocyte values in this study.Keywords: Haemogram, Maiduguri, Nigeria, Sahel Goats, Sex

Phenotypic drift in osmotic fragility of Sahel goat erythrocytes associated with variability of median fragility

A typical mammalian erythrocyte fragility phenotype (EFP) exhibits a sigmoidal curve of the dependence of fragilities (% haemolysis) on hypotonic saline concentrations, but the goat EFP tends to be hyperbolic. Physiological variation in median erythrocyte fragility (MEF) and the associated EFP of Sahel goats was investigated. Erythrocyte osmotic fragility (EOF) was determined in hypotonic saline using heparinized venous blood from 47 goats (23 males and 24 non-pregnant dry females) aged 1-4 years and weighing 18.87 ± 6.32 (930) kg. Packed cell volume (PCV), erythrocyte count and mean corpuscular volume (MCV) were also estimated. Low, medium and high EFP were based on MEF of 8 g/L, respectively. MEF of all the goats was 7.5 ± 0.6 (5.9-8.4) g/L. Phenotypic drift from sigmoidal to hyperbolic EOF curve was observed at the lower and upper limits of the phenotypic variation. Frequencies of occurrence of low, medium and high EFP were not different (p > 0.05) between males and females. Fragiligrams of low, medium and high EFP separated at erythrocyte fragilities of 10-70% and saline tonicity of 7-8 g/L. The saline concentrations causing fragilities of 10-70% differed (p 0.05) between MEF and MCV or PCV, and between PCV and MCV. In conclusion, phenotypic drift in EOF occurred in Sahel goats without influence by erythrocyte parameters and represented the physiological variability of EOF endpoint estimates that would serve as reference limits in evaluation of erythrocyte membrane defects.

Effects of sex and age on the osmotic stability of Sahel goat erythrocytes

Adaptation of goats to the arid and semi-arid environments may involve adjustments in erythrocyte osmoregulation. Sexual dimorphic and age-related effects on osmotic stability of the goat erythrocyte were investigated to determine physiological variations. Apparently healthy male (n = 23) and non-pregnant dry female (n = 24) Sahel goats, aged 1½–2, >2–2½, and >2½ years with mean body weights of 10.35–27.21 kg, were selected for the study from a semi-intensively managed flock. Heparinised venous blood of each goat was used to determine packed cell volume, erythrocyte count, mean corpuscular volume and osmotic fragility. Erythrocyte parameters did not vary with sex or age of the animal. Erythrocyte osmotic fragility (EOF), determined in hypotonic buffered saline, did not show sexual difference, but age elicited significant (p 1½–2 years, respectively. Body weights increased (p < 0.05; r = 0.96) with age, and 85.8 % weight gain occurred in the transition from age of <1 to 1–1½ years, whereas subsequent weight gains in other age transitions were 8.3, 18.8 and 9.9 %, respectively. Sex and age did not influence saline tonicities at the median erythrocyte fragility. The effect of age on EOF at minimal hypotonicity, occurring after a period of rapid growth, seemed to associate the change in membrane stability with actions of growth-promoting hormones on lipid metabolism which could have altered the lipid content and permeability of erythrocyte membrane.

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A case of congenital left brachium agenesis (amelia, brachiomelia monobrachium) in Sahel goat ecotype.

This rare case of amelia in a doe-goat was observed in Tarka local government area, Benue State, middle belt region of Nigeria. The congenital deformity consisted of complete agenesis of the affected fore limb; the defect is commonly unilaterally manifested. The present congenitally impaired goat was approximately one and a half years old, and was a second kiddling of a normal multiparous dam. The left fore limb was grossly vestigial in development, while the homologous right hoof was splayed; the hind limbs were anatomically normal. Radiographs revealed morphological aberrations in intergumentary, skeletal, vascular, nervous systems and musculature of the affected limb. Sahel goat is alien to this developmental syndrome and this is to the best of our knowledge--the first case report of left sided brachial agenesia, (amelia) in a doe-goat of this breed. By season of occurrence, the hypothesis of interplay between genetics, climate and environment at large in the pathogenesis of this hereditary anomaly is raised and supported by the abundance of phytoteratogens in alternative diets in the dry seasons. The condition is compatible with life but may contribute to reproductive and economic loss in farms.

Testicular and Related Size Evaluations in Nigerian Sahel Goats with Optimal Cauda Epididymal Sperm Reserve.

Testicular sizes of animals are important for identification of those with adequate sperm production. The aim of this study was to define the testicular and related size estimates that would be associated with optimal cauda epididymal sperm counts (ESC) in Sahel goats based on postmortem evaluations. A stratified quota sample population of 125 male goats inclusive of all testicular sizes was taken at a slaughterhouse in Maiduguri, Nigeria. The bucks were aged 18–30 months and weighed 17.04 ± 2.99 (12–25) kg. Body, testicular, and epididymal weights of each goat with other related size measurements were estimated. ESC was determined from homogenized tissue using a manual cytometer. At the cut-off ESC of >1.1 × 109 sperm heads, 66 (52.80%) of the goats had optimal ESC which was associated with testicular weight of 59.90 ± 16.10 (31.40–86.20) g, gonadosomatic index of 3.51 ± 0.69 (2.00–4.50) g/kg, and scrotal circumference of 19.07 ± 1.29 (17.00–21.80) cm. The size variables of the scrotum and testis correlated with one another and with the ESC. These findings provide data that may be used to anticipate adequate antemortem sperm reserve based on testicular size during preliminary selection of sires for breeding from a sexually mature Sahel buck population.

Sensitivity, specificity, predictive value and accuracy of ultrasonography in pregnancy rate prediction in Sahelian goats after progesterone impregnated sponge synchronization

Aim: This study was aimed to evaluate the sensitivity, specificity, predictive value and accuracy of ultrasonography in pregnancy rate (PR) prediction in Sahelian goats after progesterone impregnated sponge synchronization within the framework of caprine artificial insemination (AI) program in Fatick (Senegal). Materials and Methods: Of 193 candidate goats in AI program, 167 were selected (day 50) in six villages. Estrus was synchronized by progesterone impregnated sponges installed for 11 days. Two days before the time of sponge removal (day 4), each goat was treated with 500 IU of equine chorionic gonadotropin and 50 μg of dcloprostenol. All goats were inseminated (day 0) with alpine goat semen from France at 45±3 h after sponge removal (day 2). Real-time B-mode ultrasonography was performed at day 50, day 13, day 0, day 40 and day 60 post-AI. Results: Selection rate, estrus response rate, AI rate, PR at days 40 and days 60 were 86.53%; 71.85%; 83.34%; 51% and 68% (p<0.05) respectively. Value of sensitivity, specificity, positive and negative predictive value, accuracy, total conformity, conformity of correct positive, conformity of correct negative and discordance of pregnancy diagnosis by trans-abdominal ultrasonography (TU) were 98.03%; 63.26%; 73.52%; 3.12%; 81%; 81%; 50%; 31% and 19%, respectively. Conclusion: These results indicate that the TU can be performed in goats under traditional condition and emphasized the importance of re-examination of goats with negative or doubtful TU diagnoses performed at day 40 post-AI.

Influence of extracellular media's ionic strength on the osmotic stability of Sahel goat erythrocytes.

Heparinised blood was exposed to osmotic lysis in hypotonic buffered saline to evaluate erythrocyte membrane stability. When K3 EDTA blood was used, it added more to the ionic content of blood than heparin. The influence of suspending media's ionic strength on the osmotic stability of Sahel goat erythrocytes was investigated by replacing the ionic saline with non-ionic saccharide (sucrose or glucose) and assessing the effect of using EDTA blood instead of heparinised blood. The erythrocyte osmotic fragility curve in saline was hyperbolic even when the ionic concentration was reduced by 50% with saccharides. Haemolysis was higher with EDTA than heparinised blood at saline concentrations of 90 and 150-180 mosmol/L. The fragility curve was sigmoidal and shifted to the left when saline was completely substituted with a saccharide. The non-ionic saccharides increased erythrocyte osmotic resistance linearly (r=0.88; p<0.02) from median to minimal hyposmolarities (150-300 mosmol/L) and reduced the osmolyte concentration at median fragility by 36%. No effect occurred at <30-120 mosmol/L and >90% fragility; and saccharide concentrations were almost non-lytic at comparable saline concentrations evoking <10% haemolysis. Fragilities were neither affected by period (30-60 min) of incubation nor the type of saccharide used. In this study, the variation in osmotic stability of caprine erythrocytes was linked to ionic strength of the suspending extracellular media which seemed to exert an influence through transmembrane ion fluxes and regulatory volume changes in erythrocytes.

Caractéristiques phénotypiques de la chèvre du sahel au Niger par analyse des indices de primarité et des paramètres qualitatifs

In Niger, there are three goat breeds including two main ones: the Maradi red goat (17.5%) which has been the subject of numerous investigations and the Sahel goat (80%) which is little studied or unknown. Thus, to establish the phenotypic characteristics of the Sahel goat breed in Niger, investigations into qualitative parameters (appendices and pigmentation) by direct observation of animals were conducted in the northwestern part of the country (Tillabery, Tahoua and Niamey regions). Based on the voluntary participation of farmers, 443 goats (77% female, 39% with 4 pairs of permanent incisors and therefore considered adult) in 145 farms and 60 sites (7,38 ± 6,87 animals/site) were characterized. Analysis of primarity indices and multivariate analysis (ACM) emphasizes that there is no significant difference (P &lt; 0.05) between sexes for all quality parameters except the carrying of a beard (male 55%, female 41%). The parameters distribution is significantly different between regions except the type of horn (mostly ibex in all regions). Indeed, ears are mostly drooping in Tillabéry, stalked in Tahoua and Niamey and pigmentation is dominated by black eumélanique in Tahoua, chocolate eumélanique in Niamey and phaeomélanique in Tillabéry. Goats of the three regions are significantly different based on phenotypic qualitative parameters. But, generally, the goat study population has the characteristics of a primary population which offers great opportunities for genetic improvement.

Genetic polymorphism of α S1 casein in Guéra and Sahel goat

Summary The αS1 casein gene is one of the lacto protein genes, which are involved in the milk synthesis. The objective of this study was to identify genotypes of B and E alleles at the locus αS1 casein in the Guera and Sahel goat herds in Mali. These herds were located in the Regional Center of Agronomic Research and the Segala village in Kayes, Mali. A total of 101 blood samples (53 for Guera goat and 48 for Sahel goats) were collected and analysed. Alleles B and/or E, located on exon 19, of the αS1 casein gene were amplified using allele specific amplification polymerase chain reaction and analysed using 2 percent agarose gel electrophoresis. Results from this analysis identified three genotypes: BB, BE and EE with frequencies 0.77, 0.17 and 0.06 for the Guera goats. However, only the BB genotype was identified in the Sahel goats. The frequencies of alleles B and E in the Guera goats were 0.86 and 0.14, respectively, with an observed and expected heterozygotes of 0.08 and 0.12, respectively.

Pathological conditions associated with the male reproductive tract of the sahel bucks.

The study of pathological conditions of the male reproductive system is paramount to understanding reproductive inefficiency in the Sahel goat. In this study, 1048 Sahel bucks presented for slaughter at the Maiduguri metropolitan abattoir were evaluated for the presence of various pathological abnormalities of the reproductive system. A total incidence of 15.08% was recorded for various pathological conditions, with testicular, penile, and scrotal conditions having incidences of 7.82%, 4.80 and 2.50%, respectively. Bilateral testicular hypoplasia and atrophy and unilateral cryptorchidism accounted for incidences of 4.10%, 2.38%, and 1.24%, respectively, while paraphimosis and scrotal laceration had incidences of 1.72% and 1.05%, respectively. Age specific incidence of pathological conditions were not significant (P > 0.05) between bucks aged <1–1.5 and 2–2.5 years. However, bucks aged 3–3.5 year a had lower (P < 0.05) incidence of pathological conditions than other age groups. Histopathological evidence of inflammation, degeneration, and atrophy was observed in the testes, while inflammatory changes were observed in the prepuce.

The Weight Performance of the Sahel Goats in Guera, the Centre of Chad

The aim of the study was to measure the weight performance of Sahelian goats in the region of Guera in the Centre Chad. The weightings were carried out on young kids born in farms followed over four years. The frequency of the visits was twice a month from 0 to 2 months and monthly thereafter. The daily average gain at 30 days was 68 g in males and 63 g in females. These weights are lower than the observations made in other Sahelian zones of Chad. The weight development of kids according to the sex has a generally linear taken as a whole. Significant differences (P

Structure and Reproductive Performances of Sahelian Goats in the Guera Region, in Central Chad

The purpose of the study was to establish the structure of monitored animal farms and determine reproductive parameters of Sahelian goats in the Guera Region, in Central Chad. Data were collected through longitudinal survey in 27 observatory farms during three years using goats identified by numbered ear tags. The herds were composed on average of about 71% of females. The age pyramid covering all years showed a significant number of males aged between 0 - 1 year and perceptible fall thereafter. However, some stability was observed in the class of the 2 - 8 years old among females. The frequencies of accumulated kiddings showed that 44% of births occurred in the rainy season against 28% respectively in the cool dry and hot dry seasons. Obtained reproduction parameters were: a sex ratio of 0.51 in favor of males, a kidding interval of 10.6 months with significant differences (P < 0.05) according to the rank of birth, an age at first kidding of 16.5 months for females born in monitoring and an age of 20.3 months for all first-kidding, giving an apparent fertility rate of 145%, a fecundity rate of 116% and an abortion rate of 2%. The composition and structure of herds have highlighted the importance of females to ensure the reproducibility of goat production systems. The determined reproduction parameters are references for actions to improve goat rearing in this area.

Effect of Clinical Mastitis on the Gross Morphometry and Histopathology of Mammary Glands of Sahel Goats

The effect of clinical mastitis (unilateral, n=10 and bilateral, n=90) on the morphometry of mammary glands of Sahel goats was evaluated in comparison with those of apparently normal glands (n=20). The mammary glands were examined at slaughter and glandular measurements such as; glandular weight (GW), glandular mid circumference (GMC), glandular longitudinal length (GLL) and glandular teat lengths (GTL) were measured using a measuring tape. Tissue samples of the mammary gland were collected preserved in 10% buffered formalin, processed, embedded, section and stained with H&E and observed under light microscope at various magnifications for presence of pathological lesions. The mean GW was significantly higher (p < 0.05) in normal glands relative to the unilateral and bilateral mastitis. Mean GLL was significantly higher (p

Preliminary study of the digestive effects of Chenopodium ambrosioides Linn. (Chenopodiaceae) leaves extracts in goats

The effects of the crude aqueous extract of Chenopodium ambrosioides leaves on food intake and digestibility were evaluated with twelve Sahelian goats weighing about 25 kg. Three experimental groups, each consisting of three animals, were treated respectively with the dose of 1ml, 2ml and 4ml/kg of body weight. Treatment was daily and lasted three days. One control group, receiving the same diet as the experimental groups, was involved. The experiment revealed that the herbal extract induced a highly significant variation (p 0.01) in voluntary feed intake expressed in grams of dry matter (DM) from 366.67 g ± 86 (control group) to 631.67 g ± 106.37 (4ml/kg/BW treated group). Concerning digestibility, the results indicated an increase in the absorption of ash and fibre (39.65 % ± 2.65 to 51.38 % ± 4.91). But the digestibility of protein was only slightly influenced by the herbal extract. Animals treated with 4ml/kg/BW dosage had soft and pasty faeces. The aqueous extract of C. ambrosioides leaves would own interesting digestive effects in small ruminants in the fattening stage or those suffering from indigestion due to rumen stuffing. Further specialized studies may clarify those effects.

Evaluation of the effects of intravenous anaesthesia using a combination of ketamine - medetomidine in Sahel goats

The anaesthetic and cardiopulmonary effects of the combination of ketamine-medetomidine for total intravenous anaesthesia were evaluated in six sahel goats. The goats were administered a combination of ketamine (5mg/kg) and medetomidine (0.01mg/kg) intravenously. Baseline measurements of heart rate, respiratory rate and rectal temperature were taken prior to drug administration and repeatedly, at ten minutes interval after induction of anaesthesia until the end of anaesthesia. Heart rate decreased from baseline value of 73.5±5.7 beats/minute and reached its lowest value at 40 minutes (57.1± 4.8 beats/minute). Also respiratory rate decreased significantly from baseline value of 27.7±3.7 breaths/minute reaching its lowest value of 19.0 ± 4.6 breaths/minute at 50 minutes. Onset of anaesthesia was fast (1.2 ± 1.5min) and mean anaesthesia time was 97.1 ± 21.9min. Ketamine - medetomidine intravenous injection produced effective anaesthesia, muscle relaxation and immobilization in sahel goats. Recovery from anaesthesia was without complication.Keywords: Anaesthesia, Goats, Intravenous, Ketamine, Medetomidine

Caudo-Frontal Depression: A Landmark for Local Anasthesia in the Dehorning of Sahel Goats (Capra hircus)

The variation in shape and morphology of the head among animals even within the same family is common. Work to determine skull shape have been carried out by some workers. In horned animals, the position of the horns may differ and therefore necessitate the exploration of land marks for local anaesthesia. The caudofrontal depression of Sahel goats was studied to ascertain its involvement as a possible landmark for the deposition of local anaesthetic substances during dehorning process in this breed. The location of the depression was seen to be along the temporal crest, dorsal to the temporal fossa between the eye orbit and the horns. Data obtained indicates that it has a breadth of 1.01±0.09cm at the left side and of 0.97±0.14cm at the right side in female animals. Males had 0.84 ±

Effect of management practices on milk yield and live weight changes of indigenous breeds of goats supplemented with groundnut haulms and concentrate in sub humid zone of Nigeria

These studies were carried out at the Research farm of National Animal Production Research Institute, Shika to investigate the effect of management practices on the milk yield and live weight changes of grazing Red Sokoto and Sahelian goats as influenced by supplementation with groundnut haulms and concentrate. Experiment 1 involved 5 Red Sokoto goats with average weight of 27.3 ± 1.37Kg kept either on-farm or on-station and fed groundnut haulms or concentrate. The result showed that management had significant effect on average daily gain (ADG) of kid at 146.7± 0.62g (P&lt;0.01) and dam weight loss of -24.7±1.26g (P&lt;0.05). Milk yield was less sustained on farm. Week of lactation affected milk yield ( P&lt;0.01). In experiment 2, five goats of each of Red Sokoto or Sahelian breeds were randomly assigned to either groundnut haulms or concentrate as supplement. The results, showed that there were significant effect of breed (P&lt;0.0001) and week (P&lt;0.001) on milk yield, mean dam and kid weights respectively. The Red Sokoto dams had higher milk yield (414.1±47.19ml) than the Sahelian dams (203.2±46.61ml). Similarly, breed and type of supplementation fed showed significant difference (P&lt;0.005) on milk yield. Red Sokoto dams fed concentrate produced more milk (555.1±64.92ml) than Sahelian fed concentrate (295.2±69.51ml) or groundnut haulms (111.4±69.51ml). Also in comparing the kid growth performance between on-farm and on-station, The average daily gain of kids was 112.9g± 0.53 was significantly influenced by week of lactation, while dam lost an average of 11.7±0.65g indicating that kids managed on farm were heavier than those on station. However dam on-station lost less weight than those on-farms. The result showed that supplementation of grazing does with diets of protein source irrespective of management will improve milk yield and that heavier dams supported better kid growth.Keywords: On-farm, On-station, Performance, Red Sokoto, Sahelian..