Department of Animal Science

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Distribution and abundance of forest birds in Ghana
(Ostrich, 2000) Ntiamoa-Baidu, Y.; Owusu, E.H.; Asamoah, S.; Owusu-Boateng, K.
Forest reserves within the Ghanaian rain forest have been classified into categories (Condition I-VI) on the basis of their botanical importance and status of the vegetation. We present data on the distribution and abundance of avifauna of 28 Condition II and III forest reserves in southern Ghana based on line transect counts and mist-net captures. A total of 227 species were recorded for all the sites; species records for individual sites ranged from 78–119. The dominant groups in the overall survey were Muscicapidae (represented by 40 species), Pcynonotidae (21) and Cuculidae (12). The most abundant bird species in the Ghanaian forests were Yellow-whiskered Greenbul, Green Hylia, Green Pigeon and Olive Sunbird. Species encounter rates ranged from 16.7 to 50.7 species per km with individual bird encounter rates of 27.9 to 172.0 birds per km. Capture rates in mist-nets ranged from 1.2 to 3.9 birds per 100 metre net-hr (mnh). A total of 183 species were recorded in Condition II forest as compared with 167 in Condition III forests. The effects of forest condition and vegetation types on the total number of species recorded were, however, not statistically significant. The Similarity Index for bird communities within Condition II and III forests was 0.72. Bird species composition in the two forest types also differed: e.g., seven primary forest species, as well as 40% of the species associated with primary and matured secondary forest which were recorded in Condition II forests, were absent from Condition III forests. Bird communities of Moist Evergreen, Upland Evergreen and Moist semi-Deciduous were more similar than communities in the Wet Evergreen forest type. The implication of the results for conservation of the Ghana’s forests is discussed. © 2000, Taylor & Francis Group, LLC. All rights reserved.
Behavioural interactions between West African dwarf nanny goats and their single-born kids during the first 48 hours post-partum
(Applied Animal Behaviour Science, 2000-03) Addae, P.C.; Awotwi, E.K.; Oppong-Anane, K.; Oddoye, E.O.K.
West African dwarf nanny goats and their single-born kids were tested to find out their behavioural response to separation and their mutual recognition during the first 48 h post-partum. The tests were conducted at 18, 24, 36 or 48 h post partum. Chi-square analyses were used to determine whether age, sex and birth weight of kids as well as h partum and parity of dams had an effect on post-partum bahaviours. In a preliminary study where the kids were not prevented from sucking prior to the tests, the majority of kids (93%) and does (86%) exhibited apparant minimal concern to separation (i.e., had scores of less than 3) and also failed to seek each other. When the kids were prevented from sucking 2 h prior to the tests, the couple showed some response to separation and made attempts to seek each other. This suggests that in goats the state of the neonate's nourishment and the fullness of the dam's udder may be important factors that determine the willingness of the kid and the dam to seek each other when separated. The behavioural response of 48-h-old kids to separation from their dams when they had not sucked for 2 h was significantly higher (P < 0.05) than that of 18-h-old kids. The sex and birth-weight of 48-h-old kids did not affect their response to separation from their dams. Hours post-partum and parity of does did not affect their response to separation from their kids exhibiting even though the proportion of does the highest response was much higher in primiparous then multiparous animals (44% vs. 13%). Recognition of dams by kids was poor at 18 and 24 h with more than half (71%) the kids failing to recognize their dams. Dam recognition ability improved with age and at 48 h the majority of kids (88%) were able to recognize their dams. Does tested at 48 h post partum had better (P > 0.05) kid recognition than those tested at 18 and 24 h. The sex and birth weight of kids and the parity of dams had no effect on the mutual recognition of kids and their dams at 48 h post-partum. (C) 2000 Elsevier Science B.V.
An assessment of the safety of street foods in the Ga district, of Ghana; Implications for the spread of zoonoses
(Acta Tropica, 2000-07) King, L.K.; Awumbila, B.; Canacoo, E.A.; Ofosu-Amaah, S.
Street food refers to food and beverages prepared and sold by vendors in streets and other public places for immediate consumption. In Ghana street foods are sold at small eating places popularly known as 'chop bars'. Food safety studies were conducted on the premises of 160 'chop bars' in the Ga District of Ghana in July 1998. Only three (1.8%) of the proprietors met all the requirements (based on a five-point checklist) for basic hygiene. Twenty-four (15%) out of the 160 proprietors had access to potable water while the other 136 (85%) proprietors purchased water from vendors and six used pond water. These two latter sources of water were of poor microbiological quality (as shown by faecal coliform values which ranged from 1.0x102-1.9x105 cfu/ml). One hundred and five proprietors (65.6%) did not obtain their meat supply from an approved source. Factors influencing the purchase of meat from an approved source included the proximity of a chop bar to a slaughter facility, the conduct of meat inspection personnel and affordable user fees. Copyright (C) 2000 Elsevier Science B.V.
Behavioural interactions between West African dwarf nanny goats and their twin-born kids during the first 48 h post-partum
(Applied Animal Behaviour Science, 2000-07) Awotwi, E.K.; Oppong-Anane, K.; Addae, P.C.; Oddoye, E.O.K.
West African dwarf nanny goats and their twin-born kids were tested to determine their behavioural response to separation and their mutual recognition during the first 48 h post-partum. Does and their kids were given scores ranging from 1 to 5, depending on how they performed in the tests. Animals that showed maximum response and recognition ability were given a score of 5, while those with minimum response and recognition ability scored 1. The kids were prevented from sucking 2 h prior to the tests, which were carried out at 18, 24, 36 and 48 h post-partum. Chi-square procedure was used to determine whether age, sex and birthweight of kids as well as hours post-partum and parity of dams had any effect on these post-partum behaviours. Out of 48 twin-born kids tested, 32 (67%) responded actively to separation from dams (i.e. had scores of 3 or more). The age, sex and birthweight of kids did not significantly affect (P > 0.05) their response to separation from their dams. The hours post-partum and the parity of does also did not affect their response to separation from their kids. The dam recognition ability of twin-born kids was very poor. Out of a total of 48 kids tested, only 17 (35%) were able to recognize their dams (i.e. had scores of 3 or more). Even at 36 h, only four out of 14 (26%) could recognize their dams. It was only at 48 h that the majority of kids tested (i.e. 75%) successfully identified their dams. At 48 h, the dam recognition ability of kids was significantly better (P < 0.05) than that of 18-h-old kids. Sex and birthweight of 24-48-h-old twin-born kids did not significantly affect (P > 0.05) their ability to recognize their dams. The majority of does tested (i.e. 20 out of 24) were able to recognize their twin-born kids. The hour post-partum and parity of does did not significantly affect (P > 0.05) their kid recognition ability. (C) 2000 Elsevier Science B.V.
The prevalence of anti-Toxoplasma gondii antibodies in Ghanaian sheep and goats
(Acta Tropica, 2000-07) Van Der Puije, W.N.A.; Bosompem, K.M.; Canacoo, E.A.; Wastling, J.M.; Akanmori, B.D.
The enzyme-linked immunosorbent assay (ELISA) was used to detect anti-Toxoplasma gondii antibodies in 1258 small ruminants (732 sheep and 526 goats) sampled from 28 different locations in the three ecological zones of Ghana. The animals sampled had an overall seroprevalence of 30.5% (384 of the total). Sheep had a higher overall prevalence (33.2%) compared to the goats (26.8%). Animals sampled from the Coastal Savannah and the Forest zones had prevalences of 39.4% and 39.1%, respectively, which were significantly higher (P<0.01) than the prevalence recorded for the drier Guinea Savannah zone (20%). Prevalence of antibodies in female animals (35.8%) was significantly higher (P<0.01) than that for males (21.1%). Significant differences were also observed between breeds and age groups. The ELISA was found to be both highly sensitive (92%) and specific (91%) when compared to the IFAT, which was used as a reference test. Copyright (C) 2000 Elsevier Science B.V.
The seroprevalence of toxoplasmosis in pigs in Ghana
(Acta Tropica, 2000-07) Arko-Mensah, J.; Bosompem, K.M.; Canacoo, E.A.; Wastling, J.M.; Akanmori, B.D.
A serological survey of toxoplasmosis in pigs in Ghana was carried out between October 1997 and April 1998 in the three ecological zones of Ghana: the Coastal Savannah, the Forest Belt and the Guinea Savannah. Antibody against Toxoplasma gondii was measured in pig serum using a microplate-ELISA which had a sensitivity and specificity of 90.2 and 92.3%, respectively when compared with IFAT. A national seroprevalence of 39% was obtained in pigs, with the ecological distribution being 43.9, 30.5 and 42.5% for the Coastal Savannah, the Forest Belt and the Guinea Savannah, respectively. The age of the animal, the breed, the environmental conditions and the management practices appeared to be the major determinants of prevalence of antibodies against T. gondii. The prevalence of anti-T. gondii antibodies was found to increase with age (P<0.05). Pigs from the two Savannah zones had a significantly higher (P<0.05) antibody prevalence than those sampled from the Forest belt. Antibody prevalence (46.8%) in crossbreed pigs was significantly higher (P<0.05) than that of the exotic Large White breed (38.8%). Copyright (C) 2000 Elsevier Science B.V.
Seroprevalence of brucellosis in cattle and humans in the Akwapim-South district of Ghana: Public health implications
(Acta Tropica, 2000-07) Kubuafor, D.K.; Awumbila, B.; Akanmori, B.D.
A total of 183 cattle comprising 54 bulls, 53 milking cows, 76 heifers and 44 calves in the Akwapim-South district of Ghana were tested for antibodies against Brucella abortus using the Rose Bengal plate test. The results indicated that cattle in the Akwapim-South district were infected with Brucella with a mean seroprevalence of 6.6%. There was no difference in the seroprevalence either between females 11/129 (8.5%) and males 1/54 (1.9%), or among the three different breeds of cattle (Sanga, West African short horn (WASH) and white Fulani) in the study area. However, there was a significant increase in seropositivity with respect to age. A significant association between antibodies against Brucella and a history of abortions and retained placenta in cows indicated that brucellosis might be responsible for significant economic losses to farmers in the area. However, no evidence of human brucellosis was detected by antibody screening in selected risk groups. Copyright (C) 2000 Elsevier Science B.V.
Human behavioural factors implicated in outbreaks of human anthrax in the Tamale municipality of northern Ghana
(Acta Tropica, 2000-07) Opare, C.; Nsiire, A.; Awumbilla, B.; Akanmori, B.D.
The knowledge, attitude, beliefs and practices of cattle owners, herdsmen, butchers and meat consumers about anthrax were used to provide a better understanding of the major factors responsible for the frequent outbreaks of human anthrax in the Tamale municipality of northern Ghana. A total of 96% of the respondents, made up of 50 cattle owners, 50 herdsmen, 25 butchers and 125 consumers, knew of anthrax and the clinical signs indicative of anthrax in cattle. However, very few knew the causative agent and many attributed the disease to the supernatural. Eight percent of the respondents believed that herbal preparations could protect against human anthrax, while 9% indicated that they would seek help from traditional practitioners or herbalists, if they suspected anthrax. A significant proportion of respondents were of the view that animals, which had died of unknown causes could be eaten because they served as a source of inexpensive meat for the community, especially if the meat was cooked with herbs which was commonly thought to prevent anthrax. These attitudes, taken together with the low income of the population studied, made the consumption of meat from animals, which had died of unknown causes, an attractive option. This increased the vulnerability to human anthrax in an area with frequent anthrax outbreaks in livestock. The results of this study suggest that a public education campaign involving both veterinary and local health personnel on the actual cause and prevention of anthrax could reduce outbreaks of anthrax in people. Copyright (C) 2000 Elsevier Science B.V.
In vivo digestibility and effect of supplemental mucuna forage on treated rice straw degradation
(Small Ruminant Research, 2001-09) Adjorlolo, L.K.; Amaning-Kwarteng, K.; Fianu, F.K.
The objective of this study was to determine the digestibility of mucuna (Mucuna pruriens var utilis) forage and changes in the rumen degradation kinetics of a basal diet of sodium hydroxide (NaOH)-treated rice straw supplemented with mucuna forage. In vivo digestibility of the forage was determined by difference, using four rams (mean weight of 21.4 ± 1.22 kg) each fed either treated straw alone or supplemented with mucuna forage over two periods. In determining degradation kinetics, three rumen fistulated sheep (mean weight of 25.4 ± 1.81 kg) were fed treated rice straw only, or supplemented with 10, 20 or 25% mucuna forage. Dacron bags containing treated straw were incubated in the rumen for 3, 6, 12, 24, 48, 72 and 96 h. Dry matter (DM) and neutral detergent fibre (NDF) disappearance and degradation kinetics were determined. In vivo digestibility of DM and organic matter (OM) of treated straw (59.0 and 60.8%, respectively) were not significantly different from those of treated straw plus mucuna forage (61.5 and 63.3%, respectively). However, both were lower (P < 0.05) than the estimates for the forage only (70.8 and 71.8%, respectively). Crude protein digestibility (CPD) of treated straw plus mucuna diet (55.2%) was higher (P < 0.05) than for treated straw only (44.3%), and both significantly lower than that estimated for the forage (68.3%). Supplementation with 20 and 25% mucuna forage improved the rate of degradation of both DM (0.040 and 0.022, respectively) and NDF (0.038 and 0.023, respectively) of straw compared with the control of treated straw only (0.014 and 0.015%, respectively). Supplementation level of 20% elicited the highest degradation rate of both DM and NDF (0.040 and 0.038%, respectively). It was concluded that mucuna forage supplementation contributed towards improving NaOH-treated rice straw degradation in the rumen and thereby could help improve the utilisation of treated rice straw and similar low to medium quality roughages by ruminants in the tropics. © 2001 Elsevier Science B.V. All rights reserved.
The effect of age at mating on the behavioural interactions between primiparous Djallonke ewes and their lambs at 36 h post-partum
(Applied Animal Behaviour Science, 2001-12) Awotwi, E.K.; Canacoo, E.A.; Adogla-Bessa, T.; Oppong-Anane, K.; Oddoye, E.O.K.
Primiparous Djallonke ewes mated at 12, 15, 18 and 21 months and their single-born lambs were tested to determine their behavioural response to separation and their mutual recognition at 36 h post-partum. An analysis of variance was used to determine whether the age at mating had an effect on these post-partum behaviours. At 36 h, 92% of the lambs responded actively to separation from dams (i.e. had scores of 3 or more) while 90% of the ewes responded actively to separation from lambs. About 87% of the lambs were able to recognize their dams (i.e. had scores of 3 or more) while 90% of the ewes were able to recognize their lambs. The results showed that the age at mating and thus at lambing despite a slight effect on lamb birthweight had no significant effect on the response of lambs and their dams to separation. It also had no effect on the mutual recognition of mother and young. This suggests that the age at which ewes lamb for the first time has no influence on mother–young bond expression.
Preference of Sheep for Three Forms of Mucuna Forage and the Effect of Supplementation with Mucuna Forage on the Performance of Sheep
(Tropical Animal Health and Production, 2004-03) Adjorlolo, L.K.; Amaníng-Kwarteng, K.; Fianu, F.K.
Assessment of the preference of sheep for fresh, dried or ensiled forms of mucuna (Mucuna pruriens var utilis) forage was followed by investigations into the effect of supplementing straw-based diets with the forage. Four sheep were offered fresh, dried and ensiled forms of the forage in a cafeteria style to assess their preference. In the second experiment, 20 sheep were randomly assigned to four dietary treatments, namely, alkali-treated straw only (M0), treated straw supplemented with mucuna forage at 0.3% (M10), 0.6% (M20) or 0. 75% (M25) of body weight (approximately 10%, 20% and 25%, respectively, of the total dry matter intake). The daily feed intakes were determined and the sheep were weighed weekly for 10 weeks. The sheep showed a marked preference for fresh mucuna forage over either the dried or ensiled forms. The total dry matter intake increased by 15% and 21%, respectively, with M20 and M25. All the groups lost weight over the feeding period. However, only M0 gave weight losses during the second half of the feeding period. The feed conversion efficiency followed a trend similar to that for weight gains. M20 had the greatest effect on growth and feed conversion efficiency.
Polymorphism of dopamine receptor D4 exon I corresponding region in chicken
(Zoological Science, 2004-10) Sugiyama, A.; Inoue-Murayama, M.; Miwa, M.; Ohashi, R.; Kayang, B.B.; Mizutani, M.; Nirasawa, K.; Odai, M.; Minezawa, M.; Watanabe, S.; Ito, S.
In stockbreeding, there are indications that behavioral traits of livestock have an effect on breeding and production. If the variation in individual behavior is related to that in neurotransmitter-related genes such as in humans, it would be possible to breed pedigrees composed of individuals having behavioral traits that are useful to production and breeding using selection based on genotypes. In this study, we investigated the exon I region of dopamine receptor D4 (DRD4), in which variation is related to psychiatric disorder in humans, in major poultry species namely Japanese quail (Coturnix japonica), chicken (Gallus gallus), ring-necked pheasant (Phasianus colchicus) and helmeted guinea fowl (Numida meleagris). Furthermore, we investigated Japanese cormorant (Phalacrocorax capillatus) and Japanese jungle crow (Corvus macrorhynchos) as an out-group. In these species of birds, the repeat of proline was identified in the region corresponding to the human polymorphic region. The repeat number was 9 in Japanese quail, ring-necked pheasant and Japanese cormorant; 12 in helmeted guinea fowl; and 3 in Japanese jungle crow. However, no polymorphism was found in these species. In contrast, polymorphism was observed in chicken and two alleles with 8 and 9 repeats were identified. Although 9 repeats (allele 9) were predominant in most chicken breeds, Black Minorca had only 8 repeats (allele 8). Intra-breed polymorphism was found in 6 out of 12 breeds, and two alleles (alleles 8 and 9) were detected in these breeds. This polymorphism, which is the first to be reported on a neurotransmitter-related gene in birds, would contribute significant information for elucidation of differences in behavioral traits in chicken breeds.
Susceptibility of Amblyomma variegatum ticks to acaricides in Ghana
(Experimental and Applied Acarology, 2005-03) Natala, A.J.; Agyei, A.D.; Awumbila, B.
The susceptibility of unfed and fed stages of larvae, nymphs and adult females of Amblyomma variegatum ticks were tested using Shaw's filter paper dip method against four acaricides; chlorfenvinphos and dioxathion, chlorfenvinphos, gamma benzene hexachloride and amitraz at four different concentrations including the recommended dose rates. Based on their lethal concentrations (LC50 & LC90) chlorfenvinphos and dioxathion combined and chlorfenvinphos alone placed first and second, respectively, in all stages except at the unfed nymphal stage where gamma benzene hexachloride topped with a LC50 of 0.001629, while chlorfenvinphos and dioxathion combined and chlorfenvinphos alone had LC50 of 0.001794 and 0.002258, respectively. Amitraz appeared to have a quick knock-down effect on larvae and nymphs but at the recommended dose rate, showed no mortality of the ticks at that stage. However, at a concentration of 0.040%, amitraz showed a 100% inhibition of oviposition and hatching of laid eggs. Gamma benzene hexachloride produced only 66% inhibition of oviposition while chlorfenvinphos and dioxathion combined and chlorfenvinphos alone produced 100% inhibition of oviposition at their recommended dose rates. Fed nymphs were more susceptible than the unfed nymphs. Eggs laid by engorged female ovipositing ticks, applied with gamma benzene hexachloride, hatched. © Springer 2005.
Microsatellite mapping of QTL affecting growth, feed consumption, egg production, tonic immobility and body temperature of Japanese quail
(2005-06-08) Minvielle, F.; Kayang, B.B.; Inoue-Murayama, M.; Miwa, M.; Vignal, A.; Gourichon, D.; Neau, A.; Monvoisin, J.; Ito, S.
Abstract Background The Japanese quail (Coturnix japonica) is both an animal model in biology and a commercial bird for egg and meat production. Modern research developments with this bird, however, have been slowed down by the limited information that is available on the genetics of the Japanese quail. Recently, quail genetic maps with microsatellites and AFLP have been produced which open the way to comparative works with the chicken (Gallus gallus), and to QTL detection for a variety of traits. The purpose of this work was to detect for the first time QTL for commercial traits and for more basic characters in an F2 experiment with 434 female quail, and to compare the nature and the position of the detected QTL with those from the first chicken genome scans carried out during the last few years. Results Genome-wide significant or suggestive QTL were found for clutch length, body weight and feed intake on CJA01, age at first egg and egg number on CJA06, and eggshell weight and residual feed intake on CJA20, with possible pleiotropy for the QTL affecting body weight and feed intake, and egg number and age at first egg. A suggestive QTL was found for tonic immobility on CJA01, and chromosome-wide significant QTL for body temperature were detected on CJA01 and CJA03. Other chromosome-wide significant QTL were found on CJA02, CJA05, CJA09 and CJA14. Parent-of-origin effects were found for QTL for body weight and feed intake on CJA01. Conclusion Despite its limited length, the first quail microsatellite map was useful to detect new QTL for rarely reported traits, like residual feed intake, and to help establish some correspondence between the QTL for feed intake, body weight and tonic immobility detected in the present work and those reported on GGA01 in the chicken. Further comparative work is now possible in order to better estimate and understand the genetic similarities and differences of these two Phasianidae species.
Mapping of plumage colour and blood protein loci on the microsatellite linkage map of the Japanese quail
(Animal Genetics, 2005-10) Miwa, M.; Inoue-Murayama, M.; Kayang, B.B.; Vignal, A.; Minvielle, F.; Monvoisin, J.L.; Takahashi, H.; Ito, S.
The objective of this work was to map classical markers (plumage colours and blood proteins) on the microsatellite linkage map of the Japanese quail (Coturnix japonica). The segregation data on two plumage colours and three blood proteins were obtained from 25 three-generation families (193 F2 birds). Linkage analysis was carried out for these five classical markers and 80 microsatellite markers. A total of 15 linkage groups that included the five classical loci and 69 of the 80 microsatellite markers were constructed. Using the BLAST homology search against the chicken genome sequence, three quail linkage groups, QL8, QL10 and QL13, were suggested to be homologous to chicken chromosomes GGA9, GGA20 and GGA24, respectively. Two plumage colour loci, black at hatch (Bh) and yellow (Y), and the three blood protein loci, transferrin (Tf), haemoglobin (Hb-1) and prealbumin-1 (Pa-1), were assigned to CJA01, QL10, QL8, CJA14 and QL13, respectively. © 2005 International Society for Animal Genetics.
Mapping of panda plumage color locus on the microsatellite linkage map of the Japanese quail
(2006-01-12) Miwa, Mitsuru; Inoue-Murayama, Miho; Kobayashi, Naoki; Kayang, Boniface B; Mizutani, Makoto; Takahashi, Hideaki; Ito, Shin'ichi
Abstract Background Panda (s) is an autosomal recessive mutation, which displays overall white plumage color with spots of wild-type plumage in the Japanese quail (Coturnix japonica). In a previous study, the s locus was included in the same linkage group as serum albumin (Alb) and vitamin-D binding protein (GC) which are mapped on chicken (Gallus gallus) chromosome 4 (GGA4). In this study, we mapped the s locus on the microsatellite linkage map of the Japanese quail by linkage analysis. Results Segregation data on the s locus were obtained from three-generation families (n = 106). Two microsatellite markers derived from the Japanese quail chromosome 4 (CJA04) and three microsatellite markers derived from GGA4 were genotyped in the three-generation families. We mapped the s locus between GUJ0026 and ABR0544 on CJA04. By comparative mapping with chicken, this locus was mapped between 10.0 Mb and 14.5 Mb region on GGA4. In this region, the endothelin receptor B subtype 2 gene (EDNRB2), an avian-specific paralog of the mammalian endothelin receptor B gene (EDNRB), is located. Because EDNRB is responsible for aganglionic megacolon and spot coat color in mouse, rat and equine, EDNRB2 is suggested to be a candidate gene for the s locus. Conclusion The s locus and the five microsatellite markers were mapped on CJA04 of the Japanese quail. EDNRB2 was suggested to be a candidate gene for the s locus.
Integrated maps in quali (Coturnix japonica) confirm the high degree of synteny conservation with chicken (Gallus gallus) despite 35 million years of divergence
(BMC Genomics, 2006-05) Kayang, B.B.; Fillon, V.; Inoue-Murayama, M.; Miwa, M.; Leroux, S.; Fève, K.; Monvoisin, J.-L.; Pitel, F.; Vignoles, M.et.al
Background: By comparing the quail genome with that of chicken, chromosome rearrangements that have occurred in these two galliform species over 35 million years of evolution can be detected. From a more practical point of view, the definition of conserved syntenies helps to predict the position of genes in quail, based on information taken from the chicken sequence, thus enhancing the utility of this species in biological studies through a better knowledge of its genome structure. A microsatellite and an Amplified Fragment Length Polymorphism (AFLP) genetic map were previously published for quail, as well as comparative cytogenetic data with chicken for macrochromosomes. Quail genomics will benefit from the extension and the integration of these maps. Results: The integrated linkage map presented here is based on segregation analysis of both anonymous markers and functional gene loci in 1,050 quail from three independent F2 populations. Ninety-two loci are resolved into 14 autosomal linkage groups and a Z chromosome-specific linkage group, aligned with the quail AFLP map. The size of linkage groups ranges from 7.8 cM to 274.8 cM. The total map distance covers 904.3 cM with an average spacing of 9.7 cM between loci. The coverage is not complete, as macrochromosome CJA08, the gonosome CJAW and 23 microchromosomes have no marker assigned yet. Significant sequence identities of quail markers with chicken enabled the alignment of the quail linkage groups on the chicken genome sequence assembly. This, together with interspecific Fluorescence In Situ Hybridization (FISH), revealed very high similarities in marker order between the two species for the eight macrochromosomes and the 14 microchromosomes studied. Conclusion: Integrating the two microsatellite and the AFLP quail genetic maps greatly enhances the quality of the resulting information and will thus facilitate the identification of Quantitative Trait Loci (QTL). The alignment with the chicken chromosomes confirms the high conservation of gene order that was expected between the two species for macrochromosomes. By extending the comparative study to the microchromosomes, we suggest that a wealth of information can be mined in chicken, to be used for genome analyses in quail. © 2006 Kayang et al; licensee BioMed Central Ltd.
Search for QTL affecting the shape of the egg laying curve of the Japanese quail
(2006-05-05) Minvielle, Francis; Kayang, Boniface B; Inoue-Murayama, Miho; Miwa, Mitsuru; Vignal, Alain; Gourichon, David; Neau, André; Monvoisin, Jean-Louis; Ito, Shin' ichi
Abstract Background Egg production is of critical importance in birds not only for their reproduction but also for human consumption as the egg is a highly nutritive and balanced food. Consequently, laying in poultry has been improved through selection to increase the total number of eggs laid per hen. This number is the cumulative result of the oviposition, a cyclic and repeated process which leads to a pattern over time (the egg laying curve) which can be modelled and described individually. Unlike the total egg number which compounds all variations, the shape of the curve gives information on the different phases of egg laying, and its genetic analysis using molecular markers might contribute to understand better the underlying mechanisms. The purpose of this study was to perform the first QTL search for traits involved in shaping the egg laying curve, in an F2 experiment with 359 female Japanese quail. Results Eight QTL were found on five autosomes, and six of them could be directly associated with egg production traits, although none was significant at the genome-wide level. One of them (on CJA13) had an effect on the first part of the laying curve, before the production peak. Another one (on CJA06) was related to the central part of the curve when laying is maintained at a high level, and the four others (on CJA05, CJA10 and CJA14) acted on the last part of the curve where persistency is determinant. The QTL for the central part of the curve was mapped at the same position on CJA06 than a genome-wide significant QTL for total egg number detected previously in the same F2. Conclusion Despite its limited scope (number of microsatellites, size of the phenotypic data set), this work has shown that it was possible to use the individual egg laying data collected daily to find new QTL which affect the shape of the egg laying curve. Beyond the present results, this new approach could also be applied to longitudinal traits in other species, like growth and lactation in ruminants, for which good marker coverage of the genome and theoretical models with a biological significance are available.
Long-term feed intake regulation in sheep is mediated by opioid receptors
(Journal of Animal Science 1(85): 111-117, 2007) Obese, F.Y.; Whitlock, B.K.; Steele, B.P.; Buonomo, F.C.; Sartin, J.L.
These experiments were conducted to determine if 1) syndyphalin-33 (SD33), a μ-opioid receptor ligand, affects feed intake; 2) SD33 effects on feed intake are mediated by actions on opioid receptors; and 3) its activity can counteract the reduction in feed intake associated with administration of bacterial endotoxin. In Exp. 1, 5 mixed-breed, castrate male sheep were housed indoors in individual pens. Animals had ad libitum access to water and concentrate feed. Saline (SAL; 0.9% NaCl) or SD33 (0.05 or 0.1 μmol/kg of BW) was injected i.v., and feed intake was determined at 2, 4, 6, 8, 24, and 48 h after the i.v. injections. Both doses of SD33 increased (at least P < 0.01) feed intake at 48 h relative to saline. In Exp. 2, SAL + SAL, SAL + SD33 (0.1 μmol/kg of BW), naloxone (NAL; 1 mg/kg of BW) + SAL, and NAL + SD33 were injected i.v. Food intake was determined as in Exp. 1. The SAL + SD33 treatment increased (P = 0.022) feed intake at 48 h relative to SAL + SAL. The NAL + SAL treatment reduced (at least P < 0.01) feed intake at 4, 6, 8, 24, and 48 h, whereas the combination of NAL and SD33 did not reduce feed intake at 24 (P = 0.969) or 48 h (P = 0.076) relative to the saline-treated sheep. In Exp. 3, sheep received 1 of 4 treatments: SAL + SAL, SAL + 0.1 μmol of SD33/kg of BW, 0.1 μg of lipopolysaccharide (LPS)/kg of BW + SAL, or LPS + SD33, and feed intake was monitored as in Exp. 1. Lipopolysaccharide suppressed cumulative feed intake for 48 h (P < 0.01) relative to saline control, but SD33 failed to reverse the reduction in feed intake during this period. These data indicate that SD33 increases feed intake in sheep after i.v. injection, and its effects are mediated via opioid receptors. However, the LPS-induced suppression in feed intake cannot be overcome by the opioid receptor ligand, SD33.
Reproductive characteristics of the female grasscutter (Thryonomys swinderianus) and formulation of colony breeding strategies
(Livestock Research for Rural Development, 2007-12) Addo, P.G.; Awumbila, B.; Awotwi, E.; Ankrah, N.A.
The reproductive characteristics of 34 female grasscutters (Thryonomys Swinderianus) were investigated to identify common features that could be used to formulate breeding strategies for grasscutters in captivity. The female's ability to manifest an oestrous cycle, mate, conceive, deliver and wean its young in captivity, as well as elicit signs of successful mating, conception and imminent parturition were investigated. Thirty-one (91.2%) females cycled erratically and mated within 2 weeks of pairing with the male, irrespective of the oestrous phase. Twenty-seven (87.1%) conceived, 2 aborted and 25 (92.6%) gave birth after 148-157 days to 2-6 pups per litter, totalling 98 neonates, which included 9 stillborn. The remaining 89 pups were successfully weaned at 6 weeks of age. All mated females presented post-mating vulval congestion, while those that became pregnant bled intermittently on the 32nd-38 th day after mating, Eleven (44%) of the pregnant females adopted the 'penguin posture' 2-3 days before delivery. The variations among the grasscutters with respect to all the parameters investigated (except the oestrous cycle length) were statistically not significant; suggesting that a common breeding programme could be put in place for management of grasscutters in captivity. Furthermore, since mating, pregnancy and imminent parturition were accompanied by visible cues, they could be used to enhance the practical management of the breeding colonies. In conclusion, the overall findings of this study showed that though the grasscutters of the study are still undergoing domestication, they exhibit fairly uniform characteristics and therefore the formulation of a common breeding programme is practicable.

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