Estimating Additive and Dominance Variance for Litter Traits in Purebred California White Kits Using Different Models

Reproductive and growth records of 82 purebred California white kits were used to estimate additive and dominance genetic variances using BULPF90PC-PACK. Estimates were obtained for litter size at birth (LSB) and at weaning (LSW); litter weight at birth (LWB) and at weaning (LWW); individual kit weight at birth (IKWB)and at weaning (IKWW)as well as neonatal (Nil) and morlality at weaning (WM). Two mixed model equations were adopted. The first model included fixed effects and random effects identifying inbreeding depression, additive gene effect and permanent environmental effects. The second model was similar to the first model, but included the dominance genotypic effect. Estimates of heritability from sire component of variance for LSB, LSW, LWB, LWW, IKWB and IKWW were 0.4810.53,0.41/0.44, 0.5010.55 ,0.491NA, 0.4410.47 and 0.48/0.56 from model 1 and 2 respectively. Proportions of dominance effect to total phenotypic variance from the dominance model were 0.222, 0.453, 0.206, 0.349, 0.417 and 0.521 for LSB, LSW, LWB, LWW, IKWB and IKWW respectively. Dominance effects, which are not transferable through gametes (haploid entities) but are recreated at random in the offspring, were found to influence the litter traits analyzed. Therefore, genetic evaluation with the dominance model (Model 2) was found more appropriate than the animal model (Model 1). Keywords: Additive, Dominance, Heritability, Inbreeding, Rabbi

Relationship Between Gestation Length and Birth Weight in Nigerian Sheep and Their Crosses

Effect of genotype and birth weight on gestation length was evaluated using Nigerian breeds of sheep and their crosses. The study was carried out at the Sheep Project Unit of Small Ruminant Research Programme (SRRP) of National Animal Production Research Institute (NAPRI), Ahmadu Bello University, Shika-Zaria. The sheep breeds used were Balami, Uda and Yankasa. Heat (estrus) detection was carried out twice daily; in the morning (07:00-08:00 hours); and in the evening (16:00-17:00 hours) using apron fitted rams to pick does on heat. A total of 56 lambs were used for this study. The data obtained were subjected to analysis of variance using General Linear Model and Correlation Procedure of SAS. All the genotypes had similar gestation length with values between 150.3±0.61 days and 153.3±0.60 days, except for Balami pure breed (BAL X BAL) lambs that recorded a shorter gestation length (137.1±0.81 days). There was a wide variation in the birth weight of lambs with the crosses between Balami rams and Yankasa ewes recording a distinct birth weight of 3.5±0.08 kg while the crosses obtained using Yankasa rams on Uda and Balami ewes gave the lowest birth weights (1.7±0.19 and 1.4±0.18, respectively). Sex and litter type have no significant effect (P>0.05) on gestation length. Birth weight was however affected by sex of lambs and their litter type. Litter type was negatively correlated with birth weight (-0.372). Gestation length had a low and non-significant relationship with birth weight; litter type and lamb genotype. Lamb genotype does not have a significant relationship with litter type. Genetic improvement of Nigeria sheep breed is possible if the resources of within and between breed is exploited. Selection for a reduction in gestation length may indirectly increase prolificacy. (Animal Production 12(3): 135-138 (2010)Key Words : gestation length, birth weight, Nigerian Shee

Relationship Between Gestation Length and Birth Weight in Nigerian Sheep and Their Crosses

Effect of genotype and birth weight on gestation length was evaluated using Nigerian breeds of sheep and their crosses. The study was carried out at the Sheep Project Unit of Small Ruminant Research Programme (SRRP) of National Animal Production Research Institute (NAPRI), Ahmadu Bello University, Shika-Zaria. The sheep breeds used were Balami, Uda and Yankasa. Heat (estrus) detection was carried out twice daily; in the morning (07:00-08:00 hours); and in the evening (16:00-17:00 hours) using apron fitted rams to pick does on heat. A total of 56 lambs were used for this study. The data obtained were subjected to analysis of variance using General Linear Model and Correlation Procedure of SAS. All the genotypes had similar gestation length with values between 150.3±0.61 days and 153.3±0.60 days, except for Balami pure breed (BAL X BAL) lambs that recorded a shorter gestation length (137.1±0.81 days). There was a wide variation in the birth weight of lambs with the crosses between Balami rams and Yankasa ewes recording a distinct birth weight of 3.5±0.08 kg while the crosses obtained using Yankasa rams on Uda and Balami ewes gave the lowest birth weights (1.7±0.19 and 1.4±0.18, respectively). Sex and litter type have no significant effect (P>0.05) on gestation length. Birth weight was however affected by sex of lambs and their litter type. Litter type was negatively correlated with birth weight (-0.372). Gestation length had a low and non-significant relationship with birth weight; litter type and lamb genotype. Lamb genotype does not have a significant relationship with litter type. Genetic improvement of Nigeria sheep breed is possible if the resources of within and between breed is exploited. Selection for a reduction in gestation length may indirectly increase prolificacy. (Animal Production 12(3): 135-138 (2010

Familial deletion 18p syndrome: case report

BACKGROUND: Deletion 18p is a frequent deletion syndrome characterized by dysmorphic features, growth deficiencies, and mental retardation with a poorer verbal performance. Until now, five families have been described with limited clinical description. We report transmission of deletion 18p from a mother to her two daughters and review the previous cases. CASE PRESENTATION: The proband is 12 years old and has short stature, dysmorphic features and moderate mental retardation. Her sister is 9 years old and also has short stature and similar dysmorphic features. Her cognitive performance is within the borderline to mild mental retardation range. The mother also presents short stature. Psychological evaluation showed moderate mental retardation. Chromosome analysis from the sisters and their mother revealed the same chromosomal deletion: 46, XX, del(18)(p11.2). Previous familial cases were consistent regarding the transmission of mental retardation. Our family differs in this regard with variable cognitive impairment and does not display poorer verbal than non-verbal abilities. An exclusive maternal transmission is observed throughout those families. Women with del(18p) are fertile and seem to have a normal miscarriage rate. CONCLUSION: Genetic counseling for these patients should take into account a greater range of cognitive outcome than previously reported

African Communitarianism and Difference

There has been the recurrent suspicion that community, harmony, cohesion, and similar relational goods as understood in the African ethical tradition threaten to occlude difference. Often, it has been Western defenders of liberty who have raised the concern that these characteristically sub-Saharan values fail to account adequately for individuality, although some contemporary African thinkers have expressed the same concern. In this chapter, I provide a certain understanding of the sub-Saharan value of communal relationship and demonstrate that it entails a substantial allowance for difference. I aim to show that African thinkers need not appeal to, say, characteristically Euro-American values of authenticity or autonomy to make sense of why individuals should not be pressured to conform to a group’s norms regarding sex and gender. A key illustration involves homosexuality

Prevalence, years lived with disability, and trends in anaemia burden by severity and cause, 1990-2021: findings from the Global Burden of Disease Study 2021

Background Anaemia is a major health problem worldwide. Global estimates of anaemia burden are crucial for developing appropriate interventions to meet current international targets for disease mitigation. We describe the prevalence, years lived with disability, and trends of anaemia and its underlying causes in 204 countries and territories. Methods We estimated population-level distributions of haemoglobin concentration by age and sex for each location from 1990 to 2021. We then calculated anaemia burden by severity and associated years lived with disability (YLDs). With data on prevalence of the causes of anaemia and associated cause-specific shifts in haemoglobin concentrations, we modelled the proportion of anaemia attributed to 37 underlying causes for all locations, years, and demographics in the Global Burden of Disease Study 2021. Findings In 2021, the global prevalence of anaemia across all ages was 24·3% (95% uncertainty interval [UI] 23·9–24·7), corresponding to 1·92 billion (1·89–1·95) prevalent cases, compared with a prevalence of 28·2% (27·8–28·5) and 1·50 billion (1·48–1·52) prevalent cases in 1990. Large variations were observed in anaemia burden by age, sex, and geography, with children younger than 5 years, women, and countries in sub-Saharan Africa and south Asia being particularly affected. Anaemia caused 52·0 million (35·1–75·1) YLDs in 2021, and the YLD rate due to anaemia declined with increasing Socio-demographic Index. The most common causes of anaemia YLDs in 2021 were dietary iron deficiency (cause-specific anaemia YLD rate per 100 000 population: 422·4 [95% UI 286·1–612·9]), haemoglobinopathies and haemolytic anaemias (89·0 [58·2–123·7]), and other neglected tropical diseases (36·3 [24·4–52·8]), collectively accounting for 84·7% (84·1–85·2) of anaemia YLDs. Interpretation Anaemia remains a substantial global health challenge, with persistent disparities according to age, sex, and geography. Estimates of cause-specific anaemia burden can be used to design locally relevant health interventions aimed at improving anaemia management and prevention. Funding Bill & Melinda Gates Foundation

Genetic parameter estimates (full sib and half sib analysis) of fertility and hatchability in two strains of Rhode Island chickens

A study was conducted to estimate the genetic parameters of fertility and hatchability in two strains of Rhode Island Red (RIR) Chickens denoted as Strain A and Strain B respectively using the full-sib (sire +dam variance) and maternal half-sib (dam variance) components. The birds were obtained from the selected populations of RIR Chickens kept at the poultry breeding programme of National Animal Production Research Institute, Shika, Zaria, Nigeria. Settable eggs were collected from mating 28 cocks to 252 hens in a ratio of 1cock:9 hens from each strain. Eggs were pedigreed according to sire and dam. Results showed that values obtained for number of egg set (EGGSET), number of fertile eggs (NFERT), number of hatched chicks (NHATCH), percentage of chicks hatched from total eggs set (PHATCH) and percentage of chicks hatched from fertile eggs (PHATCHBL) were all higher in strain A than strain B. Heritability estimates obtained from the full-sib and maternal half-sib analysis ranged from medium to high for the two strains (0.24-0.96). The maternal half sib estimates were higher (0.40-0.96) than the estimates obtained from full sibs (0.24- 0.48). Genetic and phenotypic correlations obtained for both strains were positive and similar regardless of method of estimation. Genetic correlations between EGGSET and PFERT were low in strain A using both full-sib and maternal half-sib analyses (0.09-0.14). Phenotypic correlations between EGGSET and PFERT, PHATCH and PHATCHBL were also low in both strains and regardless of method of analyses. Moderate to high heritability estimates suggest that genetic improvement can be obtained by selection of these reproductive traits. The full-sib analysis for estimating heritability will be preferred since it is assumed that only additive genetic variance contributes to the covariance between family members. Keywords: Rhode Island Red Chickens, genetic parameters, fertility, hatchabilit

Effect of quantitative feed restriction on pullet development and subsequent egg production

The effect of quantitative feed restriction during rearing on mature body weight and subsequent egg production of pullets was investigated in two experiments. All the birds in the two experiments were fed ad libitum on 20% crude protein and! 649kcal/kg ME diet from 0-8 weeks of age. From 9-20 weeks, feed was denied the birds for a day after one or two days of ad lib feeding, or restricted to 75% of ad lib intake by the control birds. Results of these two studies showed that with restriction, a significant decrease in growth rate was obtained at 20 weeks and 36 weeks. However, the feed regimen imposed on the birds during the growing period did not have any significant effect on sexual maturity nor peak production levels. Hen-day and hen-housed production levels as well as cost of feed per unit weight or dozen eggs, were not significantly affected by the treatments. These studies showed that when growing birds are restricted in quantity of feed fed, they respond with a reduction in mature weight, but the laying phase is unaffected. Key words: Feed restriction, pullet, egg productio

Diallel Crossing of Three Rabbit Breeds in Northern Guinea Savannah Zone of Nigeria: 1. Genetic Parameter Estimates for Litter Traits

Data on litter traits of 202 progeny from purebred population of Chinchilla (CHC), ew Zealand White (ZW) and California White (CAW) breeds of rabbits were used to estimate heritability and repeatability for litter traits. The litter traits considered were gestation length (GL), litter size (LS) and litter weight (LW) from birth to weaning. The variance components used for estimation of heritability were obtained through VARCOMP Procedure of SAS. Repeated records of dams were used to estimate repeatability. Heritability estimates for litter size from birth to weaning were high (0.49–0.64) in the CHC breed, while the estimates for litter weight were moderate to high (0.34–0.52). In the ZW and CAW breeds, moderate to high heritability estimates for litter size and litter weight (0.33–0.46 and 0.28–0.41); (0.31–0.42 and 0.32–0.41) were observed from birth to weaning. Estimates of repeatability for all traits observed in this study for all breeds were moderate to high. Traits with moderate to high repeatability observed in this study imply that great reliability can be put on selection or culling of does and bucks for such trait, based on one or two records. Lowly heritable traits obtained can be improved upon by crossbreeding. Moderately heritable traits on the other hand could be improved upon by combining pedigree and individual selection. While individual selection can be adopted to improve the highly heritable characters observed.Keywords: Diallel cross, Genetic parameters, Rabbits, Litter traits, Zari

Influence of breed and environmental factors on litter parameters of rabbits raised in a semi-humid environment

The influence of breed and environmental factors such as season, temperature, relative humidity, sunshine hours and wind speed on litter parameters of rabbits raised in a semi-humid environment was investigated using two hundred and twenty four (224) litter records collected between 1991 and 1997. New Zealand White does kindled significantly (P<0.05) larger and heavier litter at birth than the other breeds. Crossbred does produced kits with significantly higher preweaning daily gain and lower neonatal mortality compared with the purebred does. Chinchilla and Crossbred does raised kits with significantly (P<0.05) heavier weaning weights than New Zealand White and Californian does. There was a non-significant effect of season on litter site at birth, kits alive at birth and neonatal mortality. Does that kindled in the cool-wet season had significantly (P<0.05) higher litter birth weight and average kit birth weight compared with does that kindled in the cold-dry and hot-dry seasons. Kits kindled in the hot-dry season had significantly higher preweaning litter daily gain and lower preweaning mortality than those kindled in the other seasons. Does that kindled in the hot-dry and cool-wet seasons weaned more kits than those that kindled in the cold-dry season. There was a significant (P<0.05) negative correlation between maximum temperature and litter size alive at birth, litter birth weight, litter weaning weight, average weaning weight and litter size at weaning. Rainfall and relative humidity had significant positive correlation with average birth weight, while, wind speed was positively correlated with average weaning weight. This study indicates that the best season for rabbit breeding in the semi-humid environment is the hot-dry (February-May) season. Maximum temperature was also observed to be more critical to rabbit reproduction as it influenced negatively more litter parameters than other environmental factors studied.Keywords: Environment, Season, Litter parameters, Rabbits