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In general, livestock and fish farming systems in developing countries tend to be highly diverse in terms of agro-ecological conditions and market orientation. There are no studies that have investigated if and how this diversity translates to varying preferences for breeding objective traits. This is particularly important for breeding programmes that are organized on a national level (e.g. government-supported nucleus breeding programmes). The aim of this study was to investigate whether Nile tilapia farmers with diverse production systems and economic constraints have different preferences for breeding objective traits. The second objective was to derive a consensus breeding goal, using weighted goal programming that could be used for a national breeding programme for Nile tilapia. A survey was conducted among 100 smallholder Nile tilapia farmers in Kenya to obtain preference values for traits of economic importance, by using multiple pairwise comparisons. Individual and group preference values were estimated using analytical hierarchy process. Low-income farmers preferred harvest weight, while medium- and high-income farmers preferred growth rate and survival. Grouping farmers according to market objective (fingerling production or fattening) showed that fingerling producers preferred growth rate and survival, while fattening farmers preferred harvest weight, height and thickness. Weighted goal programming was used to obtain consensus preference values, and these were used to derive desired gains for a breeding goal of a national breeding programme that takes into account the diversity of smallholder production systems. [ABSTRACT FROM AUTHOR]

This study compares two genetic management scenarios for species kept in herds, such as deer. The simulations were designed so that their results can be extended to a wide range of zoo populations. In the first scenario, the simulated populations of size 3 × 20, 6 × 40 or 20 × 60 (herds × animals in herd) were managed with a rotational mating ( RM) scheme in which 10%, 20% or 50% of males were selected for breeding and moved between herds in a circular fashion. The second scenario was based on optimal contribution theory ( OC). OC requires an accurate pedigree to calculate kinship; males were selected and assigned numbers of offspring to minimize kinship in the next generation. RM was efficient in restriction of inbreeding and produced results comparable with OC. However, RM can result in genetic adaptation of the population to the zoo environment, in particular when 20% or less males are selected for rotation and selection of animals is not random. Lowest rates of inbreeding were obtained by combining OC with rotation of males as in the RM scheme. RM is easy to implement in practice and does not require pedigree data. When full pedigree is available, OC management is preferable. [ABSTRACT FROM AUTHOR]

We investigated genetic and morphological diversity and population structure of 14 traditional sheep populations originating from four ecological zones in Ethiopia (sub-alpine, wet highland, sub-humid lowland and arid lowland). All animals ( n = 672) were genotyped for 17 microsatellite markers and scored for 12 morphological characters. The sheep were initially classified as fat-tailed (11 populations), thin-tailed (one population) and fat-rumped sheep (two populations). These classifications are thought to correspond to three consecutive introduction events of sheep from the Near-East into East Africa. For the 14 populations, allelic richness ranged from 5.87 to 7.51 and expected heterozygosity ( HE) from 0.66 to 0.75. Genetic differentiations ( FST values) between all pairs of populations, except between sub-alpine populations, were significantly different from zero ( P < 0.001). Cluster analysis of morphological characters and a dendrogram constructed from genetic distances were broadly consistent with the classification into fat-tailed, thin-tailed and fat-rumped sheep. Bayesian cluster analysis using microsatellite markers indicated that there has been further genetic differentiation after the initial introduction of sheep into Ethiopia. Investigation of factors associated with genetic variation showed that an isolation-by-distance model, independently of other factors, explained most of the observed genetic variation. We also obtained a strong indication of adaptive divergence in morphological characters, patterns of morphological variation being highly associated with ecology even when the effect of neutral genetic divergence ( FST) was parcelled out in partial Mantel tests. Using a combination of FST values, Bayesian clustering analysis and morphological divergence, we propose a classification of Ethiopian sheep into six breed groups and nine breeds. [ABSTRACT FROM AUTHOR]

Four domesticated strains of Nile tilapia ( Oreochromis niloticus L.) were genetically characterized using 14 microsatellite markers and 64 animals per strain. Two strains, Chitralada (AIT) and International Development Research Centers (IDRC) were obtained from the AIT institute, Bangkok, Thailand. The GIFT strain (5th generation) came from NAGRI, Thailand, and the GÖTT strain was supplied by the University of Göttingen, Germany. The average numbers of alleles per marker were 5.0 (GÖTT), 5.4 (AIT), 5.6 (IDRC) and 7.5 (GIFT). Private alleles were found at all markers with the exception of two. No fixation of alleles was found at any marker. Population differentiation, FST, was 0.178 (great genetic differentiation) and confirmed grouping of the animals in strains. The expected level of heterozygosity ranged from 0.624 to 0.711, but the observed level of heterozygosity significantly deviated from the expected level in three strains. This was probably because of small population size. Moderate to great genetic differentiation was found between strains. A phylogenetic tree reflected the strains known histories. Application of the Weitzman approach showed that all strains have added value for the total genetic diversity and thus should be retained. [ABSTRACT FROM AUTHOR]

Objectives: Microlaryngeal surgeries require unique considerations for airway management to facilitate patient safety and adequate surgical exposure. Small-diameter endotracheal tubes (ETTs) are widely used but have raised concerns regarding patient safety, including questions about the potential for barotrauma, effective ventilation, and adequate oxygenation. We hypothesize that small ETTs will prove to be safe in a variety of cases., Methods: We conducted a case series analyzing the safety of 5.0 ETTs in microlaryngeal surgeries at Washington University School of Medicine from November 2020 to November 2023. Outcome measures included intraoperative desaturations (SpO 2  < 90% for >2 min), high peak inspiratory pressures (PIPs) (>40 cm H 2 O), and prolonged extubation times (>15 min). Univariate regression models were used to analyze associations of sociodemographic and clinical variables with these outcome measures., Results: This study included 76 small-ETT microlaryngeal surgeries. There were 5 instances of desaturations, no reported incidents of barotrauma, and no cases in which intraoperative tube exchange was required due to issues with oxygenation or ventilation. Median PIP was 38 cm H 2 O, with a range of 17-78 cm H 2 O. 46% of patients had a PIP above 40 cm H 2 O. There were prolonged extubation times in 14% of procedures. No association was shown between sociodemographic and clinical variables with risk of desaturations, high PIPs, or prolonged extubation times., Conclusion: Our study suggests that 5.0 ETTs are safe for microlaryngeal surgery in a variety of patients. Otolaryngologists and anesthesiologists should consider this information when choosing between the multiple available options for airway management during microlaryngeal surgery., Level of Evidence: Level 4 Laryngoscope, 2024., (© 2024 The American Laryngological, Rhinological and Otological Society, Inc.)