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Abstract Recombinant adeno-associated viral (AAV) vectors are a promising gene delivery platform, but ongoing clinical trials continue to highlight a relatively narrow therapeutic window. Effective clinical translation is confounded, at least in part, by differences in AAV biology across animal species. Here, we tackle this challenge by sequentially evolving AAV capsid libraries in mice, pigs and macaques. We discover a highly potent, cross-species compatible variant (AAV.cc47) that shows improved attributes benchmarked against AAV serotype 9 as evidenced by robust reporter and therapeutic gene expression, Cre recombination and CRISPR genome editing in normal and diseased mouse models. Enhanced transduction efficiency of AAV.cc47 vectors is further corroborated in macaques and pigs, providing a strong rationale for potential clinical translation into human gene therapies. We envision that ccAAV vectors may not only improve predictive modeling in preclinical studies, but also clinical translatability by broadening the therapeutic window of AAV based gene therapies.

The study provided an empirical evidence on the use of improved goat production technologies among rural farmers in Abia State, Nigeria. The specific objectives of the study were to describe the socioeconomic characteristics of the respondent, ascertain the extent of use of improved goat production technologies, determine factors influencing use of improved goat production technologies and identify the constraint to access and use of improved goat production technologies in the study area. A multi-stage random sampling technique was adopted in selecting the sample size 120 respondents. Data for the study were collected through the use of questionnaire. The data collected for the study were analysed with both descriptive and inferential statistics. The result on awareness of improved goat production technologies revealed that, the respondents were aware of dipping (100%), deworming (99.2%) fostering of kids (93.3%), colostrum feeding (71.7%) among others. The result on extent of use of improved goat production technologies, revealed that the respondents highly used most of improved goat production technologies as affirmed with the grand mean of = 3.20. On constraint to use of improved goat production technologies, all the respondents 100% agreed that lack of access to credit was a constraint to use, 100% agrees on lack of credibility from source of technological information, 99.2% agreed that they were afraid of taking risk, 93.3% agreed on difficulty in technology application among others. The OLS regression estimates of the influence of socioeconomic characteristics the respondents on the use of improved goat production technologies in the study area, revealed that age at 10%, education at 1%, household size at 1%, farming experience at 1%, farm size at 1%, income at 1% and access to credit at 5% were the determinants of use of improved goat production technologies in the study area and the null hypotheses rejected. In conclusion, greater use of available improved technologies will promote productivity, and therefore there is need for proper sensitization and awareness by relevant agencies. Again credit should be made available to farmers by relevant governmental and non- governmental agencies to increase the level of use of available improved technologies.

The study assessed s soil conservation and water – resources management techniques among small- scale rice farmers in Ebonyi State. A sample of 130 respondents generated via multi- stage, purposive and simple random methods were used. Data were generated through questionnaire and interview schedule and analysed using percentage and mean. Results, showed the indigenous methods for soil and water- resources management used by the rice farmers to include: construction of basin and flow walls (= 92.3%), construction of dikes (= 84.6%), ration- harvesting (= 73%), compost- manuring (= 69%) and were ranked from 1st position to 5th position .Other indigenous methods used include: use of IPM (= 65.4%), shifting cultivation and planting of trees (= 61.5%) and crop rotation(= 57.7%) respectively were ranked from 7th position to 10th position respectively. Mixed cropping (= 50.0%) ranked 11th. Results on level of use of Agronomical Best Environmental Management Practices (ABEMPs) through physical measures indicated that construction of bund- lines (= 3.23) and farm- drainage (= 3.00) were at high level of use, while levelling (= 2.96), dikes (= 2.77), stone- lines (= 2.39), terracing (= 2.15) were at moderate level of use and plastic mulching (= 1.85) was at low level of use. Equally, for biological measures mixed- cropping (= 3.08) was at high level of use, while crop- rotation (= 2.80), planting of trees (= 2.62) and fallow- cover (= 2.23) were at moderate level of use and incorporation of residues (= 1.92) was at low level of use. On the Best Agronomic Practice measures, results showed conservation tillage and liming (= 3.00) were respectively at high level of use, while mount- making / ridging (= 2.92), application of compost manure (= 2.62), use of IPM (2.62) and application of cow dung and poultry droppings (= 2.50) were at moderate level of use, while irrigation (= 1.77) and zero tillage (= 1.23) were at low level of use respectively. The indigenous and ABEMPs methods are geared towards stable renewable resource use through sustainable (soil and water- resources) management techniques. There should be enhanced farmer–scientist research collaboration to develop soil and water- resource management techniques for more sustainable for rice production in the study area.

The study measured the variables: socio- economic characteristics of the respondents, their non- farm preferred enterprises, perceived training needs, and challenges encountered by the respondents in the study area. The sample size was 120 respondents generated via multi – stage sampling procedure. Data were generated using questionnaire and analyzed using descriptive statistics such as frequency, percentage, mean, ranks, pooled mean and standard deviation. Results showed 30 years as the mean age of the respondents, 83.3 % were literates, 70.8 % were married and earned a mean monthly income of ₦27,250.00. Eateries (= 3.17), farm – gate trading (= 3.08), hired labour workers (=3.04) and general merchandise (=3.00) were identified as non- farm enterprises in the study area. Record – keeping ( = 4.17), access to capital (=4.08), self – confidence ( = 3.83), decision – making (= 3.75), resource allocation (= 3.71)and market information ( =3.50), were identified as preferred training needs by the respondents. High social barrier (100%), lack of start- up fund (95.83 %), lack of credit facilities ( 91.67 %), limited access to business training (79.17 %) were identified as challenges confronting rural women entrepreneurs. The study concludes that the rural women entrepreneurs preferred to be trained on record keeping and how to access capital and therefore recommends that government and other stakeholders should encourage and empower the respondents by mounting entrepreneurial training in the areas of identified training needs.

Molecular biology has enabled the identification of the mechanisms whereby inactive myostatin increases skeletal muscle growth in double-muscled (DM) animals. Myostatin is a secreted growth differentiation factor belonging to the transforming growth factor-β superfamily. Mutations make the myostatin gene inactive, resulting in muscle hypertrophy. The relationship between the different characteristics of DM cattle are defined with possible consequences for livestock husbandry. The extremely high carcass yield of DM animals coincides with a reduction in the size of most vital organs. As a consequence, DM animals may be more susceptible to respiratory disease, urolithiasis, lameness, nutritional stress, heat stress and dystocia, resulting in a lower robustness. Their feed intake capacity is reduced, necessitating a diet with a greater nutrient density. The modified myofiber type is responsible for a lower capillary density, and it induces a more glycolytic metabolism. There are associated changes for the living animal and post-mortem metabolism alterations, requiring appropriate slaughter conditions to maintain a high meat quality. Intramuscular fat content is low, and it is characterized by more unsaturated fatty acids, providing healthier meat for the consumer. It may not always be easy to find a balance between the different disciplines underlying the livestock husbandry of DM animals to realize a good performance and health and meat quality.