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Background: Meat goat breeding programs should prioritize the identification and selection of genetically superior animals for traits related to meat quality and carcass yield in order to increase the value of the final product. Objective: To estimate (co)variance components and genetic parameters for ultrasound-measured carcass traits, body size and body weight in AngloNubian breed goats raised in the Mid-North region of Brazil. Methods: (Co)variance components and genetic parameters were estimated using the single and two-trait animal model analyses via Bayesian inference for loin eye dimensions (area, length, and depth), sternal fat thickness, rump height, chest circumference and depth, leg perimeter, and body weight. Results: Heritability estimates were higher when two-trait analyses were used. This finding implies that it is possible to recover part of the additive genetic variance included in the residual variance due to the correlation between traits. Genetic correlations between carcass and body size traits showed different magnitudes. On the other hand, genetic correlations between the traits related to muscularity showed high magnitudes. Conclusions: Body weight was not a good indicator of muscularity; therefore, it is not recommended as a criterion for indirect selection to improve carcass traits of Anglo-Nubian goats. Leg perimeter and chest circumference may be important to construct selection indexes in meat goat breeding programs.

Summary Background: Nellore cows are well adapted to tropical conditions, and they have good maternal ability as well as long and prolific reproductive life. Objective: to estimate (co)variances and genetic parameters for calving interval (CI), age at first calving (AFC), gestation length (GL), and days open (DO) in Nellore cows. Methods: covariance components and genetic parameters were estimated using multi-trait Bayesian procedures. Results: three traits had low but statistically significant heritabilities, averaging 0.05, 0.10, and 0.04 for CI, GL, and DO, respectively, whereas age at first calving had a higher heritability (0.36). The permanent environmental effects for CI, GL, and DO were also low, averaging 0.08, 0.07, and 0.15, respectively. The genetic correlations between AFC and CI, AFC and GL, AFC and DO, GL and CI, CI and DO, GL and DO were 0.20, 0.12, 0.11, 0.02, 0.92, and -0.21, respectively. Selection for shorter CI would contribute towards decreasing DO. However, selection for decreased GL could result in a greater number of DO. Despite the favorable genetic correlations, the direct selection responses for these traits would be low. Conclusion: reproductive traits are strongly influenced by environmental effects. Changes in management and environmental factors could rapidly improve reproductive performance of Polled Nellore herds. Genetic selection for these traits should produce a much slower but permanent response. Resumo Antecedentes: vacas da raça Nelore são bem adaptadas às condições tropicais e apresentam boa habilidade materna, bem como elevada longevidade e prolificidade. Objetivos: avaliar a estimativa de (co)variâncias e parâmetros genéticos para o intervalo de partos (IEP), idade ao primeiro parto (IPP), duração da gestação (DG) e período de serviço (PS) em vacas da raça Nelore. Métodos: componentes de covariância e parâmetros genéticos foram estimados por meio de procedimentos bayesianos multicaracterísticos. Resultados: três características apresentaram baixa herdabilidade, com média de 0,05, 0,10 e 0,04 para IEP, DG e PS, respectivamente, já a idade ao primeiro parto apresentou maior herdabilidade (0,36). Os efeitos de permanentes associados á IEP, DG e PS também apresentaram baixas estimativas, 0,08, 0,07 e 0,15, respectivamente. As estimativas de correlação genética entre IPP e IEP, IPP e DG, IPP e PS, IEP e DG, IEP e PS, e DG e PS foram de 0,20, 0,12, 0,11, 0,02, 0,92 e -0,21, respectivamente. A seleção para redução do IEP poderá contribuir para uma significativa redução PS. No entanto, a seleção para redução do DG poderá resultar em aumento do PS. Apesar das favoráveis estimativas de correlações genéticas, a resposta de seleção direta para essas características seria baixa. Conclusão: as características reprodutivas são fortemente afetadas por efeitos ambientais. Assim, as mudanças nas condições de manejo e ambientais resultariam em uma melhora expressiva dessas características, enquanto que a seleção genética produziria melhorias mais lentas, porém permanentes. Resumen Antecedentes: las vacas Nelore se adaptan bien a las condiciones tropicales, y tienen buena habilidad materna, así como larga y prolífica vida reproductiva. Objetivo: evaluar la estimación de las (co)varianzas y los parámetros genéticos para el intervalo entre partos (CI), la edad al primer parto (AFC), duración de la gestación (GL) y el período de servicio (DO) en vacas Nelore. Métodos: los componentes de covarianza y los parámetros genéticos fueron estimados por procedimientos multivariados Bayesianos. Resultados: tres características, CI, GL y DO presentaron bajos promedios de heredabilidad, promediando 0,05, 0,10 y 0,04, respectivamente, mientras que la edad al primer parto presentó una heredabilidad más alta (0,36). Los efectos ambientales permanentes del CI, GL y DO también resultaron con estimaciones bajas, con promedios de 0,08, 0,07 y 0,15, respectivamente. Las estimaciones de las correlaciones genéticas entre AFC y CI, AFC y GL, AFC y DO, GL y CI, CI y DO, GL y DO fueron 0,20, 0,12, 0,11, 0,02, 0,92 y 0,21, respectivamente. La selección para un CI reducido puede contribuir a una reducción de los DO. Sin embargo, la reducción de la GL puede dar lugar a un mayor DO. A pesar de las favorables estimaciones de la correlación genética, la respuesta a la selección directa de estos rasgos sería baja. Conclusión: las características reproductivas se ven fuertemente afectadas por efectos ambientales. Así, los cambios en la gestión y las condiciones ambientales dan lugar a una mejora rápida de estas características, mientras que la selección genética produce cambios más lentos pero permanentes.

Muga silkworm is endemic to Assam and adjoining areas in North-Eastern India, and naturally produces golden silk. From time immemorial, many ethnic and tribal groups have produced muga silk. Muga silkworms are mostly wild unlike the mulberry silkworm, which is completely domesticated. The muga silkworm is a single species with little genetic variation among populations, survives harsh climatic conditions and is subject to various diseases, pests and predators. Due to the high incidence of disease and natural enemies, and variations in climatic conditions, the production of muga silk has recently declined dramatically. In order to improve the productivity of this silkworm it is important to have a better knowledge of both its host plants and biology. Lack of knowledge of its genetics and host plants is a major bottleneck. This paper reviews various aspects of muga silkworm culture, including the availability of different populations, and methods used to select for improvement in survival, cocoon yield, disease resistance, conservation and egg production.

The use of captive breeding in species recovery has grown enormously in recent years, but without a concurrent growth in appreciation of its limitations. Problems with (1) establishing self-sufficient captive populations, (2) poor success in reintroductions, (3) high costs, (4) domestication, (5) preemption of other recovery techniques, (6) disease outbreaks, and (7) maintaining administrative continuity have all been significant. The technique has often been invoked prematurely and should not normally be employed before a careful field evaluation of costs and benefits of all conservation alternatives has been accomplished and a determination made that captive breeding is essential for species survival. Merely demonstrating that a species' population is declining or has fallen below what may be a minimum viable size does not constitute enough analysis to justify captive breeding as a recovery measure. Captive breeding should be viewed as a last resort in species recovery and not a prophylactic or long-term solution because of the inexorable genetic and phenotypic changes that occur in captive environments. Captive breeding can play a crucial role in recovery of some species for which effective alternatives are unavailable in the short term. However, it should not displace habitat and ecosystem protection nor should it be invoked in the absence of comprehensive efforts to maintain or restore populations in wild habitats. Zoological institutions with captive breeding programs should operate under carefully defined conditions of disease prevention and genetic/behavioral management. More important, these institutions should help preserve biodiversity through their capacities for public education, professional training, research, and support of in situ conservation efforts.

El objetivo de esta investigación fue determinar la tendencia genética y fenotípica de la producción de leche (PL) de vacas Holstein de un establo del valle de Huaura, Perú. Se evaluaron 2.590 hembras (vacas y terneras) para el cálculo de los valores genéticos estimados (VGE) y 2.862 lactaciones estandarizadas a 305 días y dos ordeños diarios, del primer al quinto parto de 1.892 vacas del periodo 1999-2017, mediante un modelo animal de medidas repetidas. Con el software ASReml, se estimó una heredabilidad (h2) de 0,16 (error estándar 0,03) y una repetibilidad (r) de 0,28 (0,025). Las tendencias se estimaron mediante regresión lineal usando el paquete estadístico SAS v.9.4. Los VGE para la PL de las vacas y terneras tienen una media de +200,9 (16,1) kg y +148,7 (9,7) kg, respectivamente, con más del 70 % de valores positivos. La tendencia genética para PL de las hembras fue -2,4 (2,1) kg/año. Se estimó una tendencia fenotípica para PL de +294,3 (24,9) kg/año. Se concluye que la tendencia fenotípica es favorable debido a mejoras en aspectos no genéticos, ya que la h2 indica que la PL está influenciada principalmente por el ambiente y, en menor medida, por la varianza genética aditiva del carácter. La tendencia genética para la PL de hembras fue negativa. Sin embargo, los VGE para PL de las hembras vivas sugieren que a futuro, el establo puede incrementar la tendencia genética para PL.

A central issue in evolutionary biology is the extent to which complex social organization is under genetic control. We have found that a single genomic element marked by the protein-encoding gene Gp-9 is responsible for the existence of two distinct forms of social organization in the fire ant Solenopsis invicta. This genetic factor influences the reproductive phenotypes and behavioral strategies of queens and determines whether workers tolerate a single fertile queen or multiple queens per colony. Furthermore, this factor affects worker tolerance of queens with alternate genotypes, thus explaining the dramatic differences in Gp-9 allele frequencies observed between the two social forms in the wild. These findings reveal how a single genetic factor can have major effects on complex social behavior and influence the nature of social organization

Cyprinus carpio introduced about sixty years ago for aquaculture has now been found to invade into the Ganga River (India), the largest river of the country contributing significantly to the fishery. The abundance index of C. carpio ranged from 12.2% to 45.5 % in 250 km long river stretch of the Ganga River flowing along Kanpur to Varanasi in the state of Uttar Pradesh. The gut content analysis revealed the presence of Eichhornia (9.8%), Pistia (11.6%), Nymphaea (8.5%), annelids worms (7.8%), algae (20.2%), mud and detritus (14.8%). The calculated diet breadth ranged from 0.82% to 0.91%; food richness ranged from 12 to 16, and the gut repletion index (GRI%) was 100% at different sampling sites. Presence of spent, ripe, and mature females was recorded. Abundance of exotic fish primarily C. carpio and Oreochromis niloticus in the fishery of the Ganga River was observed. The dominant catch of exotic fishes negatively impacted on the important indigenous fishes particularly Indian major carps (Catla catla,Labeo rohita,and Cirrhinus mrigala)

Los polimorfismos en el gen dopamina b-hidroxilasa (DBH) se asocian con el temperamento en los bovinos. En 16 animales de la raza criolla colombiana Blanco Orejinegro (BON), 20 Brahman (BRA) y 16 de Ganado de lidia (GLI), se evaluaron los polimorfismos del exón xii del gen DBH mediante secuenciación. Se encontraron 13 haplotipos, 6 en BON, 9 en BRA y 2 en GLI. El haplotipo H2 fue el más frecuente (0,615) y se encontró en las tres razas, mientras los haplotipos H6 y H9 fueron compartidos entre BON-BRA y BRA-GLI, respectivamente. La mayor diversidad genética (DG: 0,915 ± 0,04) y nucleotídica (DN: 0,011 ± 0,006) se encontró en la raza BRA, seguida por BON (DG: 0,700 ± 0,12; DN: 0,008 ± 0,004) y GLI (DG: 0,350 ± 0,14; DN: 0,0011 ± 0,001). Si bien el test de D-Tajima fue mayor que cero, no fue significativo (P > 0,05) en BON y BRA, pero en la raza GLI presentó un valor de −1,92 (P < 0,05). El análisis de varianza molecular mostró una variación entre las razas de 23,9% y una estructura poblacional (FST) de 0,23 (P < 0,001). Los mayores valores del coeficiente de coancestría se presentaron entre GLI y BRA (0,52) y entre GLI y BON (0,22). Se concluye que la raza GLI tiene baja diversidad en el gen DBH en comparación con las razas BON y BRA, que hay efectos de la selección neutral  en BON y BRA mientras que, en la raza GLI se evidencia un barrido selectivo reciente y no a favor del temperamento.

The effect of non-random mating on genetic response was compared for populations with discrete generations. Mating followed a selection step where the average coancestry of selected animals was constrained, while genetic response was maximised. Minimum coancestry (MC), Minimum coancestry with a maximum of one offspring per mating pair (MC1) and Minimum variance of the relationships of offspring (MVRO) mating schemes resulted in a delay in inbreeding of about two generations compared with Random, Random factorial and Compensatory mating. In these breeding schemes where selection constrains the rate of inbreeding, ΔF, the improved family structure due to non-random mating increased genetic response. For schemes with ΔF constrained to 1.0% and 100 selection candidates, genetic response was 22% higher for the MC1 and MVRO schemes compared with Random mating schemes. For schemes with a less stringent constraint on ΔF or more selection candidates, the superiority of the MC1 and MVRO schemes was smaller (5–6%). In general, MC1 seemed to be the preferred mating method, since it almost always yielded the highest genetic response. MC1 mainly achieved these high genetic responses by avoiding extreme relationships among the offspring, i.e. fullsib offspring are avoided, and by making the contributions of ancestors to offspring more equal by mating least related animals.