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The recent state of cryopreservation techniques for ex-situ gene conservation and breeding purposes in small ruminants: A review
81-87Views:455The viewpoint of the recent cryopreservation techniques (CT) suggests the use of a reduced volume of cryopreservation solution, high concentration of cryoprotectants and ultra-rapid cooling and warming rates help to reduce cryo-injury and maximize the viability of the preserved animal genetic resources (AnGR). The CT had now become widely accepted as one of the best methods of choice for the ex-situ conservation of AnGR due to its high success rate recorded and no-invasive nature as compared to the conventional slow rate freezing (CSRF). Rapid advances and wide acceptability of the use of assisted reproductive technologies (ART’s) particularly artificial insemination (AI) in animal breeding had resulted in a greater loss of a large number of good quality genes in virtually almost all the native breeds of animals across the globe. Small ruminant (SR) animals are not an exception in such present predicaments situation of erosion and dilution of the valuable AnGR among the native breeds. As a result of this, 148 and 16 breeds of sheep and goats respectively have already become extinct in Europe and the Caucasus. In view of the aforementioned situation, the present review aimed at exploring some of the current states of development, roles played and potentials of CT in the conservation of SR genes and genome for the immediate and future breeding purposes for sustainable development. It basically covers; animal genetic resource, the need to conserve AnGR, tools for ex situ in vitro conservation of AnGR and recent developments in breeding and cryopreservation of SR AnGR.
Cryopreservation is playing a pivotal role in ex-situ gene conservation of AnGR. Decline in genetic diversity among SR breed population was high in Europe and the Caucasus. There is therefore, need for improvent on current stringent measures on conservation of AnGR in this region of the world.
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New Integrated Breeding Evaluation Method Used for German Warm-blooded Horses
3-6Views:188In Germany, the new integrated breeding value estimation is based on a multiple-trait animal model, considering simultaneously information from performance test of stallion on station, performance test of mares as well as competition results of sport horses. The objective of this study was to estimated the genetic parameters of the traits used in the integrated breeding evaluation including all German warmblood breeds. The analysed data consisted of 4527, 40670 and six million records for performance tests of stallions, mares and for competition results, respectively. Genetic parameters were estimated with a multivariate BLUP animal model. Heritabilities for traits obtained from stallions tested on station ranged from 0.33 (jumping under rider) to 0.51 (trot) and for the traits from mare performance test from 0.27 (walk) to 0.38 (trot). Genetic correlations between corresponding traits recorded on performance test of stallions and mares ranged from 0.87 (canter) to 0.98 (free jumping). Heritabilities of competition traits from horses (build up for sport) were estimated as 0.12 and 0.11 for dressage and jumping, respectively. The use of all traits for estimation of genetic values of horses is expected to reduce pre-selection and optimal combines all information resources based on the estimated genetic parameters.
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Cannibalism and its importance in Aquaculture: A review
43-54Views:630Intracohort cannibalism may lead to significant losses during the early life stages of farmed fish. The mechanisms driving cannibalism dynamics are common across many fish species and are closely linked to the factors that influence growth variation within a population. This genetically encoded behaviour allows the individual to eliminate competitors in the competition for resources and increases the chances of survival and reproduction. Many fish species display aggression towards individuals of the same species, which can often lead to cannibalistic behavior. This foraging strategy is also present in intensive aquaculture systems, and its economical, ecological and phylogenetic implications have been debated by many researchers. Many fish species can be produced economically in recirculation aquaculture (RAS) systems, but the efficiency of larval and juvenile rearing remains a bottleneck for most species. The success of initial rearing depends on many factors. In addition to genetic factors, the level of cannibalism is mainly influenced by the applied production and feeding technology. Literature suggests that mortality during larval rearing can be as high as 50%, largely due to aggression. In the case of predatory fish species, the presence or absence of certain husbandry conditions can lead to even higher levels of cannibalism, which significantly reduces production yields by causing mortality and secondary injuries, thus further decreasing the survival rate. This review therefore aims to identify and quantify the effects of biotic and abiotic factors that influence cannibalism.
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Phenotypic characterization of Satu Mare Tumbler pigeon breed
31-34Views:233The aim of this study was to determine morphological characteristics of the tumbler pigeon breed of Satu Mare. This pigeon breed was first described in 1932 and was very close to extinction at the end of the 20th century. Data collection was carried out in two stocks having birds from three breeders (Bertalan Juhos, Cosmin Lupu and Werner Hartmann) in Satu Mare. In addition to the breeder, sex and color variety were also evaluated. The performed conformation measurements were statistically compared using multifactor analysis of variance. Lupu’s birds were longer compared to other breeder’s stock, while beak and wing was longer in Juhos’s stock. Thoracic perimeter was smaller whereas queue length was the longer for Juhos’s birds. Cocks’ values were significantly exceeding values of hens, except beak length. Recessive red pigeons had longer body than blue birds. Beak length of recessive yellow pigeons was significantly longer that it was computed for black birds. Wingspan was longer for dun birds than it was estimated for recessive yellow pigeons. These differences show that there is reasonable genetic variability in the breed which is desired in small populations. Due to the variability within the breed, stabilising selection might be favorable, with a special account for avoiding inbreeding.
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Perspectives of the livestock sector in the Philippines: A review
175-188Views:3965The Philippine livestock industry is a vital component in the country's agricultural sector. It contributes around 18.23 percent of the gross output value in agriculture and provides livelihood to many people living in rural areas, signifying its importance with regard to the country’s economy. The constantly increasing demand for animal protein associated with the increase of the world’s population led to the intensification of livestock production, realized through the various initiatives implemented by the government, such as the import of high producing purebreds of various species. This strategy greatly influenced the country's animal genetic resource's diversity and increased food animals' population; however, it impacted the native breeds of food animals. Understanding the characteristics, performance and value of native and exotic breeds is essential to prioritize their livestock industry existence. Thus, this paper aims to characterize various native and exotic breeds of livestock in the Philippines and assess the current conservation of native animals.