RESUMO
Honey bees are an important agricultural species; however, relatively little work has been done to improve artificial reproductive technologies for this animal. The collection and distribution of germplasm for breeding and conservation is critical for improving managed honey bee populations and conserving threatened subspecies. The most efficient method of controlling breeding in honey bees is by artificial insemination. The collection of semen for insemination requires the use of antibiotics, which is especially critical if semen is to be stored for any length of time. The introduction of antibiotics is normally done through a balanced salt solution. In this study we compare, at two temperatures, the storage of undiluted semen in antibiotic-gel-coated capillary tubes with storage of semen diluted in a balanced salt solution containing antibiotics. Live-dead cell staining and artificial insemination of honey bee queens were performed at 45, 99 and 439 days after collection of the semen. In every case the antibiotic-gel-coated tube storage method at 14°C produced a higher percentage of fertilised offspring. This study demonstrates the longest period of time spermatozoa have been stored above freezing while maintaining fertilisation capacity.
Assuntos
Cruzamento/métodos , Congelamento , Inseminação Artificial/veterinária , Preservação do Sêmen/veterinária , Espermatozoides , Animais , Abelhas , Inseminação Artificial/métodos , Masculino , Preservação do Sêmen/instrumentação , Preservação do Sêmen/métodosRESUMO
Slush nitrogen (SN) is used to avoid the Leidenfrost effect, which is problematic when using liquid nitrogen (LN). Slush nitrogen's usefulness has been demonstrated by its requirement for the successful cryopreservation of insect embryos. To convert LN to SN, typically, the pressure above a Dewar of LN is reduced, using a vacuum pump in a sealed system until conversion occurs. It has been observed that LN from a fresh tank will readily produce SN; however, repeated use of the same LN results in the inability to form SN in subsequent trials. The current experiments were designed to identify the cause of this phenomenon. The hypothesis is that gaseous oxygen from the surrounding, ambient air condenses and mixes with the LN to form a mixture with a lower freezing point and; therefore, prevents the formation of SN. The hypothesis was tested and found to be true.
Assuntos
Criopreservação , Gases/química , Nitrogênio/química , Oxigênio/química , Ar/análise , Criopreservação/métodos , Temperatura de TransiçãoRESUMO
Much of the world's food production is dependent on honey bees for pollination, and expanding food production will further increase the demand for managed pollination services. Apiculturists outside the native range of the honey bee, in the Americas, Australia and eastern Asia, have used only a few of the 27 described subspecies of honey bees (Apis mellifera) for beekeeping purposes. Within the endemic ranges of a particular subspecies, hybridisation can threaten native subspecies when local beekeepers import and propagate non-native honey bees. For many threatened species, cryopreserved germplasm can provide a resource for the preservation of diversity and recovery of endangered populations. However, although instrumental insemination of queen honey bees is well established, the absence of an effective means to cryopreserve honey bee semen has limited the success of efforts to preserve genetic diversity within the species or to develop repositories of honey bee germplasm for breeding purposes. Herein we report that some queens inseminated with cryopreserved semen were capable of producing a substantial number of fertilised offspring. These diploid female larvae were used to produce two additional sequential generations of new queens, which were then back-crossed to the same stock of frozen semen. Our results demonstrate the ability to produce queens using cryopreserved honey bee spermatozoa and the potential for the establishment of a honey bee genetic repository.
Assuntos
Abelhas/genética , Cruzamento/métodos , Preservação do Sêmen/veterinária , Animais , Criopreservação/métodos , Criopreservação/veterinária , Espécies em Perigo de Extinção , Feminino , Variação Genética , Endogamia , Inseminação Artificial/veterinária , Masculino , Preservação do Sêmen/métodos , Motilidade dos EspermatozoidesRESUMO
BACKGROUND: Trauma registries may contain records without a codable trauma diagnosis, creating a "data gap" that multiplies the number of invalid registry data fields. We designed an investigation intended to determine the incidence of registry records with noncodable trauma diagnoses, characterize those records, and determine the reasons for inadequate diagnosis data. METHODS: We used a retrospective cohort design. A query of trauma registry records spanning a 5-year period yielded 129 records with no injury severity score. Each patient's medical record was reviewed, sources of diagnostic information were noted, and diagnoses were categorized. RESULTS: In 57% of cases, we found documentation that the patient had sustained an injury, but the injury was inadequately documented in the discharge summary. In 19% of cases, although the registry record was valid, the diagnosis was not codable as trauma. In 17% of cases, clinical documentation was adequate, but the diagnosis was inadequately recorded in the trauma registry. In 13% of cases, no traumatic injury was sustained, although the registry record was valid. In 2% of cases, the trauma registry record itself was invalid. In 1% of cases, a coding error occurred. Particularly prominent among records with inadequate discharge documentation were cases of head and spine injury for which there was no radiographic evidence. CONCLUSIONS: The incidence of records with noncodable diagnoses might best be reduced through improved physician documentation, revision of trauma registry inclusion criteria, increased attention by trauma registrars to key sources of documentation, and direct communication with the attending physician when necessary.