AIMS: To explore and validate the utility of rumen endoscopy for collection of rumen papillae for gene expression measurement.
METHODS: Four adult Coopworth ewes were fasted for either 4 or 24 hours. Animals were sedated, placed in a dorsally recumbent position at 45 degrees with the head upright, and an endoscope inserted via a tube inserted into the mouth. Biopsies of rumen papillae were taken from the ventral surface of the rumen atrium under visual guidance. Two biopsies were collected from one of the animals that had been fasted for 4 hours, and three from one of the animals that had been fasted for 24 hours. Video of the rumen atrium and reticulum was also collected. The animals recovered uneventfully. Biopsies were subsequently used for extraction and sequencing of mRNA.
RESULTS: The ventral surface of the rumen atrium was accessible after 4 hours off pasture, but a larger region was accessible after 24 hours of fasting. Sedation allowed access for endoscope use for around 5 to 10 minutes after which increased saliva flow was noted. Rumen papillae biopsies were easily collected, with samples from a variety of sites collected in the ~10 minute time window. High quality RNA was obtained for stranded mRNA sequencing. Of the resulting reads, 69–70% mapped uniquely to version 3.1 of the ovine genome, and 48–49% to a known gene. The rumen mRNA profiles were consistent with a previously reported study.
CONCLUSIONS: This method for obtaining rumenal tissue was found to be rapid and resulted in no apparent short or long term effects on the animal. High quality RNA was successfully extracted and amplified from the rumen papillae biopsies, indicating that this technique could be used for future gene expression studies. The use of rumen endoscopy could be extended to collection of a variety of rumen and reticulum anatomical measurements and deposition and retrieval of small sensors from the rumen. Rumen endoscopy offers an attractive and cost effective approach to repeated rumen biopsies compared with serial slaughter or use of cannulated animals. 相似文献
A critical period of early gestation in the mare involves the immobilization (fixation) of the encapsulated conceptus at around days 16–17. We compared the major proteins in the normal equine embryonic capsule and endometrial secretions around the period of fixation with those from pregnancies in the process of termination induced by administration of an analogue of prostaglandin F2α (PGF2α). Uterocalin and β2-microglobulin (β2M) associated with the embryonic capsule were proteolytically converted to smaller forms during the fixation period. These conversions were similar in conceptuses from control and treated mares. A 17 kDa cationic protein identified as a secretory phospholipase A2 (sPLA2) type IIA was detected bound to normal capsules but increased substantially in response to PGF2α. Two forms of uteroglobin were distinguished by partial amino acid sequences of ∼6 kDa bands in flush fluids from normal pregnant uteri. After administration of PGF2α one immunoreactive form of uteroglobin was preferentially increased. These studies demonstrate that failure of pregnancy in this model is associated with an increase in secretory phospholipase in the capsule and a change in the forms of uteroglobin in the uterine secretions. 相似文献
Background, Aims and Scope Phytoremediation is a promising means for the treatment of heavy metal contamination. Although several species have been identified
as hyperaccumulators, most studies have been conducted with only one metal. Experiments were conducted to investigate the
ability of Helianthus annuus and Thlaspi caerulescens to simultaneously uptake Cd, Cr and Ni.
Materials and Methods The efficiency of plants grown in a sandy-loam soil was investigated. The ability of two EDTA concentrations (0.1 and 0.3
g kg−1) for enhancing the phytoremediation of Cd, Cr and Ni at two different metal concentrations (24.75 mg kg−1 and 90 mg kg−1) was studied.
Results
Thlaspi hyperaccumulated Ni with 0.1 g kg−1 EDTA. When the EDTA dosage was increased to 0.3 g kg−1, Thlaspi was able to hyperaccumulate both Ni and Cr. Since Thlaspi is a low-biomass plant, it was considered insufficient for full-scale applications. Helianthus annuus hyperacummulated Cr (with 0.1 g kg−1 EDTA) and Cd (0.3 g kg−1 EDTA).
Discussion When the contamination was 8.25 mg kg−1 per metal, the total metal uptake was 10–25% (1.35 to 2.12 mg) higher and had the same uptake selectivity (Cr>>Cd>Ni) for
both EDTA levels. It was hypothesized that complexation with EDTA interfered with Ni translocation. For these experiments,
the optimal results were obtained with the H. annuus-0.1 g kg−1 EDTA combination.
Conclusions Although the use of EDTA did increase the amount of metal that could be extracted, care should be taken during in-situ field
applications. Chelators can also increase the amount of metals that are leached past the root zone. Metal leaching and subsequent
migration could lead to ground water contamination as well as lead to new soil contamination.
Recommendations and Perspectives Additional research to identify the optimal EDTA dosage for field applications is warranted. This is necessary to ensure that
the metals do not leach past the root zone.
Identification of a plant that can hyperaccumulate multiple metals is critical for phytoremediation to be a viable remediation
alternative. In addition to being able to hyperaccumulate multiple metals, the optimal plant must be fast growing with sufficient
biomass to sequester the heavy metals. 相似文献
The present study indicates that the development of caprine mammary gland warts seems to depend on several factors--namely, nonpigmented skin, adult age, excessive exposure to sunlight, and contact with a yet undefined infective agent. Three types of goat papillomas are described: mammary, cutaneous, other than mammary, and genital. Warts on animals lacking pigmented skin are more frequent in adult animals that live in areas where there is abundant sunlight. Mammary gland papillomas are the most numerous and occur in different stages: ie, goats with mammary gland papillomas that regress, never to recur, goats with papillomas that regress in the winter and reoccur in summer, goats with persistent papillomas of which some are from the group that had previous winter time regression, and goats that have progression of persistent papilloma to carcinoma. Saanen, Saanen crossbreeds, and goats of other breeds that lack pigmented skin and live in sunbelt areas are at high risk for papillomatosis. An infective agent was not defined even after electron microscopic, immunocytochemical, and DNA-DNA hybridization studies. Yet, there is high probability that an infective agent is involved, because mammary gland papillomas usually occur in the susceptible herd 4 to 6 months after an affected goat is introduced. 相似文献
The sensitivity of the abattoir inspection procedure introduced for Australian export beef in 1976 was compared to a detailed necropsy procedure for the detection of tuberculous lesions in cattle. In a sample of cattle that were reactors to the tuberculin test, abattoir inspection failed to detect an estimated 47% of cattle with lesions. The detailed necropsy examination of cattle with lesions of tuberculosis identified 21 sites of infection compared with 13 to 18 in cattle examined by routine meat inspection procedures. Of the lesions detected during detailed necropsy, 15.9% did not involve the thoracic cavity or the medial retropharyngeal lymph nodes. The failure to detect lesions during abattoir inspection has its greatest significance in an animal with a single lesion. If the 245 cattle found with single lesions during detailed necropsy had been examined by abattoir inspection using the 1976 or the 1986 procedures, 0.8 and 8.9%, respectively, of these animals would not have been detected because the diseased tissues would not have been examined. If meat inspection is to provide an effective means of monitoring the level of bovine tuberculosis during the final stages of eradication, a procedure no less sensitive than that introduced in 1976 should be used. 相似文献
Three cats in one household developed pyogenic subcutaneous abscesses and arthritis over a period of 9.5 months. Despite vigorous surgical and antibiotic treatment, the infections in each of these cats continued to spread locally and hematogenously to involve other joints and subcutaneous sites. Although the infections did not respond to modern broad-spectrum antibiotics, they were susceptible to tetracycline. In spite of a favorable response to tetracycline, all 3 cats were euthanatized. A causative agent could not be identified by microbiologic culture of tissues obtained prior to death and at necropsy, or with special tissue stains. The infection was transmitted experimentally by sc inoculation with cell-free material from one of the naturally infected cats to a specific-pathogen-free cat. A tissue extract from the experimentally infected cat was, in turn, infectious for another specific-pathogen-free cat. The experimentally induced lesion was a rapidly enlarging necrotizing and pyogenic cellulitis and panniculitis, with no demonstrable causative agent by special tissue stains or microbiologic culture. A probable bacterial L-form was visualized in affected tissues of the experimentally infected cats and propagated in special L-form broth. Like the natural disease, infection in experimentally inoculated cats was progressive in nature, but could be treated successfully with tetracycline. 相似文献