Ovine rumen papillae biopsy via oral endoscopy; a rapid and repeatable method for serial sampling

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.     

Effect of replacing barley with rice bran in finishing diet on productive performance and carcass characteristics of Afshari lambs

Thirty-five male Afshari lambs (3.5 months old), with an average weight of 35 kg were randomly assigned to one of five experimental treatments relating to optimal replacement level of rice bran in lamb finishing diets. The lambs were fed a milled concentrate (3 mm screen) diet supplemented with 15% (DM basis) chopped (5 cm length) lucerne hay and chopped (5 cm length) maize silage or wet (80% moisture) sugar beet pulp. Barley grain in the lambs’ diets was replaced by rice bran at either 0, 15, 30, 45 or 60% of the concentrate mixture on a dry matter basis. Results show that lambs fed 45 and 60% rice bran treatments weighed significantly less than those fed with 15 and 30% and control group (P < 0.05). Average daily gain in lambs fed with concentrate mixtures containing 45 and 60% rice bran were 33 and 47% lower than control, respectively (P < 0.05). Lambs that received diets containing 45 and 60% rice bran, had lower feed intake (P < 0.05) than other groups. Using rice bran in the finishing diet had no significant effect on dressing percentage, tail percentage, abdominal fat and visceral organ weights. These results suggest that barley can be replaced with rice bran up to 30% in the finishing diets of lambs without any adverse effect on lamb performance.     

Geographic variation in marine turtle fibropapillomatosis.

We document three examples of fibropapillomatosis by histology, quantitative polymerase chain reaction (qPCR), and sequence analysis from three different geographic areas. Tumors compatible in morphology with fibropapillomatosis were seen in green turtles from Puerto Rico and San Diego (California) and in a hybrid loggerhead/ hawksbill turtle from Florida Bay (Florida). Tumors were confirmed as fibropapillomas on histology, although severity of disease varied between cases. Polymerase chain reaction (PCR) analyses revealed infection with the fibropapilloma-associated turtle herpesvirus (FPTHV) in all cases, albeit at highly variable copy numbers per cell. Alignment of a portion of the polymerase gene from each fibropapilloma-associated turtle herpesvirus isolate demonstrated geographic variation in sequence. These cases illustrate geographic variation in both the pathology and the virology of fibropapillomatosis.     

Serum and skin IgA concentrations in normal and atopic dogs

Objective To compare serum and skin surface IgA concentrations from atopic and normal dogs.
Procedure IgA concentrations in sera and skin washings of 20 clinically normal dogs that had no history of pruritus or skin disease were compared to those obtained in 20 dogs with a diagnosis of atopy determined by history, clinical examination and positive intradermal skin test.
Results There was no significant difference in the mean serum IgA concentration in normal dogs (252 ± 187 mg/L) versus atopic animals (314 ± 327). When skin washings from all sites in both groups were compared, atopic dogs had significantly greater concentrations of IgA in their skin washings than normal dogs as evaluated by an enzyme-linked immunoassay (P < 0.001). However, there was no significant difference between the individual sites of the skin washings of atopic and normal dogs.
Conclusion IgA concentrations of skin washings in atopic dogs were greater than in normal dogs. Further investigations need to determine if the greater concentrations were caused by nonspecific inflammation or by secretion of allergen-specific IgA onto the skin surface.