Proteins Associated With the Early Intrauterine Equine Conceptus

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 F_2α (PGF_2α). 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 PGF_2α. 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 PGF_2α 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.     

Prevalence of the AMHR2 mutation in Miniature Schnauzers and genetic investigation of a Belgian Malinois with persistent Müllerian duct syndrome

Persistent Müllerian duct syndrome (PMDS) is a sex‐limited disorder in which males develop portions of the female reproductive tract. Important consequences of PMDS are cryptorchidism and its sequelae of infertility and increased risk of testicular cancer. Anti‐Müllerian hormone (AMH) and its receptor (AMHR2) induce the regression of the Müllerian ducts in male embryos. In Miniature Schnauzer dogs, the genetic basis has been identified as an autosomal recessive nonsense mutation in AMHR2, but the allele frequency of the mutation is unknown. Thus, the primary objective of this study was to estimate the prevalence of the AMHR2 mutation in North American Miniature Schnauzers, in order to ascertain the value of genetic testing in this breed. An additional objective was to determine whether mutations in AMH or AMHR2 were responsible for PMDS in a Belgian Malinois; this would aid development of a genetic test for the Belgian Malinois breed. Genomic DNA from 216 Miniature Schnauzers (including one known PMDS case) was genotyped for the AMHR2 mutation, and DNA from a single PMDS‐affected Belgian Malinois was sequenced for all coding exons of AMH and AMHR2. The Miniature Schnauzer cohort had an AMHR2 mutation allele frequency of 0.16 and a carrier genotypic frequency of 0.27. The genetic basis for PMDS in the Belgian Malinois was not determined, as no coding or splicing mutations were identified in either AMH or AMHR2. These findings support a benefit to AMHR2 mutation testing Miniature Schnauzers used for breeding or with cryptorchidism.     

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.     

Bovine abortion associated with Leptospira interrogans serovar hardjo infection

During 1981, 265 bovine abortions were investigated by serological and histological methods for evidence of leptospiral infection. Leptospires were demonstrated in the tissues of 10 foetuses by a Levaditi silver impregnation technique. Serological testing of maternal sera indicated that Leptospira interrogans serovar hardjo was associated with 5 of the abortions while the remaining 5 were due to L. interrogans serovar pomona infection. In cases of abortion associated with L. interrogans serovar hardjo leptospires were readily demonstrated in foetal liver, kidney, intestine and heart. They were demonstrated less often in lung and placenta and could not be found in foetal brain. Autolysis did not appear to interfere with the demonstration of leptospires by silver impregnation. No lesions attributable to leptospiral infection were seen in placentas but mild interstitial nephritis was found in some of the foetuses. Fourteen other cows had serological evidence of recent leptospiral infection but leptospires were not detected in foetal tissues. Histological examination of silver impregnated foetal tissues in combination with the microscopic agglutination test was shown to be an effective method for diagnosing abortion associated with L. interrogans serovar hardjo in cattle.     

Distribution of thiobacillus ferrooxidans and leptospirillum ferrooxidans: implications for generation of acid mine drainage

Although Thiobacillus ferrooxidans and Leptospirillum ferrooxidans are widely considered to be the microorganisms that control the rate of generation of acid mine drainage, little is known about their natural distribution and abundance. Fluorescence in situ hybridization studies showed that at Iron Mountain, California, T. ferrooxidans occurs in peripheral slime-based communities (at pH over 1.3 and temperature under 30 degreesC) but not in important subsurface acid-forming environments (pH 0.3 to 0.7, temperature 30 degrees to 50 degreesC). Leptospirillum ferrooxidans is abundant in slimes and as a planktonic organism in environments with lower pH. Thiobacillus ferrooxidans affects the precipitation of ferric iron solids but plays a limited role in acid generation, and neither species controls direct catalysis at low pH at this site.     

Prevalence and characterisation of wounds in sheep attributed to attacks by kea (Nestor notabilis) on high country farms in New Zealand

ABSTRACT

Aims: To characterise and classify wounds in sheep suspected to have been caused by attacks by kea (Nestor notabilis) (kea strike), and to report the prevalence of these wounds on five high country farms in the South Island of New Zealand.

Methods: Data were collected from farms between 28 August 2012 and 20 September 2013. Sheep were examined opportunistically immediately after shearing for signs of wounds caused by kea. The age and sex of sheep were also recorded. Wounds were measured and characterised as recent, healing, or healed, and the estimated true prevalence was calculated for each farm.

Results: Injuries consistent with kea strike wounds were identified in 70/13,978 (0.5%) sheep examined. The estimated true prevalence varied between farms, from 0 (95% CI?=?0–0.16) to 1.25 (95% CI?=?0.97–1.61)%. Of the 76 wounds identified, 61 (80%) were located in the lumbar region, and 74 (97%) consisted of full-thickness ulceration of the skin, one showed evidence of injury to muscle and one to bone. The median length of the 63 wounds measured was 6 (min 1, max?23.5) cm, and 10/63 (13%) were categorised as recently healed, 47/63 (62%) as healing, and 17/63 (22%) as recent wounds.

Conclusions: The results of this study show that kea strike on sheep was occurring at a low prevalence on the high country farms surveyed. The wounds identified were survivable, but the welfare impact of kea strike on sheep should be considered in balance with the conservation status of kea. There was clear variation in the prevalence of wounds attributed to kea strike between the farms but we were not able to identify the risk factors contributing to these differences. Future studies of kea strike should examine variables such as altitude, local kea density and distribution, and differences in kea strike management and husbandry practices, and should include high country farms without a history of kea strike.     

Implications of intensification of pastoral animal production on animal welfare

The intensification of pastoral animal production results from several major developments including increased forage production and utilisation, diet supplementation, breeding animals to increase milk, meat or wool production, and changes in management. The impact of increased intensification on welfare will differ across species and systems. More intensive-grazing systems and the feeding of novel forages will underpin all moves to intensification. More intensive grazing generally reduces opportunities for shade and shelter. Improved nutrition will generally benefit welfare but competition for available feed may cause increased social pressure. Increased flock and herd size will be associated with a reduction in the human:animal ratio and less time to observe individual animals. Remote monitoring of activity and health might counter this impact.

Intensification of dairy production will result in larger herds, more year-round milking, robotic milking, use of housing and yards year round, and total mixed-ration feeding. Larger herds mean longer distances to walk to and from the dairy shed, and more lameness and less time to spend on self-maintenance activities such as grooming. Holding and feeding dairy cows on yards will cause an increase in lameness and mastitis and perhaps an increase in agonistic behaviour but will reduce time spent walking. Intensification of sheep production will involve increased flock size, increased fecundity, breeding from hoggets, and breeding ewes all year round. Housing during lambing might be considered appropriate, as would feeding to lift milk yields. Increased fecundity with an increase in triplets will increase lamb mortality rates, but housing ewes, when managed well, will result in reduced lamb mortality. Intensification of lamb finishing will be by improved nutrition. Intensification of beef production will include more breeding of heifers at 15 months, and more problems with dystocia.

Intensification of pastoral production will have positive and negative effects on animal welfare. The balance will be determined by the quality of management and stockmanship, and the pressure on businesses to be profitable.