Thyroid function and pregnancy status in broodmares

OBJECTIVE: To determine whether thyroid function was associated with pregnancy status in broodmares. DESIGN: Prospective study. ANIMALS: 79 Thoroughbred and Standardbred broodmares between 2 and 22 years old. PROCEDURE: Serum triiodothyronine (T3) concentration was measured before and 2 hours after i.v. administration of thyrotropin releasing hormone (TRH), and serum thyroxine (T4) concentration was measured before and 4 hours after TRH administration. Pregnancy status was monitored by means of transrectal ultrasonography beginning 16 days after ovulation. RESULTS: Baseline T3 and T4 concentrations varied widely. In all mares, serumT3 concentration increased in response to TRH administration. Serum T4 concentration increased in response toTRH administration in all but 2 mares. Pregnancy rate was 76%. Baseline and stimulated serum T3 and T4 concentrations were not significantly different between mares that became pregnant and those that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that decreased thyroid function is uncommon in mares and poor thyroid function is not a common cause of infertility. Thus, the practice of indiscriminately treating broodmares with thyroid hormone to enhance fertility appears questionable at this time.     

Detachment of the ischial tuberosity sows

The clinical and pathological features of five cases of detachment of the ischial tuberosity are described. In two cases, the detachment occurred unilaterally; one was a gilt showing severe lameness which precluded mating and the other was a uniparous sow which showed only slight lameness. Three gilts which were affected bilaterally developed progressive lameness during pregnancy and were unable to stand after farrowing. One of these gilts died and two had to be slaughtered. The diagnostic features of the epiphyseal detachment were shortening of the caudal extremity of the ischium, palpation of the displaced ischial tuberosity and crepitation elicited by pressing the displace tuberosity against the ischium.     

Effect of selection for backfat thickness in swine on fetal skeletal muscle metabolism

At 110 d of gestation, fetuses were removed from sows selected for high (obese) or for low (lean) backfat thickness. The body weights of lean (1,031 +/- 64 g) and obese (864 +/- 55 g) fetuses were not significantly different. Analysis of muscle composition and of in vitro metabolic characteristics was conducted on the biceps femoris muscle. The percentage of dry weight, protein and glycogen was greater in the muscle of obese fetuses than in the muscle of lean fetuses (P less than .01, P less than .05, and P less than .05, respectively). Percentage of muscle triglyceride was similar (P greater than .05) between the two phenotypes. The rate of glucose oxidation to CO2 tended to be greater (P less than .07) and the rate of lactate production was lower (P less than .05) in the muscle from obese fetuses than in the muscle from lean fetuses. The rates of leucine oxidation to CO2 and of palmitate oxidation to CO2 did not differ between phenotypes. The rate of alpha-ketoisocaproate release from the muscle of obese fetuses was greater (P less than .05) than from that of the lean fetuses. The rate of release of alanine and of glutamine plus glutamate did not differ between phenotypes. The rate of esterification of palmitate did not differ between phenotypes. It was concluded that abnormalities in glucose metabolism and in the partitioning of leucine between oxidation and release as the keto acid existed at 110 d of gestation in the muscle of obese fetuses. Any relation between these differences and ultimate differences in carcass composition were not evident.     

Intranasal vaccination of rabbits with Pasteurella multocida A:3 outer membranes that express iron-regulated proteins

OBJECTIVE: To determine efficacy of intranasal vaccination of rabbits with Pasteurella multocida A:3 outer membrane proteins (OMP) expressing iron-regulated OMP (IROMP) in conferring protection against experimental challenge exposure. ANIMALS: 52 male New Zealand White rabbits. PROCEDURE: Rabbits were vaccinated intranasally on days 0, 7, and 14; some vaccines included cholera toxin (CT) as an adjuvant. Concentrations of intranasal IgA and serum IgG antibodies against P multocida OMP were determined. In experiment A, rabbits were vaccinated with either phospate-buffered saline solution (PBSS), PBSS-CT, OMP-CT, or IROMP-CT, challenge-exposed intranasally on day 16, and euthanatized and necropsied on day 28. Rabbits were also vaccinated with OMP or IROMP without CT and were not challenge-exposed. In experiment B, rabbits were vaccinated with PBSS, PBSS-CT, IROMP, or IROMP-CT. On day 17, rabbits were challenge-exposed intranasally. Nasal bacteria and antibodies were determined on day 24. RESULTS: In experiment A, OMP-CT vaccination stimulated mucosal and systemic antibody responses to the bacterium and enhanced resistance against challenge exposure. Intranasal bacterial counts were not significantly reduced. Vaccination with IROMP-CT stimulated mucosal and systemic antibodies, enhanced resistance to challenge exposure, and significantly reduced nasal bacterial counts. In experiment B, natural infection was detected in several rabbits at challenge exposure; however, IROMP-CT-vaccinated rabbits had significantly higher serum and nasal antibody responses, compared with other rabbits IROMP-CT-vaccinated rabbits had significantly lower nasal bacterial counts compared to control rabbits. CONCLUSIONS AND CLINICAL RELEVANCE: Intranasal vaccination of rabbits with P multocida outer membranes containing IROMP and CT stimulated immunity against experimental pneumonic pasteurellosis.     

Field Techniques in Zoo and Wildlife Conservation Work

Wildlife conservation fieldwork and field-like situations in zoo settings can be challenging to veterinarians and include restraining, sedating/anesthetizing, examining, and sampling wild animals. The lack of amenities and utilities such as running water or electricity, climatic conditions, biting insects, and even the general public can all be a hindrance when working with animals in this environment. Zoonotic diseases and local conflicts, as well as the work itself, can all be hazards. On the basis of our combined experience, with field examples set in Scotland, working practices and suggestions for fieldwork equipment and the processing of samples are outlined. Equipment, references for obtaining additional information, and considerations for capture and anesthesia in the field are also covered. The importance of good communications, within the animal care team, with stakeholders, and with the general public, is emphasized. Potential health and environmental hazards are discussed, with recommendations on protective clothing and resources to identify these hazards.     

First glimpse into the origin and spread of the Asian longhorned tick,Haemaphysalis longicornis,in the United States

Established populations of Asian longhorned ticks (ALT), Haemaphysalis longicornis, were first identified in the United States (US) in 2017 by sequencing the mitochondrial cytochrome c oxidase subunit I (cox1) ‘barcoding’ locus followed by morphological confirmation. Subsequent investigations detected ALT infestations in 12, mostly eastern, US states. To gain information on the origin and spread of US ALT, we (1) sequenced cox1 from ALT populations across 9 US states and (2) obtained cox1 sequences from potential source populations [China, Japan and Republic of Korea (ROK) as well as Australia, New Zealand and the Kingdom of Tonga (KOT)] both by sequencing and by downloading publicly available sequences in NCBI GenBank. Additionally, we conducted epidemiological investigations of properties near its initial detection locale in Hunterdon County, NJ, as well as a broader risk analysis for importation of ectoparasites into the area. In eastern Asian populations (China/Japan/ROK), we detected 35 cox1 haplotypes that neatly clustered into two clades with known bisexual versus parthenogenetic phenotypes. In Australia/New Zealand/KOT, we detected 10 cox1 haplotypes all falling within the parthenogenetic cluster. In the United States, we detected three differentially distributed cox1 haplotypes from the parthenogenetic cluster, supporting phenotypic evidence that US ALT are parthenogenetic. While none of the source populations examined had all three US cox1 haplotypes, a phylogeographic network analysis supports a northeast Asian source for the US populations. Within the United States, epidemiological investigations indicate ALT can be moved long distances by human transport of animals, such as horses and dogs, with smaller scale movements on wildlife. These results have relevant implications for efforts aimed at minimizing the spread of ALT in the United States and preventing additional exotic tick introductions.     

Globulin Expression in Grain of Australian Hard Wheat Cultivars Is Affected by Growth Environment

Our aim was to study changes in wheat proteomes across different growth locations as the first step in linking protein composition with functional changes in grains produced with commercial production systems. Soluble and insoluble proteins were extracted sequentially from grain of three commercial wheat cultivars grown at four locations in New South Wales, Australia, during a single season. Bands were separated with SDS‐PAGE and identified by peptide mass fingerprinting. Quantitative changes in the electrophoretic patterns were observed mainly in the insoluble polypeptides of molecular mass 40,000–70,000 for all three cultivars grown at two of the four locations. These proteins were identified as mainly globulin and serpin isoforms, as well as triticin. Other proteins with changed expression included disease‐resistance proteins, class III peroxidase, starch branching enzyme I, β‐amylase, and storage proteins. Two‐dimensional electrophoretic analysis was performed on two of the same wheat cultivars grown at one of the locations during two consecutive seasons. Protein spots that varied between seasons consisted of globulin and serpin isoforms, triticin, HMW glutenin, γ‐gliadin, starch branching enzyme IIb, and α‐amylase. The implications of the upregulation of globulin and triticin on whole meal flour quality, through their participation in polymerization of the gluten network, are considered.