The ongoing human H7N9 influenza infections highlight the threat of emerging avian influenza viruses. In 2011, an avian H3N8 influenza virus isolated from moribund New England harbour seals was shown to have naturally acquired mutations known to increase the transmissibility of highly pathogenic H5N1 influenza viruses. To elucidate the potential human health threat, here we evaluate a panel of avian H3N8 viruses and find that the harbour seal virus displays increased affinity for mammalian receptors, transmits via respiratory droplets in ferrets and replicates in human lung cells. Analysis of a panel of human sera for H3N8 neutralizing antibodies suggests that there is no population-wide immunity to these viruses. The prevalence of H3N8 viruses in birds and multiple mammalian species including recent isolations from pigs and evidence that it was a past human pandemic virus make the need for surveillance and risk analysis of these viruses of public health importance.

We used six beef steers (377 +/- 12.7 kg) to evaluate the effect of advancing season on dietary composition, forage intake, and digestion. Six 10-d sample collections were conducted from mid-June to mid-December 1995. Diet quality data demonstrated a linear (P < .01) decline in CP and in vitro OM digestibility (IVOMD), whereas NDF, ADF, acid detergent-insoluble CP (ADICP; percentage of CP), and undegradable intake protein (UIP; percentage of CP) increased linearly (P < .01) with advancing season. Fecal output and ruminal OM fill (percentage of BW) demonstrated linear and cubic responses (P < .10) across the grazing season. Intake of OM (percentage of BW) followed quadratic and cubic (P < .10) patterns across season. Rate (percentage per hour) of in situ NDF disappearance (ISNDFD) decreased and lag time increased linearly (P < .01) with advancing season. Likewise, quadratic (P < .07) and cubic (P < .06) responses were observed for rate and lag time of ISNDFD. The rapidly degraded CP fraction increased (P < .10) linearly, and the rate of in situ CP disappearance (ISCPD) followed a linear and quadratic decrease (P < .10) with advancing season. In summary, these data indicate decreases (P < .10) in dietary CP, IVOMD, ISNDFD, and ISCPD with advancing season. In addition, seasonal increases (P < .10) in forage NDF, ADF, ADICP, UIP (percentage of DM) and fecal output were observed and correspond to the grazing of increasingly mature forage. These data suggest that mixed-grass range forage consumed by cattle in western North Dakota during November and December is deficient in degradable intake protein (DIP). Investigation of protein supplementation (particularly DIP) during these times is warranted.

While much is known about the prevalence of influenza viruses in North America and Eurasia, their prevalence in birds and mammals in South America is largely unknown. To fill this knowledge gap and provide a baseline for future ecology and epidemiology studies, we conducted 2 years of influenza surveillance in the eastern plains (Los Llanos) region of Colombia. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) identified influenza viruses in wild birds, domestic poultry, swine and horses. Prevalence ranged from 2.6% to 13.4% across species. Swine showed the highest prevalence and were infected primarily with 2009 pandemic H1N1 (pH1N1) viruses genetically related to those in humans. In addition, we isolated H5N2 viruses from two resident species of whistling ducks (genus Dendrocygna) that differed completely from previous South American isolates, instead genetically resembling North American wild bird viruses. Both strains caused low pathogenicity in chickens and mammals. The prevalence and subtype diversity of influenza viruses isolated from diverse species within a small area of Colombia highlights the need for enhanced surveillance throughout South America, including monitoring of the potential transmissibility of low-pathogenic H5N2 viruses from wild birds to domestic poultry and the emergence of reassortant viruses in domestic swine.

Six foals were inoculated intrabronchially with a suspension of Corynebacterium equi. Six weeks before this challenge, three foals were vaccinated with a C. equi bacterin. Three foals were unvaccinated controls. All foals developed a severe bronchopneumonia in the inoculated lung, indicating that vaccination was not protective. Three foals (two vaccinated, one control) were killed eight to nine days after infection. One control died on day 9 with lesions of disseminated intravascular coagulation. The remaining two foals (one vaccinated, one control) were killed on day 17. C. equi was cultured in large numbers from affected lung and bronchial lymph nodes, and in smaller numbers from unaffected lung, spleen, and liver in all foals. In the 8- to 9-day-old lung lesions, the alveoli were filled with macrophages, neutrophils, and multinucleate giant cells and most contained numerous C. equi. The few foci of alveolar necrosis were associated with groups of bacteria-laden macrophages undergoing degeneration. In the lesions of 17-day duration, there was extensive parenchymal destruction with little fibrous tissue reaction. Lesions common to both groups included hyperplastic bronchiolitis, pulmonary edema, and perivascular lymphocytic cuffs and a pyogranulomatous lymphadenitis in bronchial nodes. One vaccinated foal had a microscopic pyogranulomatous colitis. The lesions in the experimentally infected foals are compared with those in naturally infected foals and discussed in terms of likely pathogenetic mechanisms involved in C. equi pneumonia in foals.

An Old English Sheepdog developed multiple tumor-like masses bilaterally on the head, back, elbows, and hocks, and severe swelling of all digital pads. The gross lesions were the result of accumulation of myxedematous connective tissue in the dermis. Abundant glycosaminoglycan-rich ground substance was confirmed by colloidal iron, toluidine blue and alcian blue stains. The dog also had a mixed follicular-compact cellular carcinoma in the left thyroid gland. The right thyroid had a tumor composed of anaplastic mesenchymal cells forming myxomatous matrix and islands of abnormal cartilage closely integrated, and possibly contiguous, with a follicular-compact cellular carcinoma. The cellular atypism and numerous aberrant mitotic figures in the mesenchymal areas suggested malignancy, although pulmonary metastases derived only from the thyroid carcinoma. Clinically, the dog showed no signs of hypo- or hyperthyroidism, although a resting serum T-4 was slightly below normal.

No abstract

The objective of this study was to evaluate the effects of the source of silage, cereal grain, and their interaction on growth performance, digestibility, and carcass characteristics of finishing beef cattle. Using a completely randomized design within an 89-d finishing study, 288 steers were randomly assigned to 1 of 24 pens (12 steers/pen) with average steer body weight (BW) within a pen of 464 kg ± 1.7 kg (mean ± SD). Diets were arranged in a 2 × 3 factorial with corn silage (CS) or barley silage (BS) included at 8% (dry matter [DM] basis). Within each silage source, diets contained dry-rolled barley grain (BG; 86% of DM), dry-rolled corn grain (CG; 85% of DM), or an equal blend of BG and CG (BCG; 85% of DM). Total tract digestibility of nutrients was estimated from fecal samples using near-infrared spectroscopy. Data were analyzed with pen as the experimental unit using the Mixed Model of SAS with the fixed effects of silage, grain, and the two-way interaction. Carcass and fecal kernel data were analyzed using GLIMMIX utilizing the same model. There were no interactions detected between silage and grain source. Feeding CG increased (P &lt; 0.01) DM intake by 0.8 and 0.6 kg/d relative to BG and BCG, respectively. Gain-to-feed ratio was greater (P = 0.04) for BG (0.172 kg/kg) than CG (0.162 kg/kg) but did not differ from BCG (0.165 kg/kg). Furthermore, average daily gain (2.07 kg/d) and final body weight did not differ among treatments (P ≥ 0.25). Hot carcass weight (HCW) was 6.2 kg greater (372.2 vs. 366.0 kg; P &lt; 0.01) and dressing percentage was 0.57 percentage units greater (59.53 vs. 58.96 %; P = 0.04) for steers fed CS than BS, respectively. There was no effect of dietary treatment on the severity of liver abscesses (P ≥ 0.20) with 72.0% of carcasses having clear livers, 24.4% with minor liver abscesses, and 3.6% with severe liver abscesses. Digestibility of DM, organic matter, crude protein, neutral detergent fiber, and starch were greater for BG (P &lt; 0.01) than CG or BCG. As expected, grain source affected the appearance of grain kernels in the feces (P ≤ 0.04). Feeding CS silage increased the appearance of fractured corn kernels (P = 0.04), while feeding BS increased fiber appearance in the feces (P = 0.02). Current results indicate that when dry rolled, feeding BG resulted in improved performance and digestibility compared with CG and BCG. Even at low inclusion levels (8% of DM), CS resulted in improved carcass characteristics relative to BS.

Abstract. The intragastric inoculation of a suspension of Corynebacterium equi on five consecutive days induced severe ulcerative colitis, typhilitis, and lymphadenitis of colonic and cecal nodes in two ponies necropsied three weeks after infection. No gross lesions were observed in two ponies necropsied ten days after infection. A single inoculum of equivalent size failed to induce gross lesions in four ponies killed at ten or 20 days after infection. Microscopic lesions consistent with early C. equi infection of Peyer's patches were seen in two of the ponies killed ten days after infection. Only one small pulmonary abscess occurred in one foal, suggesting that intestinal lesions are not likely the usual precursor of pulmonary disease in naturally infected foals. The gross and microscopic lesions in the experimentally infected ponies were typical of the intestinal form of naturally occurring C. eqzii associated disease in foals.