Risk factors for early death or euthanasia within 100 days of diagnosis in dogs with meningoencephalitis of unknown origin.

Meningoencephalitis of unknown origin (MUO) in the dog is an inflammatory condition of the central nervous system with variable short- and long-term prognosis. Previous studies have attempted to identify risk factors for early death; however, the findings were inconsistent and prognostication and treatment selection remain difficult for cases of MUO. The aim of this study was to compare the influence of putative prognostic factors on early survival in dogs with MUO. Logistic regression was used to analyse the effect of clinical and magnetic resonance imaging (MRI) features at diagnosis and type of immune-suppressive treatment received on survival at three-time points; 7 days, 30 days, and 100 days post-diagnosis. Ninety eight dogs were included. Dogs that were obtunded at presentation had a 6.6 times increased odds of death in the first 7 days after diagnosis, a 2.1 times increased risk of death 8-30 days after diagnosis, and a 1.9 times increased risk of death 31-100 days after diagnosis. No other clinical, MRI feature, or treatment was found to have a significant influence on survival. Obtundation at presentation was found to increase risk of early euthanasia in dogs with MUO, while the addition of an IV infusion of cytarabine to immune-suppressive corticosteroid therapy (prednisolone and/or dexamethasone) at initial treatment did not improve the odds of survival at 7, 30, or 100 days after diagnosis.

Evaluation of a Preharvest Bacteriophage Therapy for Control of Salmonella within Bovine Peripheral Lymph Nodes.

ABSTRACT: A series of proof-of-concept studies were developed to determine whether a commercial bacteriophage cocktail could be utilized for the mitigation of Salmonella in bovine peripheral lymph nodes (LNs). The first objective sought to determine whether exogenous phage could be isolated from the LNs following administration. If isolation were successful, the second objective was to determine whether the phage in the LNs could effectively reduce Salmonella. Salmonella Montevideo was inoculated intradermally at multiple sites and multiple times, followed by delivery of the phage cocktail subcutaneously in two injections around each of the right and left prescapular and subiliac LNs. At the conclusion of each study, animals were euthanized, and the popliteal, prescapular, and subiliac LNs were examined. The inoculated phage was successfully isolated from the LNs; transmission electron microscopy revealed phages in the LNs of the treated cattle, and these phages were identical to those in the cocktail. Levels of phage were higher (P < 0.01) in the prescapular and subiliac LNs in the phage-treated than in the control cattle. In subsequent studies, the protocols were modified to increase Salmonella and phage levels within the LNs. Compared with the first study, overall Salmonella levels were increased in the LNs, and phage treatment decreased (P < 0.01) Salmonella in the some of the LNs. Phage levels were numerically but not significantly increased (P = 0.12) in the treated cattle. The final study was modified, hypothesizing that a 48-h postmortem period before LN removal would facilitate phage-Salmonella interaction; however, no differences (P > 0.10) in Salmonella levels were found among treatments. Salmonella-specific phages administered to live cattle can translocate to the LNs; however, these phages had limited to no effect on Salmonella in these LNs under these experimental conditions.

Quantitative Diffusion and Spectroscopic Neuroimaging Combined with a Novel Early-Developmental Assessment Improves Models for 1-Year Developmental Outcomes.

BACKGROUND AND PURPOSE: Preterm infants are at risk for overt and silent CNS injury, with developmental consequences that are difficult to predict. The novel Specific Test of Early Infant Motor Performance, administered in preterm infants at term age, is indicative of later developmental gross motor and cognitive scores at 12 months. Here, we assessed whether functional performance on this early assessment correlates with CNS integrity via MR spectroscopy or diffusional kurtosis imaging and whether these quantitative neuroimaging methods improve predictions for future 12-month developmental scores. MATERIALS AND METHODS: MR spectroscopy and quantitative diffusion MR imaging data were acquired in preterm infants (n = 16) at term. Testing was performed at term and 3 months using the Specific Test of Early Infant Motor Performance and the Bayley Scales of Infant and Toddler Development, Third Edition, at 12 months. We modeled the relationship of MR spectroscopy and diffusion MR imaging data with both test scores via multiple linear regression. RESULTS: MR spectroscopy NAA ratios at a TE of 270 ms in the frontal WM and basal ganglia and kurtosis metrics in major WM tracts correlated strongly with total Specific Test of Early Infant Motor Performance scores. The addition of MR spectroscopy and diffusion separately improved the functional predictions of 12-month outcomes. CONCLUSIONS: Microstructural integrity of the major WM tracts and metabolism in the basal ganglia and frontal WM strongly correlate with early developmental performance, suggesting that the Specific Test of Early Infant Motor Performance reflects CNS integrity after preterm birth. This study demonstrates that combining quantitative neuroimaging and early functional movement improves the prediction of 12-month outcomes in premature infants.

Evaluation of the Efficacy of Three Direct Fed Microbial Cocktails To Reduce Fecal Shedding of Escherichia coli O157:H7 in Naturally Colonized Cattle and Fecal Shedding and Peripheral Lymph Node Carriage of Salmonella in Experimentally Infected Cattle.

Two experiments were conducted to evaluate the feeding of direct fed microbials (DFMs) on fecal shedding of Escherichia coli O157:H7 in naturally infected cattle (experiment I) and on Salmonella in the feces and peripheral lymph nodes (PLNs) of experimentally infected cattle (experiment II). Thirty cattle, 10 per treatment, were used in each experiment. Treatments in experiment I consisted of a control (lactose carrier only); DFM1, a 1:1 ratio of Enterococcus faecium and Lactobacillus animalis; and DFM2, a 1:1 ratio of Lactobacillus acidophilus and Pediococcus acidilactici. In Experiment II, DFM1 was replaced with DFM3, a 1:2 ratio of Lactobacillus reuteri and other Lactobacillus strains. Additives were mixed in water and applied as a top-dressing to each pen's daily ration for 50 days. Approximately half-way through each experiment, the DFM concentration was doubled for the remainder of the study. Fecal samples were collected throughout experiment I and cultured for E. coli O157:H7. Cattle in experiment II were inoculated intradermally with Salmonella Montevideo on days 32, 37, and 42 and then necropsied on days 49 and 50 (five cattle per treatment on each day). Innate immune function was assessed on days 29, 49, and 50. In experiment I, fecal concentration and prevalence of E. coli O157:H7 were not different (P > 0.10) nor was there an effect (P = 0.95) on the percentage of super shedders (cattle shedding ≥3.0 log CFU/g of feces). In experiment II, no treatment differences (P > 0.05) were observed for Salmonella in the PLNs except for the inguinal nodes, which had a significantly lower Salmonella prevalence in DFM-supplemented cattle than in the controls. Immune function, as measured by monocyte nitric oxide production and neutrophil oxidative burst, was decreased (P < 0.05) in the DFM treatment groups. Although results of this research indicate little to no effect of these DFMs on E. coli O157:H7 or Salmonella in cattle, an increase in the duration of administration to that similar to what is used for commercial cattle might elicit treatment differences.

Prolonged Microgravity Affects Human Brain Structure and Function.

BACKGROUND AND PURPOSE: Widespread brain structural changes are seen following extended spaceflight missions. The purpose of this study was to investigate whether these structural changes are associated with alterations in motor or cognitive function. MATERIALS AND METHODS: Brain MR imaging scans of National Aeronautics and Space Administration astronauts were retrospectively analyzed to quantify pre- to postflight changes in brain structure. Local structural changes were assessed using the Jacobian determinant. Structural changes were compared with clinical findings and cognitive and motor function. RESULTS: Long-duration spaceflights aboard the International Space Station, but not short-duration Space Shuttle flights, resulted in a significant increase in total ventricular volume (10.7% versus 0%, P < .001, n = 12 versus n = 7). Total ventricular volume change was significantly associated with mission duration (r = 0.72, P = .001, n = 19) but negatively associated with age (r = -0.48, P = .048, n = 19). Long-duration spaceflights resulted in significant crowding of brain parenchyma at the vertex. Pre- to postflight structural changes of the left caudate correlated significantly with poor postural control; and the right primary motor area/midcingulate correlated significantly with a complex motor task completion time. Change in volume of 3 white matter regions significantly correlated with altered reaction times on a cognitive performance task (bilateral optic radiations, splenium of the corpus callosum). In a post hoc finding, astronauts who developed spaceflight-associated neuro-ocular syndrome demonstrated smaller changes in total ventricular volume than those who did not (12.8% versus 6.5%, n = 8 versus n = 4). CONCLUSIONS: While cautious interpretation is appropriate given the small sample size and number of comparisons, these findings suggest that brain structural changes are associated with changes in cognitive and motor test scores and with the development of spaceflight-associated neuro-optic syndrome.

25-Hydroxy vitamin D3 serum concentration in dogs with acute polyradiculoneuritis compared to matched controls.

OBJECTIVES: To determine if dogs with acute polyradiculoneuritis have lower serum 25-hydroxy vitamin D3 concentration compared to a control group of dogs with idiopathic epilepsy. MATERIALS AND METHODS: Retrospective case-control study of 21 dogs with acute canine polyradiculoneuritis and 21 control dogs with idiopathic epilepsy matched for year and season of presentation from a referral hospital population in the UK. Serum concentration of 25-hydroxy vitamin D3 was compared between groups using Student's t-test. RESULTS: Dogs with acute canine polyradiculoneuritis had significantly lower (P=0·033) serum 25-hydroxy vitamin D3 concentration (87·1 nmol/L ±55·4 nmol/L) compared to a control group with idiopathic epilepsy (113 nmol/L ±66·3 nmol/L). CLINICAL SIGNIFICANCE: The cause and clinical significance of the altered vitamin D status in dogs with acute polyradiculoneuritis are not clear and require further investigation. Our findings pave the way for improved understanding of acute canine polyradiculoneuritis and, potentially, improved clinical management, if a causal role for 25-hydroxy vitamin D3 is defined.

Unique prefrontal GABA and glutamate disturbances in co-occurring bipolar disorder and alcohol dependence.

Bipolar disorder (BD) and alcohol dependence (AD) frequently co-occur, and co-occurring BD and AD are associated with devastating public health costs. Minimal neurobiological research exists to guide the development of effective treatments for this treatment-resistant population. We believe the present study represents the first investigation of prefrontal gamma-aminobutyric acid (GABA) and glutamate levels in co-occurring BD and current AD. The participants were 78 individuals who met DSM-IV criteria for BD I/II and current AD (n=20), BD I/II alone (n=19), current AD alone (n=20) or no diagnosis (n=19). The participants completed a baseline diagnostic visit, then returned approximately 4 days later for a two-dimensional J-resolved proton magnetic resonance spectroscopy (1H-MRS) acquisition in dorsal anterior cingulate cortex (dACC). All participants were required to demonstrate ⩾1 week of abstinence from alcohol/drugs via serial biomarker testing before 1H-MRS. A 2 × 2 factorial analysis of variance of cerebrospinal fluid (CSF)-corrected GABA/water concentrations demonstrated a significant BD × AD interaction (F=2.91, P<0.05), signifying uniquely low levels of GABA in BD+AD; this effect doubled when the sample was restricted to individuals who consumed alcohol within 2 weeks of 1H-MRS. There were no overall effects of BD/AD on CSF-corrected glutamate/water levels. However, the BD × AD interaction, signifying uniquely low levels of glutamate in BD+AD, approached statistical significance (F=3.83, P=0.06) in individuals who consumed alcohol within 2 weeks of 1H-MRS. The dACC GABA levels were significantly, negatively associated with Barratt Impulsiveness Scale (r=-0.28, P=0.02) and Obsessive Compulsive Drinking Scale (r=-0.35, P<0.01) scores. If replicated, these results may suggest that future treatment studies should preferentially evaluate therapeutics in BD+AD known to increase prefrontal GABA and glutamate levels.

An exploratory study into factors influencing development of acute canine polyradiculoneuritis in the UK.

OBJECTIVES: To investigate whether the development of acute canine polyradiculoneuritis is associated with various putative risk factors. MATERIALS AND METHODS: Retrospective case-control study with conditional logistic regression analysis from a referral hospital population in the UK where controls were matched for year of presentation. RESULTS: Forty-three cases were identified with acute canine polyradiculoneuritis and 86 controls were selected. Jack Russell terriers and West Highland white terriers were found to have a significantly greater odds of developing acute canine polyradiculoneuritis compared to a mixed baseline group of dogs. The odds of developing acute canine polyradiculoneuritis were greater in the autumn and winter compared to spring. Vaccination, rural/urban habitation, sex, neuter status and age were not associated with development of acute canine polyradiculoneuritis in our population of dogs. CLINICAL SIGNIFICANCE: Breed and season were associated with development of acute canine polyradiculoneuritis. However, this is a small sample and so this observation needs confirmation in further studies and other factors may also be involved. Nevertheless, these findings may be important in further understanding the aetiopathogenesis of this condition.

Prognostic Factors Associated with Recovery of Ambulation and Urinary Continence in Dogs with Acute Lumbosacral Spinal Cord Injury.

BACKGROUND: Limited information is available about prognostic factors for recovery after spinal cord injury (SCI) to the L4-S3 segments. Previous research suggests that L4-S3 SCI does not have a worse prognosis than T3-L3 SCI. HYPOTHESIS/OBJECTIVES: To elucidate prognostic factors for regaining urinary continence and ambulation in dogs with L4-S3 SCI and compare prognosis to T3-L3 SCI. ANIMALS/METHODS: A retrospective study on 61 nonambulatory dogs with L4-S3 SCI, matched to dogs with T3-L3 SCI, compared 3 weeks after onset. Prognostic factors explored using logistic regression and used for matching: nonchondrodystrophic dogs >15 kg versus dogs that were chondrodystrophic or <15 kg; compressive versus noncompressive lesions; presence versus absence of conscious pain perception (CPP); and lower vs upper motor neuron (LMN/UMN) incontinence. RESULTS: Fewer L4-S3 dogs regained continence compared to T3-L3 dogs (64 vs 85%, P = .0033), but no difference existed for regaining ambulation (66 vs 75%, P = .1306). In L4-S3 SCI dogs, fewer dogs regained continence with loss of CPP (P < .001), LMN incontinence (P = .004), and noncompressive lesions (P = .006). Negative prognostic factors for regaining ambulation included absent CPP (P < .001) and large nonchondrodystrophic breed (P = .022). CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with L4-S3 SCI have a poorer short-term prognosis than do dogs with T3-L3 SCI. Dogs with L4-S3 SCI had a poor prognosis with loss of CPP, or noncompressive lesions combined with LMN incontinence. Small-breed or chondrodystrophic dogs with retained CPP, compressive lesions, and UMN incontinence had an excellent prognosis. These findings may help guide decision-making in L4-S3 SCI.

Evidence supporting vertical transmission of Salmonella in dairy cattle.

We set out to investigate whether Salmonella enterica could be recovered from various tissues of viable neonatal calves immediately following parturition. Eleven samples were aseptically collected from each of 20 calves and consisted of both left and right subiliac and prescapular lymph nodes (LN), mesenteric LN, spleen and liver, as well as intestinal tissue (including luminal contents) from the small intestine, caecum, spiral colon and rectum. In addition, a faecal sample was collected from 19 of the dams. Salmonella was recovered from at least one sample from 10 of the 20 neonates. Across all calves, Salmonella was recovered from 12·7% of all samples and from LN in particular, Salmonella was recovered from 10·0%, 5·0%, and 5·0% of subiliac, prescapular, and mesenteric LN, respectively. Within calves, Salmonella was recovered from 0% to 73% of samples and across tissues, estimates of Salmonella prevalence were greatest in the caecum (30%) but was never recovered from the right pre-scapular LN. These data provide evidence of vertical transmission from a dam to her fetus such that viable calves are born already infected and thereby not requiring faecal-oral exposure for transmission. This new knowledge ought to challenge - or at least add to - existing paradigms of Salmonella transmission dynamics within cattle herds.

Investigation into Possible Differences in Salmonella Prevalence in the Peripheral Lymph Nodes of Cattle Derived from Distinct Production Systems and of Different Breed Types.

Previous research demonstrated significant variation in the prevalence of Salmonella in peripheral lymph nodes (LNs) of feedlot cattle and cull cows, with greater prevalence in feedlot cattle. Therefore, we performed experiments to investigate whether these differences in Salmonella prevalence in subiliac LNs are due to, or influenced by, breed, which in many respects is a proxy for the production system in which the animal is derived. Holstein steers are a by-product of dairy systems, and beef steers are an intended product of commercial beef operations. For the first experiment, Holstein and beef steers originating from the same feedlot and harvested on the same day were sampled. Of the 467 Holstein and 462 beef cattle LNs collected, 62.1% of Holstein and 59.7% of beef cattle samples harbored Salmonella (P = 0.46; qualitative culture), with 51.2 and 48.9% of samples containing quantifiable concentrations (P = 0.49), respectively. The concentration of Salmonella within the LN followed a decreasing trend over the collection period (May to October), averaging 1.4 log CFU/g of LN for both Holstein and beef cattle samples (P = 0.78). In a second experiment, we compared 100% Brahman cattle to their beef cattle counterparts, as we hypothesized that the resistance of Brahman cattle to insects may reduce Salmonella transmission via biting insects. Of the 42 Brahman and 31 beef cattle LNs collected, the concentration of Salmonella within the LN averaged 3.0 log CFU/g for Brahman cattle and 2.9 log CFU/g for beef cattle samples (P = 0.30). Using qualitative culture, we recovered Salmonella from 100% of LNs from Brahman cattle and 97% of beef cattle samples (P = 0.25). Results of this research indicate that the differences observed are not due to breed and are likely a function of age, immune function, or other factors yet to be identified. Understanding which cattle are more likely to harbor Salmonella within LNs will aid in targeting both pre- and postharvest intervention strategies.

Nutrient database improvement project: Separable components and proximate composition of raw and cooked retail cuts from the beef loin and round.

Beef nutrition research has become increasingly important domestically and internationally for the beef industry and its consumers. The objective of this study was to analyze the nutrient composition of ten beef loin and round cuts to update the nutrient data in the USDA National Nutrient Database for Standard Reference. Seventy-two carcasses representing a national composite of Yield Grade, Quality Grade, sex classification, and genetic type were identified from six regions across the U.S. Beef short loins, strip loins, tenderloins, inside rounds, and eye of rounds (NAMP # 173, 175, 190A, 169A, and 171C) were collected from the selected carcasses and shipped to three university meat laboratories for storage, retail fabrication, and raw/cooked analysis of nutrients. Sample homogenates from each animal were analyzed for proximate composition. These data provide updated information regarding the nutrient status of beef, in addition, to determining the influence of Quality Grade, Yield Grade, and sex classification on nutrient composition.

Structural Brain Changes following Long-Term 6° Head-Down Tilt Bed Rest as an Analog for Spaceflight.

BACKGROUND AND PURPOSE: Following long-term spaceflight, a subset of the National Aeronautics and Space Administration astronauts present with visual impairment and increased intracranial pressure, known as visual impairment and intracranial pressure syndrome. We investigated structural brain changes following long-term head-down tilt bed rest as a spaceflight analog. MATERIALS AND METHODS: Volumetric analysis was performed on structural pre- and post-bed rest brain MR images. RESULTS: Comparing post-bed rest to pre-bed rest images, we found the following: 1) no significant group differences in GM, WM, CSF, or ventricular volumes; 2) shift of the center of mass of the brain upward and posterior rotation of the brain relative to the skull; 3) a significant correlation between posterior brain rotation and changes in ventricular volume; and 4) significant increases in brain tissue density in regions at the vertex, including the frontoparietal lobes, with contraction of adjacent extra-axial CSF spaces, and significant decreases in tissue density in areas along the base of the brain, including the orbitofrontal cortex. CONCLUSIONS: We observed widespread morphologic changes with brain tissue redistribution in response to gravity changes; possible associated functional changes are unknown. The observation that ventricular change is correlated to posterior brain rotation suggests an alteration in CSF homeostasis. Ultimately, to elucidate any structural changes that may play a role in visual impairment and intracranial pressure syndrome, volumetric analysis of pre- and postflight structural scans of astronauts is needed.

Oral salmonella challenge and subsequent uptake by the peripheral lymph nodes in calves.

Previous attempts to infect peripheral lymph nodes (PLNs) with Salmonella via oral inoculation have been inconsistent. Therefore, we performed a series of experiments to determine whether multiple exposures to an oral challenge would result in Salmonella-positive PLN in cattle. In each of three experiments, calves were inoculated with Salmonella Montevideo. In the first experiment, calves were challenged with either no Salmonella (control), a single oral dose (∼10(10); PCON), or 10 consecutive doses in water (∼10(3); WAT). The positive control treatment resulted in an increase (P < 0.05) in the percentage of Salmonella-positive PLNs, compared with the WAT-treated and control animals. Experiments 2 and 3 were designed to additionally determine if the stress associated with feed and water deprivation influences the systemic spread of Salmonella from the gastrointestinal tract to PLNs. Following 14 days of oral inoculation (average 7.1 × 10(4) CFU/day) in experiment 1, Salmonella was recovered from one subiliac and one superficial cervical lymph node of calves that were deprived of feed and water (72 h). No treatment differences (P > 0.05) were observed between control and deprived calves. Based on the poor recovery of Salmonella from the PLNs in WAT-challenged calves in experiments 1 and 2, a higher challenge dose (average 1.2 × 10(7) CFU) was used in experiment 3. The increased dose resulted in the recovery of the challenge strain of Salmonella from the PLNs (70.8 and 75.0% of control and deprived calves, respectively). However, no treatment differences (P > 0.05) were observed between control and deprived calves. Results of this research demonstrated that a substantial oral challenge is required to produce Salmonella-positive PLNs. However, as the challenge periods examined herein were considerably shorter compared with the normal time spent by cattle in feedlots, increased exposure time to lower doses may produce the same effect observed in experiment 3.

Prevalence of Chiari-like malformations in clinically unaffected dogs.

BACKGROUND: The importance of Chiari-like malformation (CM) in the generation of clinical signs or the formation of syringomyelia in dogs is incompletely understood, partly because the prevalence of various CM definitions in unaffected dogs is unknown. HYPOTHESIS/OBJECTIVES: The aims were: to estimate the prevalence of CM in dogs asymptomatic for CM or syringomyelia, according to 3 currently used definitions; and, to investigate the effect of brachycephaly and head position during magnetic resonance (MR) imaging on estimates of the prevalence of CM. ANIMALS: One ninety-nine client-owned dogs without apparent signs of CM or syringomyelia. METHODS: Blinded, retrospective analysis. Archived MR images were analyzed for evidence of cerebellar indentation and impaction into or herniation through the foramen magnum. Logistic regression analysis was used to investigate the relationship of CM diagnosis with head position and the cranial index (a measure of brachycephaly). RESULTS: In 185 non-Cavalier King Charles Spaniel (CKCS) dogs, indentation was identified in 44% (95% CI, 47-51%) and impaction in 22% (95% CI, 16-28%). No asymptomatic, non-CKCS dogs showed herniation. Regression analysis showed a significant increase in the odds of indentation and impaction in an extended head position and as the cranial index increased (became more brachycephalic). CONCLUSIONS AND CLINICAL IMPORTANCE: The high prevalence of cerebellar indentation and impaction suggests that they may be normal anatomical variations and therefore unsuitable as definitions of CM. We suggest that future research into CM in dogs should define cases and controls more strictly so that overlap between normal and abnormal animals is minimized.

Biological responses of beef steers to steroidal implants and zilpaterol hydrochloride.

British × Continental steers (n = 168; 7 pens/treatment; initial BW = 362 kg) were used to evaluate the effect of dose/payout pattern of trenbolone acetate (TBA) and estradiol-17ß (E2) and feeding of zilpaterol hydrochloride (ZH) on serum urea-N (SUN), NEFA, IGF-I, and E2 concentrations and LM mRNA expression of the estrogen (ER), androgen (ANR), IGF-I (IGF-IR), ß1-adrenergic (ß1-AR), and ß2-adrenergic (ß2-AR) receptors and IGF-I. A randomized complete block design was used with a 3 × 2 factorial arrangement of treatments. Main effects were implant (no implant [NI], Revalor-S [REV-S; 120 mg TBA + 24 mg E2], and Revalor-XS [REV-X; 200 mg TBA + 40 mg E2]) and ZH (0 or 8.3 mg/kg of DM for 20 d with a 3-d withdrawal). Steers were fed for 153 or 174 d. Blood was collected (2 steers/pen) at d -1, 2, 6, 13, 27, 55, 83, 111, and 131 relative to implanting; LM biopsies (1 steer/pen) were collected at d -1, 27, 55, and 111. Blood and LM samples were collected at d -1, 11, and 19 relative to ZH feeding. A greater dose of TBA + E2 in combination with ZH increased ADG and HCW in an additive manner, suggesting a different mechanism of action for ZH and steroidal implants. Implanting decreased (P < 0.05) SUN from d 2 through 131. Feeding ZH decreased (P < 0.05) SUN. Serum NEFA concentrations were not affected by implants (P = 0.44). There was a day × ZH interaction (P = 0.06) for NEFA; ZH steers had increased (P < 0.01) NEFA concentrations at d 11 of ZH feeding. Serum E2 was greater (P < 0.05) for implanted steers by d 27. Serum trenbolone-17ß was greater (P < 0.05) for implanted steers by d 2 followed by a typical biphasic release rate, with a secondary peak at d 111 for REV-X (P < 0.05) implanted steers. Implanting did not affect mRNA expression of the ANR or ER, but the IGF-IR and the ß1-AR and ß2-AR were less (P < 0.05) for REV-S than NI at d 55 and ß2-AR mRNA was less (P < 0.05) for REV-S than for REV-X. Expression of the IGF-IR and the ß1-AR at d 111 was greater (P< 0.05) for REV-X than for REV-S and NI at d 111, and the ß2-AR was less (P< 0.05) for REV-S than for REV-X. Feeding ZH did not affect mRNA expression of the ß1-AR and ß2-AR. Both implanting and feeding ZH decreased SUN, but a greater dose of TBA + E2 did not result in further decreases. In addition, feeding ZH increased serum NEFA concentrations. Metabolic changes resulting from implanting and feeding ZH may aid in explaining steer performance and carcass responses to these growth promotants.

Comparative effects of zilpaterol hydrochloride and ractopamine hydrochloride on live performance and carcass characteristics of calf-fed Holstein steers.

Holstein steers (n = 2,275) were assigned to 1 of 3 treatments: 1) a control diet containing no ß-agonists, 2) a diet that contained zilpaterol hydrochloride (ZH; 8.3 mg/kg [100% DM basis]) for 20 d with a 3-d withdrawal period before harvest, and 3) a diet that contained ractopamine hydrochloride (RH; 30.1 mg/kg [100% DM basis]) for 28 d before harvest. No differences (P ≥ 0.18) were detected between treatments for initial BW, BW at d 28, or DMI. Final BW, BW gain for the last 28 d, total BW gain, ADG for the last 28 d, and overall ADG were greater (P < 0.05) for steers fed ZH or RH than for steers fed the control diet. Additionally, G:F for the last 28 d and G:F for the entire trial was increased (P < 0.02) for steers fed ZH (0.147, 0.147) or RH (0.153, 0.151) compared to steers fed the control diet (0.134, 0.143), respectively. Steers fed ZH or RH had HCW that were 15.5 and 8.2 kg heavier (P ≤ 0.01) and LM areas that were 7.1 and 2.3 cm(2) larger (P < 0.01) than control cattle. Steers fed ZH also had dressed carcass yields that were 1.3% to 1.5% greater and USDA calculated yield grades that were decreased 0.16 to 0.23 units compared to RH and control steers. No differences (P ≥ 0.39) were found between treatments for marbling score, fat thickness, and percentage KPH. Steers fed ZH had an increased (P ≤ 0.04) percentage of yield grade 1 and 2 carcasses (15.1, 55.0) and a reduced (P ≤ 0.02) percentage of yield grade 3 carcasses (27.1) compared with those fed RH (10.5, 49.1, 36.1) or the control diet (9.0, 47.4, 36.4), respectively. Additionally, ZH-fed steers had a decreased (P ≤ 0.04) percentage of yield grade 4 and 5 carcasses (2.8) compared with steers fed the control diet (6.9). Steers fed ZH had an increased (P ≤ 0.01) percentage of USDA Select grading carcass (31.0%) and a decreased (P ≤ 0.01) percentage of USDA Choice grading carcasses (65.0%) compared with steers fed RH (25.8%, 70.2%) and no ß-agonist (24.8%, 72.0%), respectively. Feeding either ß-agonist to calf-fed Holstein steers increased live performance through increased BW, BW gain, and ADG. Furthermore, supplementing calf-fed Holstein steers with ZH provides greater improvements in HCW, LM area, and yield grade components, with a slight decrease in quality grade when compared to calf-fed Holstein steers supplemented with RH.

The impact of demographic, social, and environmental factors on the development of steroid-responsive meningitis-arteritis (SRMA) in the United Kingdom.

BACKGROUND: Steroid-responsive meningitis-arteritis (SRMA) is an inflammatory disease of dogs that is suspected to be immune-mediated. The development of other immune-mediated diseases has been linked to vaccinations, time of the year, geographic location, sex, neuter status, and breed. HYPOTHESIS/OBJECTIVES: To identify if the development of SRMA is associated with time of year, vaccination, geographic location, sex, neuter status, and breed. ANIMALS: Sixty SRMA cases and 180 controls, all ≤24 months of age and matched for year of presentation, from a referral hospital population in the United Kingdom. METHODS: Retrospective case-control study with unconditional logistic regression analysis. RESULTS: Beagles (P = .001), Border Collies (P = .001), Boxers (P = .032), Jack Russell Terriers (P = .001), Weimaraners (P = .048), and Whippets (P < .001) had significantly greater odds of developing SRMA in this population of dogs. Vaccination, time of year, geographic category, sex, and neuter status did not increase the odds of developing SRMA. CONCLUSIONS AND CLINICAL IMPORTANCE: Only breed increased the odds of developing SRMA. It would be prudent to investigate the genetics of the identified breeds to help elucidate the etiopathogenesis of SRMA.