Bovine intramammary infection associated immunogenic surface proteins of Streptococcus uberis.

In spite of the increasing prevalence of Streptococcus uberis mastitis, its pathogenesis and associated virulence factors are not clearly defined. The aim of this study was to identify virulence associated genes and their products that can be used to develop effective vaccine to control bovine S. uberis mastitis. S. uberis was co-cultured with primary bovine mammary epithelial cells (PBMEC) or infused into mammary gland of dairy cows. The messenger RNA (mRNA) from S. uberis associated with PBMEC after 2 h or 4 h of co-culture was purified and sequenced. Results showed that virulence-associated genes such as surface lipoprotein (slp), infection induced histidine kinase (iihK), infection induced response regulator (iirR) and extracellular sugar binding protein 1 and 2 (exsbP1 and exsbP2) were among the top-up-regulated genes. To verify this observation in vivo, quantitative real time PCR (qRT - PCR) was conducted on mRNA of S. uberis recovered from milk of infected mammary glands 24 h post infection. Results revealed that in vitro up-regulated virulence-associated genes were also significantly up regulated under in vivo conditions. The iihK and iirR are flanked by exsbP1 and exsbP2 genes and this entire operon seems to be involved in adaptation to glands micro-environment, survival and colonization of the bovine mammary glands. Based on immunogenic epitope prediction of proteins encoded by these up-regulated genes during early stages of host-bacterial interactions slp, exsbP1 and exsbP2 genes were selected, cloned and expressed in E. coli. The purified recombinant proteins (rSlP, rExsbP1 & rExsbP2) reacted strongly with convalescent serum from cows experimentally infected with S. uberis confirming that they are immunogenic. These proteins may serve as potential targets to develop an effective vaccine against S. uberis mastitis.

Short communication: Relationships among temperature-humidity index with rectal, udder surface, and vaginal temperatures in lactating dairy cows experiencing heat stress.

The objective of this study was to evaluate relationships between measurements of temperature-humidity index (THI) and rectal, vaginal, and udder surface temperatures in lactating cows exposed to heat stress (HS). In experiment 1, 12 multiparous and 8 primiparous Holstein cows experienced a THI ranging from 69 to 76 at 2000 to 1000 h and THI from 74 to 82 at 1000 to 2000 h (peaked at 82 from 1400 to 1800 h). Cows were exposed to HS 10 h daily for 21 d. Measurements of rectal temperature (RT) and udder surface temperature were collected at 1000 and 1500 h (±30 min). Vaginal temperature was monitored every 10 min using digital loggers, averaged over 1 h, and paired with corresponding rectal and udder surface temperature data. In experiment 2, 12 multiparous Holstein cows experienced a THI ranging from 60 to 76 at 2000 to 1000 h and THI from 69 to 83 at 1000 to 2000 h (peaked at 83 from 1600 and 1900 h), eliciting 10 h/d of HS for 7 d. Rectal and udder surface temperatures were analyzed at 0700 and 1500 h (±30 min). Vaginal temperature was recorded and analyzed as indicated in experiment 1. Afternoon THI showed weak correlations with surface temperature (r = 0.19, n = 420 in experiment 1; r = 0.23, n = 84 in experiment 2), weak to moderate correlations with RT (r = 0.34, n = 366 in experiment 1; r = 0.26, n = 84 in experiment 2), and moderate correlations with vaginal temperature (r = 0.34, n = 175 in experiment 1; r = 0.35, n = 40 in experiment 2). Moreover, vaginal temperature increased 0.10 and 0.22°C per unit of THI (R2 = 0.15 in experiment 1; R2 = 0.40 in experiment 2). Afternoon vaginal temperature strongly correlated with RT (r = 0.69, n = 131 in experiment 1; r = 0.63, n = 37 in experiment 2) and explained 57 (experiment 1) and 68% (experiment 2) of variation in RT. Surface temperature showed moderate to strong correlations with RT (r = 0.57, n = 84) and vaginal temperature (r = 0.74, n = 37) in experiment 2. In conclusion, THI showed a weak to moderate relationship with core body temperatures and explained the increase in rectal and vaginal temperatures experienced by HS cows. Compared with rectal temperature, vaginal temperature showed stronger relationships with THI and can be used to determine thermal load. Udder surface temperature showed a moderate to strong relationship with core body temperature, and this relationship may support the use of surface temperature data to manage thermal load in HS cows.

Short communication: A reproductive tract scoring system to manage fertility in lactating dairy cows.

We developed a reproductive tract size and position score (SPS) system as a reproductive management tool to identify lactating dairy cows with decreased fertility. This system, relying solely on transrectal palpation, considers the size (cervical and uterine) and position of the reproductive tract relative to the pelvis. Cows undergoing pre-breeding exams were identified as having reproductive tracts that were small (SPS1), medium (SPS2), or large (SPS3). Cows designated SPS1 had small and compact uterine horns that rested within the pelvic cavity; SPS2 cows had reproductive tracts that were intermediate in cervical and uterine horn diameter, with longer uterine horns resting partially outside the pelvic cavity; and SPS3 cows had reproductive tracts that were larger and rested mostly outside the pelvic cavity. Cows that were SPS1 had a higher rate of pregnancy per artificial insemination (43.3 ± 3.7%) than cows that were SPS2 (36.9 ± 3.6%) or SPS3 (27.7 ± 4.3%). The percentage of cows with an SPS2 score differed in pregnancies per artificial insemination compared with SPS3 cows. The average days in milk was similar for SPS1, SPS2, and SPS3 cows (104.3 ± 3.5, 98.4 ± 3.4, and 94.7 ± 7.7, respectively). Ultrasound measurements of the uterine horn and cervical diameter, and length measurements of the uterine horns, cervix, and vagina confirmed differences among the SPS groups derived by transrectal palpation. The ease with which transrectal palpation can be used to determine the size and position of the reproductive tract attests to the relevance and usefulness of this scoring system to identify less fertile lactating dairy cows. The ability to do so with ease provides an opportunity to make economically relevant management decisions and maximize reproductive efficiency in a given herd.

A polymorphism in XKR4 is significantly associated with serum prolactin concentrations in beef cows grazing tall fescue.

Fescue toxicosis is a common syndrome of poor growth and reproductive performance of beef cattle grazing endophyte-infected tall fescue infected with Lolium arundinaceum Schreb. Together with decreased feed intake, decreased growth rates and tissue necrosis due to vasoconstriction, depressed circulating serum prolactin concentrations are typically observed in cattle afflicted with fescue toxicosis. Polymorphisms within the XK, Kell blood group complex subunit-related family, member 4 (XKR4) gene located on BTA14 have been previously reported to be associated with rump fat thickness, residual feed intake, average daily feed intake and average daily gain in cattle. Associations also have been reported between XKR4 genotype and effectiveness of the dopamine antagonist iloperidone as a treatment of schizophrenia in humans. Domperidone, a related dopamine antagonist, mediates effects of fescue toxicosis on livestock, including restoring depressed concentrations of prolactin. A mixed-breed population of 592 beef cattle grazing endophyte-infected tall fescue was used to examine the association between XKR4 genotype and circulating prolactin concentrations. The SNP rs42646708 was significantly (P = 0.0002) associated with serum prolactin concentrations and explained 2.45% of the phenotypic variation. Effect of genotype at the SNP was tested across five breeds, with significant associations within both Angus (P = 0.0275) and Simmental (P = 0.0224) breeds. These results suggest XKR4 may play a role in mediating the negative effects of fescue toxicosis, and polymorphisms within this gene may be useful markers for selection for genetic resistance to the debilitating effects of endophyte-infected tall fescue.

Heat stress effects on the cumulus cells surrounding the bovine oocyte during maturation: altered matrix metallopeptidase 9 and progesterone production.

When the effects of heat stress are detrimental during maturation, cumulus cells are intimately associated with the oocyte. To determine the extent to which heat stress affects these cells, in this study, transcriptome profiles of the cumulus that surrounded control and heat-stressed oocytes (41 °C during the first 12 h only and then shifted back to 38.5 °C) during in vitro maturation (IVM) were compared using Affymetrix bovine microarrays. The comparison of cumulus-derived profiles revealed a number of transcripts whose levels were increased (n=11) or decreased (n=13) ≥ twofold after heat stress exposure (P<0.01), sufficient to reduce the development of blastocysts by 46.4%. In a separate study, quantitative PCR (qPCR) was used to confirm heat-induced differences in the relative abundances of the transcripts of five different genes (caveolin 1, matrix metallopeptidase 9, FSH receptor, Indian hedgehog homolog, and inducible nitric oxide synthase). Heat stress exposure resulted in >1.7-fold decrease in the protein levels of latent matrix metallopeptidase 9 (proMMP9). Heat-induced reductions in transcript levels were noted at 6 h IVM with reductions in proMMP9 protein levels at 18 h IVM (P=0.0002). Independent of temperature, proMMP9 levels at 24 h IVM were positively correlated with the development rate of blastocysts (R²=0.36; P=0.002). The production of progesterone increased during maturation; heat-induced increases were evident by 12 h IVM (P=0.002). Both MMP9 and progesterone are associated with the developmental competence of the oocyte; thus, it seems plausible for some of the negative consequences of heat stress on the cumulus-oocyte complex to be mediated through heat-induced perturbations occurring in the surrounding cumulus.

Evaluation of regional limb perfusion with erythromycin using the saphenous, cephalic, or palmar digital veins in standing horses.

There are no reported studies evaluating the use of erythromycin for regional limb perfusion (RLP) in horses. Our hypothesis was that using the cephalic and saphenous veins for RLP will enable delivery of therapeutic concentrations of erythromycin to the distal limb. Nineteen healthy horses participated in the study. The cephalic, saphenous or palmar digital (PD) vein was used to perfuse the limb with erythromycin. Synovial samples were collected from the metacarpo/metatarso-phalangeal (MCP/MTP) joint and blood samples were collected from the jugular vein. Maximum concentration (C(max)) of erythromycin in the MCP joint using the cephalic vein was 113 mg/L. The Cmax of erythromycin in the MTP joint using the saphenous vein was 38 mg/L. Erythromycin administered using the PD vein was not detectable in the MCP/MTP joint of four of six horses. Concentrations of erythromycin achieved in the synovial fluid of the MCP/MTP joint were between 152 and 452 times the minimal inhibitory concentration (MIC) for Rhodococcus equi (R. equi). In conclusion, the results indicate that when using the saphenous or cephalic veins for RLP, therapeutic concentrations of erythromycin in the MCP/MTP joint can be consistently reached [corrected].

Evaluation of regional limb perfusion with amikacin using the saphenous, cephalic, and palmar digital veins in standing horses.

Previous studies have shown that regional limb perfusion (RLP) using the palmar digital (PD) vein delivers therapeutic concentration of amikacin to the distal limb. Our hypothesis was that using the cephalic and saphenous veins for RLP will enable delivery of therapeutic concentrations of amikacin to the distal limb. Nineteen healthy horses participated in the study. The cephalic, saphenous, or PD vein was used to perfuse the limb with amikacin. Two grams of amikacin was used for RLP using the saphenous and the cephalic veins, and one gram was used in the PD vein. Synovial samples were collected from the metacarpo-/metatarsophalangeal (MCP/MTP) joint, and blood samples were collected from the jugular vein. Maximum concentration (Cmax) of amikacin in the MCP/MTP joint using the cephalic and the saphenous vein was 277 and 363 mg/L, respectively. The amikacin concentrations achieved in the synovial fluid of the MCP/MTP joint in the current study were between 69 and 91 times the minimally inhibitory concentration of common susceptible bacterial pathogens causing orthopedic infections in horses. To conclude, this study shows that use of the proximal veins for RLP to treat distal limb infections is a viable alternative to using the palmar or plantar digital vein.

Short communication: Evaluation of bulk tank milk microbiological quality of nine dairy farms in Tennessee.

The purpose of this study was to evaluate the bulk tank milk (BTM) quality of 9 East Tennessee dairy farms and to determine its relationship with selected quality milk parameters. Bulk tank milk samples (n=1,141) were collected over a 42-mo period (June 2006 through November 2009) from farms, based on their preliminary incubation count (PIC) history. Parameters of BTM quality evaluated in this study included somatic cell count (SCC), standard plate count (SPC), PIC, laboratory pasteurization count (LPC), Staphylococcus spp. count, Streptococcus spp. count, and coliform count. Strong correlations between SPC and Streptococcus spp. counts (0.72) and between SPC and PIC (0.70) were found. However, moderate correlations were seen among other milk quality parameters. In addition, seasonal variations for some milk quality parameters were noted. For example, milk quality parameters such as SCC, SPC, LPC, and coliform count were significantly higher in summer, whereas Streptococcus spp. counts were significantly higher in winter. No seasonal variation in PIC or Staphylococcus spp. counts was observed. Summarizing, results from this investigation showed the importance of using several bacterial counts (SCC, SPC, PIC, LPC, Streptococcus spp. count, Staphylococcus spp. count, and coliform counts) as simultaneous indicators of milk quality.

Disparate consequences of heat stress exposure during meiotic maturation: embryo development after chemical activation vs fertilization of bovine oocytes.

Consequences of heat stress exposure during the first 12 h of meiotic maturation differed depending on how and when bovine oocytes were activated. If heat-stressed oocytes underwent IVF at ~24 h, blastocyst development was less than for respective controls and similar to that obtained for nonheat-stressed oocytes undergoing IVF at 30 h (i.e. slightly aged). In contrast, if heat-stressed oocytes underwent chemical activation with ionomycin/6-dimethylaminopurine at 24 h, blastocyst development was not only higher than respective controls, but also equivalent to development obtained after activation of nonheat-stressed oocytes at 30 h. Developmental differences in chemically activated vs IVF-derived embryos were not related to fertilization failure or gross alterations in cytoskeletal components. Rather, ionomycin-induced calcium release and MAP kinase activity were less in heat-stressed oocytes. While underlying mechanisms are multifactorial, ability to obtain equivalent or higher development after parthenogenetic activation demonstrates that oocytes experiencing heat stress during the first 12 h of meiotic maturation have the necessary components to develop to the blastocyst stage, but fail to do so after fertilization.

Developmental competence of bovine embryos from heat-stressed ova.

Because multiple ovulation embryo transfer procedures are occasionally performed in cows experiencing heat stress, the goal of this study was to assess the developmental competence of otherwise morphologically normal embryos from heat-stressed ova. To this end, the ability of compact morulae from heat-stressed and non-heat-stressed bovine ova to undergo blastocyst development after culture at 38.5 or 41.0 degrees C was examined. It was hypothesized that heat-induced perturbations in the ooplasm carry over to increase the susceptibility of the preattachment embryo to heat stress. Initially, ova were matured at 38.5 or 41.0 degrees C. The consequences of heat stress did not include altered cleavage, but did reduce the proportion of 8- to 16-cell-stage embryos (55.3 vs. 50.6%; SEM +/- 1.9). Although proportionately fewer, compact morulae from heat-stressed ova were equivalent in quality to those from non-heat-stressed ova (2.1 and 2.1; SEM = 0.04). Culture of compact morulae from non-heat-stressed ova at 41.0 degrees C did not affect blastocyst development (71.9 and 71.5%; SEM = 3.0). Furthermore, the development of compact morulae from heat-stressed ova was similar to that of non-heat-stressed ova after culture at 38.5 degrees C (68.2 vs. 71.9 and 71.5%; SEM = 3.0). However, blastocyst development was reduced when compact morulae from heat-stressed ova were cultured at 41.0 degrees C (62.3 vs. 71.9, 71.5 and 68.2; SEM = 3.1). In summary, reduced compaction rates of heat-stressed ova explained in part why fewer develop to the blastocyst stage after fertilization. The thermolability of the few embryos that develop from otherwise developmentally challenged ova emphasizes the importance of minimizing exposure to stressor(s) during oocyte maturation.

Evaluation of indwelling intravenous catheters for the regional perfusion of the limbs of horses.

The feasibility of maintaining indwelling intravenous catheters in the saphenous, cephalic or palmar digital vein of horses for seven days to infuse antimicrobial drugs was investigated in 18 horses. The horses were randomly assigned to six groups according to the vein catheterised and whether they received amikacin or erythromycin. None of the catheters was replaced more than once, and 11 of the 18 catheters remained patent for all seven days. Neither the drug administered nor the vein catheterised significantly affected the survival of the catheter. In all but three cases, complications, including local inflammation, lameness, thrombophlebitis and one severe tissue reaction to erythromycin, resolved during the seven days.

Evaluation of dimethyl sulphoxide effects on initial response to endotoxin in the horse.

REASONS FOR PERFORMING STUDY: Endotoxaemia is one of the most severe and ubiquitous disease processes in horses. Although dimethyl sulphoxide (DMSO) is used clinically in horses, there is no study indicating its efficacy in endotoxaemic horses. HYPOTHESIS: DMSO ameliorates the clinical response to i.v. lipopolysaccharide (LPS) administration. METHODS: Eighteen horses were assigned randomly to one of 4 groups: Normosol-LPS (0.2 mug/kg bwt, i.v.); DMSO (1 g/kg bwt, i.v.)-saline; high-dose DMSO (1 g/kg bwt, i.v.)LPS; low-dose DMSO (20 mg/kg bwt, i.v.)-LPS. Horses participating in the DMSO-saline group were later assigned randomly to one of the LPS groups. Data for physical parameters, white blood cell counts, plasma TNF-alpha, and blood lactate and glucose concentrations were examined for the effect of treatment using a repeated-measures mixed-model ANOVA. A value of P<0.05 was considered significant. RESULTS: Endotoxaemia occurred in all horses receiving LPS, as indicated by the clinical score, physical parameters, haemoconcentration and leucopenia. High-dose DMSO ameliorated the effect of LPS on fever. DMSO, at either dose, but did not have a significant effect on LPS-induced changes in all other evaluated parameters. CONCLUSIONS: In this study, DMSO had minimal effects on clinical signs of induced endotoxaemia in horses. The effects were manifested by amelioration of LPS-induced fever.

In vitro effects of hydrochloric and lactic acids on bioelectric properties of equine gastric squamous mucosa.

REASONS FOR PERFORMING STUDY: Volatile fatty acids, byproducts of carbohydrate fermentation by resident bacteria, have been implicated in causing nonglandular (NG) gastric ulcers. Lactic acid (LA), also produced by stomach bacteria, may cause gastric ulcers when exposed to the equine NG mucosa. OBJECTIVES: To investigate the in vitro effects of LA on equine NG mucosa bioelectric properties, sodium transport and tissue resistance. METHODS: Gastric tissues obtained from 13 mature horses were studied in Ussing chambers. Short-circuit current (Isc) and potential difference (PD) were measured, and electrical resistance (R) and conductance (G) calculated for tissues after addition of HCl and LA (5, 10, 20 and 40 mmol/l) in normal Ringer's solution (NRS). RESULTS: Mucosa exposed to HCl or LA (5, 10 and 20 mmol/l) in NRS (pH 1.5 and to a lesser extent pH 4.0) had a significant decrease in Isc and PD. Mucosa exposed to a high concentration of LA (40 mmol/l) in NRS (LRS) at pH 1.5 showed an increased G, but this increase was not significant. Values returned to baseline after solutions were returned to pH 7.0. Histological changes were consistent with HCl-induced (pH <4.0) acid damage. CONCLUSIONS: HCl induced alteration in bioelectric properties of equine NG mucosa whereas addition of LRS did not, other than those changes seen with HCl alone.

Manipulation of thyroid status and/or GH injection alters hepatic gene expression in the juvenile chicken.

Both thyroid hormone (T3) and growth hormone (GH) are important regulators of somatic growth in birds and mammals. Although T3-mediated gene transcription is well known, the molecular basis of T3 interaction with GH on growth and development of birds remains unknown. In earlier studies, we discovered that exogenous GH alone increased accumulation of visceral fat in young chickens, while the combination of GH injections and dietary T3 worked synergistically to deplete body fat. In the present study, cDNA microarray and quantitative RT-PCR analyses enabled us to examine hepatic gene expression in young chickens after chronic manipulation of thyroid status and GH injection alone or in combination with T3. Thyroid status modulates expression of common and unique sets of genes involved in a wide range of molecular functions (i.e., energy metabolism, storage and transport, signal transduction, protein turnover and drug detoxification). Hepatic expression of 35 genes was altered by hypothyroidism (e.g., ADFP, ANGPTL3, GSTalpha, CAT, PPARG, HMGCL, GHR, IGF1, STAT3, THRSPalpha), whereas hyperthyroidism affected expression of another cluster of 13 genes (e.g., IGFBP1, KHK, LDHB, BAIA2L1, SULT1B, TRIAD3). Several genes were identified which have not been previously ascribed as T3 responsive (e.g., DEFB9, EPS8L2, ARHGAP1, LASS2, INHBC). Exogenous GH altered expression of 17 genes (e.g., CCAR1, CYP2C45, GYS2, ENOB, HK1, FABP1, SQLE, SOCS2, UPG2). The T3+GH treatment depleted the greatest amount of body fat, where 34 differentially expressed genes were unique to this group (e.g., C/EBP, CDC42EP1, SYDE2, PCK2, PIK4CA, TH1L, GPT2, BHMT). The marked reduction in body fat brought about by the T3+GH synergism could involve modulation of hormone signaling via altered activity of the Ras superfamily of molecular switches, which control diverse biological processes. In conclusion, this study provides the first global analysis of endocrine (T3 and GH) regulation of hepatic gene transcription in the chicken.

Early in vitro fertilization improves development of bovine ova heat stressed during in vitro maturation.

The objectives were to examine the development of embryos derived from control (38.5 degrees C) or heat-stressed ova [41.0 degrees C during the first 12 h of in vitro maturation (hIVM)] when in vitro fertilization (IVF) was performed at 16, 18, 20, 24, or 30 hIVM. Effects of heat stress in compromising ovum development depended on when IVF was performed (in vitro maturation temperature x IVF time interaction). When IVF was performed at 24 or 30 hIVM, fewer heat-stressed ova developed to the blastocyst stage compared with the respective controls. In contrast, when IVF was performed at 16, 18, or 20 hIVM, more heat-stressed ova developed to the blastocyst stage compared with the respective controls. Performing IVF earlier than usual was beneficial, because the ability of heat-stressed ova to develop to the blastocyst stage was improved when IVF was performed at 18 or 20 vs. 24 hIVM. Blastocyst stage and quality were equivalent to non-heat-stressed controls regardless of IVF time. Control ova undergoing IVF at 20, 24, 30, or 32 hIVM and heat-stressed ova undergoing IVF at 16, 18, 20, or 24 hIVM were compared for blastocyst development by multisource regression. Although linear and quadratic slopes were similar, heat stress reduced the peak and shifted the developmental response of ova by 7.3 h. In other words, obtaining optimal blastocyst development from heat-stressed ova would depend on performing IVF at 19.5 hIVM compared with 26.7 hIVM for non-heat-stressed controls. Heat-induced reductions in peak blastocyst development significantly reduced the window of time available to perform IVF and obtain > or = 20% blastocyst development. In summary, results support an effect of heat stress to hasten developmentally important events during oocyte maturation. The inability of earlier IVF to fully restore the development of heat-stressed ova to that of non-heat-stressed controls highlights the importance of further study.

Effects of a concentrated lidocaine solution on the acute phase stress response to dehorning in dairy calves.

The objective of this study was to more fully define the surgical stress response to dehorning by heat cauterization in dairy calves by measuring behavioral, hormonal, inflammatory, and immunological markers of stress and to determine whether a nerve block of the surgical site with a concentrated solution of lidocaine (5%) reduces the degree of stress. Thirty-two 10- to 12-wk-old female Holstein calves were randomly allotted to 1 of 4 treatments: 5% lidocaine followed by dehorning, 2% lidocaine followed by dehorning, saline followed by dehorning, or 5% lidocaine followed by sham dehorning. Plasma cortisol concentration was measured in blood samples collected via a jugular catheter at -0.5, 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 9, 12, 24, 48, and 72 h. Various other blood constituents were measured in samples collected at -0.5, 12, 24, 48, and 72 h. Feeding, drinking, scratching, grooming, rubbing, licking, and inactivity behaviors were observed in the standing and recumbent positions using a 10-min scan sampling method analyzed on a time period and daily basis for 72 h following the dehorning procedure. The frequency of vocalization, kicking, and lying in the chute during the dehorning procedure were also assessed. The overall plasma cortisol concentrations were higher in calves subjected to dehorning than in control calves. Compared with the control group, the saline-treated calves had a higher cortisol concentration at 30 and 60 min postdehorning. Plasma cortisol concentrations were higher in all groups at 30 min postdehorning than at other sampling times. The percentage of circulating neutrophils and the neutrophil:lymphocyte ratio were increased in the saline and 2% lidocaine group. Total plasma protein, fibrinogen, and alpha1-acid glycoprotein concentrations were similar among treatments. The behavioral response to dehorning, as manifested by kicking while in the chute, was greater in the saline and 2% lidocaine group than in the control or 5% lidocaine treatment groups. In the postdehorning period, the percentage of time calves spent performing various maintenance behaviors did not differ among treatments. Thus, injection of 5% lidocaine may not provide any added comfort after the dehorning but may decrease the overall stress response during the procedure.

Use of fetal fibronectin in the management of preterm labour in Nunavut.

OBJECTIVES: To manage suspected preterm labour in the Baffin Region of Nunavut safely and more conservatively utilizing the Fetal Fibronectin Assay. STUDY DESIGN: Chart Review. METHODS: The trial of Fetal Fibronectin took place in the Baffin Region of Nunavut. An initial chart review of all admissions for "false labour" to Baffin Regional Hospital was performed. An analysis of the cases was done to determine when the women delivered and whether they had been Medevaced. The Fetal Fibronectin test was implemented at five sites in the Baffin Region and data on each use of the assay were collected by the laboratory at Baffin Regional Hospital. A review of the data for the first 13 months of the trial was then done. RESULTS: The test was used 38 times between July 2004 and September 2005. There were 31 negative results. Most of the cases with negative results were managed conservatively, with a total of 18 Medevacs avoided. There were no false negative tests. Cost savings for avoided Medevacs were in the order of $200,000. CONCLUSIONS: The Fetal Fibronectin Assay has proven to be a valuable adjunct in the management of suspected preterm labour in Nunavut.

Relationships among temperament, acute and chronic cortisol and testosterone concentrations, and breeding soundness during performance testing of Angus bulls.

The aim of this study was to examine relationships among temperament, endocrinology, and reproductive parameters of bulls enrolled in an 84-day performance test. Angus bulls (n = 60) were housed in six pens grouped by age and weight. Pen scores (PS; 1 = docile to 5 = very aggressive) were assigned on Days -1, 27, 55, and 83 of the performance test. On the following day, blood and hair samples were collected, and body weight (BW) and exit velocity (EV) were recorded. Bulls were split into two categories based on; Day -1 PS (PScalm = PS 1 or 2; PSexcitable = PS 3 or 4) and Day 0 EV (EVcalm = slowest 20 bulls; EVexcitable = fastest 20 bulls). Cortisol and testosterone concentrations in serum and hair did not differ (P > 0.10) between PS or EV temperament categories. Sampling day differences (P < 0.01) occurred for serum testosterone, hair cortisol, and hair testosterone concentration; however, serum cortisol concentration did not differ (P > 0.10) over the sampling days. Serum testosterone concentration increased (P < 0.01) from Day 0 to 28, decreased from Day 28 to 56, but Day 84 did not differ from Day 0, 28, or 56. Hair cortisol concentration was greatest (P < 0.01) on Day 0, decreased from Day 28 to 56 but did not differ from Day 56 to 84. Hair testosterone concentration was greatest (P < 0.01) on Day 0 and remained constant from Day 28 to 84. Bulls categorized as PScalm had a greater (P < 0.01) percentage of normal sperm and secondary defects (P < 0.01) when compared with PSexcitable bulls. However, EVcalm bulls had fewer (P < 0.01) primary defects but more (P < 0.01) secondary defects than EVexcitable bulls. In conclusion, bulls exhibited physiological evidence of acclimation during the test as indicated by a reduction in hair cortisol concentration. In addition, the ability of the bulls to acclimate while residing at the testing center may have contributed to little differences observed during the breeding soundness examination portion of the performance test.

Management of native warm-season grasses for beef cattle and biomass production in the Mid-South USA.

Native grasses, such as switchgrass (SG; L.), big bluestem (BB; Vitman), indiangrass (IG; Nash), and eastern gamagrass (EG; [L.] L.) may be capable of providing desirable summer forage for cattle as well as a source of biomass for renewable energy. To evaluate that potential, experiments were conducted at 2 locations in Tennessee comparing weaned beef () steers (268 ± 25 kg initial BW) during early-season grazing (Early; 30 d, typically corresponding to May, followed by postdormancy biomass harvest) and full-season grazing (Full, mean duration = 98 d). For Exp. 1, which compared SG, a blend of BB and IG (BBIG), and EG, ADG was greater ( < 0.05) for BBIG (1.02 kg/d) than SG (0.85 kg/d), and both were greater ( < 0.05) than EG (0.66 kg/d). Grazing days for SG and EG were similar (389 and 423 animal unit days [AUD]/ha, respectively) and exceeded ( < 0.05) that of BBIG (233 AUD/ha) during Full. In Exp. 2 (SG and BBIG only), rates of gain were comparable to that of Exp. 1, but AUD were 425 (SG) and 299 (BBIG) AUD/ha. Such rates of gain and grazing days indicate that these grasses can provide desirable summer forage for growing cattle. Early produced 211 to 324 kg BW gain/ha, depending on experiment and forage, followed by dormant-season harvests of 7.5 to 10.5 Mg/ha of biomass, indicating a potential for beef cattle forage and biomass production on the same land resource. Native grasses provided productive summer pasture and good rates of gain on growing cattle and could contribute to forage programs, especially where cool-season grasses currently predominate.

Pronurturance Plus at birth: A risk reduction strategy for preventing postpartum haemorrhage.

BACKGROUND: Postpartum haemorrhage (PPH) rates continue to rise in the developed world. A recent study found that any skin-to-skin contact and breastfeeding within 30min of birth was associated with an almost 50% reduction in PPH rates. Improved oxytocin release is the biological reason proposed to explain this. The combination of skin-to-skin contact and breastfeeding within 30min of birth is termed 'Pronurturance'. Midwifery theory and research claims that optimal third stage care is more holistic than simple Pronurturnace which suggests that further reductions in PPH rates may be possible. QUESTION: What can midwives and women do to minimise blood loss in the third and fourth stages of labour? METHOD: We present a new theory that describes and explains how to optimise the woman's reproductive psychophysiology in the third and fourth stages of labour to ensure a well contracted uterus which inhibits excessive bleeding regardless of risk status or whether active management was used. In developing the Pronurturance Plus theory we expand upon what is already known about oxytocin in relation to simple pronurturance to integrate concepts from birth territory theory, cognitive neuroscience, mindfulness psychology and the autonomic nervous system to develop an holistic understanding of how to optimise care and minimise PPH. CONCLUSION: Pronurturance Plus is a psycho-biologically grounded theory which is consistent with existing evidence. It is free, natural and socially desirable.