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Simple Summary: Tail docking and castration are common procedures performed in lambs but are considered painful. Mitigation of the pain associated with these procedures is difficult, especially when using rubber ring castration. The objectives of this study were to compare castration and tail docking efficacy between lidocaine-impregnated ligation bands (LLBs) and control bands (CBs) under field conditions and identify the benefits of pain control provided by LLBs. In this study, 238 male lambs were randomly assigned to receive either LLBs or CBs on both their tail and scrotum. CBs and LLBs were both 100% effective with respect to casting success of the tail and scrotum. Lambs receiving LLBs gained more weight from d −3 to 7 following application, which may be an indication of pain control during the first week following band application. However, there were no differences observed in average daily gain over the entire study period. The primary objective of this study was to demonstrate the non-inferiority between lidocaine-impregnated ligation bands (LLBs) and control bands (CBs) with respect to the efficacy of castration and tail docking. Secondary objectives were to compare castration and tail-docking success, evaluate local site reactions, and compare average daily gain (ADG) between the treatment groups. A total of 238 male lambs were enrolled and randomly assigned to receive LLBs or CBs on their tail and scrotum. Lambs were weighed, had a health assessment, and the band site was observed on −3, 7, 14, 21, 28, 35, and 42 days after the bands were applied. A linear regression model was built to assess average daily gain, whereas a repeated measures model was used to evaluate body weight differences at each of the measured timepoints. Furthermore, logistic regression models were used to evaluate associations with casting outcomes. Few differences were noted between treatment groups with respect to casting success for the scrotum and tail and ADG over the entire experimental period. Non-inferiority calculations demonstrated no differences in tail docking and scrotal casting success, with casting occurring for the majority of animals by d 21 and d 42 for castration and tail docking, respectively. However, lambs receiving LLBs gained more weight from d −3 to 7 (+0.03 kg/d; 95% CI: 0 to 0.07), which may be an indication of effective pain control during the first week following band application. Overall, the use of an LLB does not affect the time to successful casting of the tail and could improve short-term growth when compared to a control band. Further studies are needed to compare LLBs to multimodal methods of pain relief. [ABSTRACT FROM AUTHOR]

Simple Summary: Castration is commonly performed in young dairy calves and results in pain and discomfort. This study aimed to assess the effective tissue concentrations of the current standard of care for pain mitigation in calves during castration (injectable lidocaine) and to assess the ability of lidocaine-loaded bands (LLBs) to deliver effective concentrations into the scrotal tissue over time. The injectable lidocaine provided effective anesthesia for up to 60 min, highlighting the importance of finding additional strategies to manage long-term pain. A ligation band impregnated with lidocaine could provide a suitable alternative, as it appears to deliver effective lidocaine concentrations starting as early as 2 h following application and lasting at least 28 days after application. Further studies are warranted to compare the use of LLBs to injectable local anesthetics. This study aimed to assess the effective tissue concentrations of the current standard of care for pain mitigation in calves during castration (injectable lidocaine) and to assess the ability of a lidocaine-loaded elastration band (LLB) to deliver effective concentrations into the scrotal tissue over time. This study comprised two different trials: (1) effective concentrations of injectable lidocaine in the scrotal tissue; and (2) the in vivo delivery of effective concentrations of lidocaine from LLBs placed on the calf scrotums. Sensation in the scrotal tissue was assessed by electrocutaneous stimulation. Injectable lidocaine allowed for short-term anesthesia for up to 60 min, highlighting the importance of finding additional strategies to mitigate long-term pain. An elastomeric ligation band impregnated with lidocaine could provide a suitable alternative, as it yielded tissue levels of lidocaine that approached EC50 and exceeded EC95 at 2 and 72 h following application, respectively, and remained above those levels for at least 28 days after application. Further studies are warranted to compare the use of LLBs to injectable local anesthetics. [ABSTRACT FROM AUTHOR]

Simple Summary: In most high-income countries, piglets undergo certain elective surgical procedures such as castration and tail docking to eliminate behaviors that are associated with mortality and the condemnation of animals and meat. It has been well established that both castration and tail docking are both painful, yet there are limited products for addressing short-term and long-term pain. Lidocam™ Topical Gel (LTG) (4% lidocaine and 0.3% meloxicam) was developed to address the animal welfare and production requirements of the swine industry. The studies described in this paper show that applications of LTG to the scrotal area and tail base act to control the pain associated with these surgical procedure. The studies also demonstrate that LTG was able to control pain and inflammation at the surgical sites for at least 24 h after application. This was demonstrated by using established physiological and behavioral markers for surgical pain: plasma cortisol and substance P, vocalization during procedure, electrocutaneous stimulation of surgical site, and body weight gain. LTG is potentially an effective product for controlling pain and inflammation for use in castration and tail docking in piglets. (1) Background: It has been well established that castration and tail docking are both painful during and following the procedure, yet there are limited convenient and effective products to address both short-term and long-term pain. Lidocam Topical Gel (LTG) (4% lidocaine and 0.3% meloxicam) was developed to address industry needs for an effective and safe product to address animal welfare concerns regarding castration and tail docking in piglets. (2) Methods: Study 1: Male piglets aged 4–8 days of age were treated with LTG (n = 30) or a control gel (n = 30). Approximately 30 min after application of the gel, the piglets were surgically castrated and tail docked. The efficacy of pain control during the surgical procedures and post-procedure (24 h) pain and inflammation control were evaluated using both behavioral and physiological measurements. Study 2: Meloxicam residue depletion following LTG treatment was followed for 28 days. Study 3: Clinical and pathological safety were evaluated in five groups of eight piglets receiving LTG with: (1) no treatment, (2) nominal topical dose, (3) two times the nominal topical dose, (4) three times the nominal topical dose, and 5) one times the nominal topical dose and 2 mL of LTG by oral gavage daily for 3 days. (3) Results: LTG-treated piglets had a significant reduction in electrocutaneous stimulation response before the procedures and 4 and 24 h post-procedures. Stress vocalization intensity and duration were less in piglets receiving LTG during the surgical procedures. Plasma cortisol and substance P were significantly lower in LTG-treated piglets 3 h after castration and tail docking. The weight and average daily gain were significantly increased in piglets receiving LTG. LTG did not interfere with wound healing or cause irritation at the application sites. There were no abnormal clinical or pathological findings associated with the use of LTG at three times the nominal dose given daily for three days. As meloxicam persisted in the application site tissue, a slaughter withdrawal time of 24 days was determined. (4) Conclusions: When applied to the skin 30 min before castration and tail docking, LTG is effective in surgical pain control and provides post-surgical pain control for up to 24 h. LTG is safe for use in piglets and provides an acceptable withdrawal time for commercial use. LTG is a potentially effective product for commercial use for piglet castration and tail docking. [ABSTRACT FROM AUTHOR]

Food-borne pathogens are a serious challenge in food handling, processing, and packaging systems. The growth of microbial biofilms on food handling surfaces further complicates the management of the microbial contamination of food. Microorganisms within biofilms are difficult to eradicate with chemical disinfectants, with an increased likelihood of survival and the subsequent contamination of food. Therefore, a biofilm approach is needed in food safety and hygiene studies. Since many factors, such as strain, cell density, surface type and texture, environmental stress, and so forth, can affect biofilm formation and disinfectant efficacy, we evaluated the responses of biofilms formed by three food-borne bacterial pathogens on eight hard surfaces to seven chemical disinfectants. The three bacteria showed different capacities to colonize the surfaces. Similarly, chemical disinfectants also varied in efficacy, on surfaces and with pathogen species. One-, two-, and three-way interactions of strain, surface, and disinfectant were observed. The results generated demonstrate that the fine-tuning of sanitization strategies along the food production, processing, and packaging chain can be achieved in specific scenarios by accounting for two- and three-way interactions among bacteria, surface, and disinfectant. [ABSTRACT FROM AUTHOR]

The development of novel antimicrobial technologies for the food industry represents an important strategy to improve food safety. Antimicrobial photodynamic disinfection (aPDD) is a method that can inactivate microbes without the use of harsh chemicals. aPDD involves the administration of a non-toxic, light-sensitive substance, known as a photosensitizer, followed by exposure to visible light at a specific wavelength. The objective of this study was to screen the antimicrobial photodynamic efficacy of 32 food-safe pigments tested as candidate photosensitizers (PSs) against pathogenic and food-spoilage bacterial suspensions as well as biofilms grown on relevant food contact surfaces. This screening evaluated the minimum bactericidal concentration (MBC), minimum biofilm eradication concentration (MBEC), and colony forming unit (CFU) reduction against Salmonella enterica, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas fragi, and Brochothrix thermosphacta. Based on multiple characteristics, including solubility and the ability to reduce the biofilms by at least 3 log10 CFU/sample, 4 out of the 32 PSs were selected for further optimization against S. enterica and MRSA, including sunset yellow, curcumin, riboflavin-5′-phosphate (R-5-P), and erythrosin B. Optimized factors included the PS concentration, irradiance, and time of light exposure. Finally, 0.1% w/v R-5-P, irradiated with a 445 nm LED at 55.5 J/cm2, yielded a "max kill" (upwards of 3 to 7 log10 CFU/sample) against S. enterica and MRSA biofilms grown on metallic food contact surfaces, proving its potential for industrial applications. Overall, the aPDD method shows substantial promise as an alternative to existing disinfection technologies used in the food processing industry. [ABSTRACT FROM AUTHOR]

Simple Summary: Tail docking and castration in lambs are common husbandry practices, both of which cause pain and discomfort, for which many industries recommend or require pain management. The objectives of this study were to assess the effects of the current standard-of-care for pain mitigation in lambs (injectable lidocaine) and assess the ability of a lidocaine-impregnated elastration ligation band to deliver the drug into the contacted tissues over time. The use of injectable lidocaine provides effective short-term anesthesia for 120 to 180 min following the injection; however, additional strategies are needed to manage long-term pain. The use of a ligation band impregnated with lidocaine could provide a useful alternative, as it appears to offer local anesthesia for at least 3 days when compared to a control band. Further studies are needed to compare the use of an injectable local anesthetic to the Lidocaine-Loaded Bands (LLBs). The objectives of this study were to assess the pharmacokinetics and pharmacodynamics of the current standard-of-care for pain mitigation in lambs during castration and tail docking (injectable lidocaine) and assess the ability of Lidocaine-Loaded Bands (LLBs) to deliver therapeutic concentrations into the contacted tissues over time. The study was comprised of four different trials: (1) investigation of in vitro release of lidocaine from LLBs; (2) pharmacokinetics and pharmacodynamics of injectable lidocaine in scrotal and tail tissue; (3) pharmacokinetics and pharmacodynamics of in vivo delivery of lidocaine with LLBs placed on the tail and scrotum of lambs; and (4) a "proof-of-concept" study comparing the sensation of control- versus LLB-banded tail tissue over time. The use of injectable lidocaine provides effective short-term anesthesia for 120 to 180 min following the injection; however, additional strategies are needed to manage long-term pain. The use of an LLB could provide an alternative where tissue lidocaine concentrations meet or exceed the EC50 for at least 21–28 days and, based on electrostimulation data, provides local anesthesia for at least 3 days when compared to a control band. Further studies are needed to compare the use of an injectable local anesthetic to the LLBs. [ABSTRACT FROM AUTHOR]

Tail docking in lambs and castration in lambs and calves are common husbandry practices, both of which cause pain and discomfort, for which many industries recommend or require pain management. The purpose of this study was to assess the effective tissue concentrations of the current standard of care for pain mitigation in calves and lambs during castration or tail docking (injectable lidocaine) and to assess the ability of a lidocaine-loaded elastration band (LLB) to deliver effective concentrations into the scrotal or tail tissues over time. This work comprised four different field trials (n = 50/trial): 1) effective concentrations of injectable lidocaine in the scrotal tissue of dairy calves; 2) the in vivo delivery of effective concentrations of lidocaine from LLBs placed on the calf scrotums; 3) effective concentrations of injectable lidocaine in the scrotal and tail tissue of lambs; and 4) the in vivo delivery of effective concentrations of lidocaine from LLBs placed on the lamb scrotums and tails. Sensation in the tissue of interest was assessed by electrocutaneous stimulation. Sensation was correlated to tissue concentrations of lidocaine by analyzing sampled tissue for lidocaine content by High-Performance Liquid Chromatography (HPLC). Injectable lidocaine allowed for short-term anesthesia for up to 60 min calves, highlighting the importance of finding additional strategies to mitigate long-term pain. An effective concentration (EC) yielding 50% reduction in tissue sensation (EC50) of 0.635 (95% CI 0.462 to 0.829) mg/g was calculated for calf scrotal tissue. Based on HPLC data of processed biopsy samples taken over time, the LLBs yielded tissue concentartions of lidocaine that approached EC50 and exceeded EC95 at 2 and 72 h following application, respectively, and remained above those concentartions for at least 28 d after application. In lambs, injectable lidocaine allowed for short-term anesthesia for up to 180 min following injection. An EC50 of 0.174 (95% CI 0.125 to 0.248) mg/g was calculated for lamb scrotal tissue and an EC50 of 0.0765 (95% CI 0.0533 to 0.113) mg/g was calculated for lamb tail tissue. The use of the LLB provided tissue lidocaine concentrations that met or exceeded the EC50 for at least 21 to 28 d and, based on electrostimulation data, provided local anesthesia for at least 3 d when compared with a control band. The use of an LLB could provide a practical, longduration alternative to injectable lidocaine for pain mitigation during castration and tail docking. Further studies are warranted to compare the use of LLBs to injectable local anesthetics. [ABSTRACT FROM AUTHOR]

Simple Summary: Impact of dystocia on milk production, somatic cell count, reproduction and culling in Holstein dairy cows. By Roche et al. The objective of this study was to explore the impact that dystocia had on future health and productivity of dairy cows. Data from 2159 cows from 21 different dairy farms in Alberta were collected and analyzed. We found that cows with a moderate to high level of assistance produced less milk over their lactation and were more likely to be culled from the herd, whereas cows with an easy pull produced less milk fat and were more likely to have a retained placenta. This study investigated the effects of dystocia on milk production, somatic cell count, reproductivity, disease, and milk production. A total of 2159 cows across 21 dairy farms in Alberta, Canada were enrolled in this study. Multivariable models were created to explore associations between outcome variables and calving ease score. In total, 89.5% of calvings were unassisted, 6.1% were an easy pull, and 4.3% were a moderate–hard pull. Cows that had a moderate–hard pull produced 4.01 kg less milk, 0.12 kg less volume of milk fat, and 0.12 kg less milk protein per day than those that had an unassisted calving. No difference was found between calving ease groups with respect to SCC. Cows with a moderate or hard pull produced 510 kg less milk per lactation than unassisted cows. Cows with a moderate to high level of assistance at birth had a higher hazard of being culled over the duration of their lactation. Cows with an easy pull had increased odds of developing a retained placenta. It is evident that assistance at calving, particularly a moderate–hard pull, is associated with significant impacts on future milk production and risk of being culled; therefore, efforts should be made to minimize dystocia and prevent these impacts. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate an easy to administer and economical oral nutritional supplement for neonatal lambs. Neonates are at risk of nutrient deficiencies because of maternal deficiencies, minimal body stores at birth and decreased nutritional intake. The pre-ruminant lamb relies solely on milk for adequate immunity and nutrition until they begin ingesting forages. Insufficiencies can lead to increased mortality and morbidity. However, deficiencies in the ewe are common due to variation in management, feeding and health protocols. A total of 10 lambs (5 sets of twins) were enrolled into the study. The lambs were divided into two groups (one twin from each set) received a treatment of an oral vitamin-mineral supplement (VitaFerst-Care) 3 mL and the control lambs a saline solution of 3 mL, all at 3 d of age (d0). Blood samples were collected, prior to, and again following supplementation (d 0, d 21) by jugular venipuncture. Vitamin A, vitamin E, iron (Fe) and selenium (Se) concentrations were determined in blood serum/plasma of the lambs by HPLC. Kidney and liver function markers were analyzed using HESKA DC5X veterinary analyzer to confirm the safety of the supplement. Variables tested included alkaline phosphatase (ALP), alanine aminotransferase (ALT), blood urea nitrogen (BUN), creatinine (CREA), glucose (GLU), total protein (TP), total bilirubin (T-BILI), albumin (ALB), phosphorus (PHOS), calcium (CA), cholesterol (CHOL), and gamma-glutamyl transferase (GGT). All lambs remained with their mothers. The average difference was calculated between d 21 and d 0 (baseline) for treated versus control animals for vitamin A, vitamin E, Se, and Fe. Significance was calculated using a two-tailed student’s t-test where P < 0.10 between d 21 control and treated animals. Control animals had an average vitamin E plasma concentration of 1.168 + 0.355 ppm on d 21, whereas treated animals had an average of 1.547 + 0.559 ppm. Significance was calculated at P = 0.09. Vitamin A, Fe and Se concentrations did not reach significance. Kidney and liver panel checks for animals in each group were not concerning. Future studies should look at modifying first and second sampling timepoints to be closer together. Based on results in calves with a similar study design, shortening the time between treatment and second sampling would give a clearer picture of how the neonatal supplement influenced the nutritional status of the treatment versus control animals. [ABSTRACT FROM AUTHOR]

We evaluated a saliva urea test strip (Kidney-Chek; SN Biomedical), as a rapid, noninvasive method to screen for azotemia. The test is a semiquantitative method that assesses 7 levels of saliva urea concentration, and indirectly serum urea, from <3 to >17 mmol/L. Ninety-two dogs (14 azotemic) with serum urea of 1.3–37 mmol/L and 56 cats (16 azotemic) with serum urea of 4.1–89.3 mmol/L were enrolled. A positive correlation was found for saliva urea against serum urea in each species (dogs: rs = 0.30, p < 0.005; cats: rs = 0.50, p < 0.001). After turning the semiquantitative data into continuous data by attributing to each level the midpoint of the described range, a receiver operating characteristic curve analysis showed good performance for detecting serum urea above the upper limit of the laboratory RI (dogs: 2.1–11.1 mmol/L; cats: 5–12.9 mmol/L), with an area under the curve of 0.81 in dogs and 0.83 in cats. We recommend that the test be used as an exclusion test, given that it cannot confidently confirm azotemia with higher test results. Additional investigations are recommended for dogs with a test strip reading of ≥9–11 mmol/L and for cats with a test strip reading of ≥12–14 mmol/L. [ABSTRACT FROM AUTHOR]

Depending on the year, during the winter months, cattle begin to rub bare patches on their skin due to pruritus which leads to concern from cattle producers, especially the purebred breeders. Upon further investigation by veterinarians, the cause is not always caused by lice, as many may think. This study aimed to provide insight into the cause and potential prevention/treatment of pruritic beef cattle in western Canada by examining herds that met the study's criteria of having more than 30% of the herd exhibiting pruritus. Seven herds were examined in the winter of 2023: one from Manitoba, two from Saskatchewan, and four from Alberta. Producers from each herd completed a detailed survey on treatments, nutrition, and environmental conditions and provided feed, water, and bedding samples. Within each herd, five cattle considered non-pruritic, and ten cattle considered pruritic by visual appraisal were enrolled for standard data collection consisting of documentation and photos of skin lesions localized to pruritic areas, general health clinical exam, lice exam/collection, mite exam/collection of hairs, skin hydration (corneometer), blood chemistry and vitamin/minerals, and kidney/liver enzymes for mycotoxins. A subset of the group (1 non-pruritic and 4 pruritic) was selected for advanced data collection, including dermal hypersensitivity (grass, alfalfa, grain, weeds, and molds) measured by swelling score and infrared camera temperature measurement compared with positive and negative controls, skin punch biopsies for eosinophils (IgE) and liver biopsies for copper levels. Only 21/101 cattle had lice (18 animals < 10 lice per 6.5 cm²). No significant correlation was observed between cattle with lice and being pruritic (P > 0.05). Dermal hypersensitivity was very low across both pruritic and non-pruritic cattle and was not different (P > 0.05). Skin hydration readings within animals comparing pruritic and non-pruritic areas on their body showed only one herd having significantly (P < 0.05) drier skin on pruritic locations compared with normal locations. Vitamin A, E, and copper blood analysis showed no significant difference between pruritic and non-pruritic cattle. However, liver biopsy copper levels were (P = 0.01) less in pruritic than non-pruritic cattle. Results suggest that the cause of pruritic cattle is not necessarily a result of intense lice infestations but rather multifactorial in nature, and a decision tree for producers and veterinarians should be developed to aid in determining the correct course of action to alleviate pruritic cattle in the field. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate in vivo release concentrations of lidocaine into scrotal neck tissues and tail tissues following the application of lidocaine-loaded elastrator bands (LLBs) at acute time points (0.5, 1, 2, 24, and 72 hours) and chronic time points (14, 21, 28, and 35 days). To correlate the reaction of an animal to peripheral variable nerve stimulation with scrotal tissue lidocaine concentration. To correlate cortisol and substance P concentrations in treated animals at baseline (time 0) and 24, 72, 14, 21, 28, and 35 days to a control group. Fifty lambs were divided into ten groups consisting of Acute Pain Groups: Group A: 5 intact males. After baseline body weights, blood samples, and electro-cutaneous responses were collected, animals were band-castrated and tail-docked via LLBs on day 0, time (T) = 0. At T = 0.5 hr, the band was removed, and an electro-cutaneous response was measured at the tissue at the band sites. Punch tissue biopsies (including skin and subcutaneous tissue) were collected from the areas in direct contact with the band at each site for a total of 4 biopsies per animal. Group B: repeat of group A with the band removed and animal tested at T = 1 hr, Group C: T = 2 hr, Group D: T = 24 hr, Group E: T = 72 hr, Chronic Pain Groups: Group F: T = 14 d, Group G: T = 21 d, Group H: T = 28 d, Group I: T = 35 d, Control Group: Group J: repeat of group A except animals were band castrated and tail-docking with control bands (i.e., no lidocaine) on day 0. Body weight was recorded at T = 0 and 14, 21, and 28 d. A blood sample was collected at T = 0, 24, 72 hr, then T = 8, 21, 28, and 35 d. LLBs yielded decreased stimulation scores by 1 hr (60 min) post-banding with the tails and by 2 hr (120 min) for the scrotums. There were no adverse events or device failures (i.e., band breakage or failure to castrate/taildock) observed during this study. Lidocaine-infused bands hold promise for reducing pain associated with castration and tail docking in lambs. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate an easy to administer and economical oral nutritional supplement for neonatal calves. Neonates are at risk of nutrient deficiencies because of maternal deficiencies, low body stores at birth and low nutritional intake. The pre-ruminating calf relies solely on milk for adequate immunity and nutrition until they begin ingesting forage. Insufficiencies can lead to increased morbidity and mortality. However, deficiencies in the cow are common due to variation in management, feeding and health protocols. A total of 21 beef calves in year 1 and 40 in year 2 were enrolled in the study. The calves were divided into experimental and control groups which received a vitamin-mineral supplement (VitaFerst-Care) and a saline solution at 1-3 days of age, respectively. Blood samples were collected, before, and again after supplementation (d 14 in yr 1 and d 3 in yrr 2) by jugular venipuncture. Iron and selenium concentrations were determined in blood serum of a subset of calves (n = 21 in yr1, n = 40 in yr2) by ICP-MS. All beef calves remained on their mothers. In yr 1, control calves had stable iron concentrations at 1.35 + 0.62 ppm (d 0) and 1.33 + 0.77ppm (d 14), with 50% of calves deficient. Iron concentrations in treatment calves increased slightly from 1.17 + 0.56 ppm to 1.43 +0.65 ppm. In yr 2, iron concentrations of control calves changed slightly from 1.69 + 0.91 ppm (d 0) to 1.98 +2.24 ppm (d 3). The iron concentrations in treatment calves further increased from 1.86 + 0.67 ppm to 2.33 + 2.16 ppm. Selenium concentrations were deficient in all calves in yr 1 (0.06 + 0.01 ppm) and year 2 (0.07 + 0.02 ppm) with no significant changes between treatment groups. This research provides insight regarding the severity and prevalence of nutrient deficiencies in newborn calves. All calves in the study were deficient in selenium, and between 30 to 50% were deficient in iron each year. Following supplementation, there was no significant increase in blood mineral concentrations between d 0 and d 14; however, between d 0 and d 3 there was a significant increase in blood iron concentration of calves. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of the extended-term delivery of anesthesia on the physiological and behavioral signs of pain caused by band castration in 1-month-old bull calves. Forty-eight calves (37.04 ± 8.98 days of age) were homogenously assigned by age to one of three band castration protocols (n = 16/protocol); 1) regular elastrator bands (REG), 2) regular elastrator bands preceded by two 2-mL injections of lidocaine (REG+L; LIDO-2 with epinephrine, Rafter 8 Products Inc, Calgary, Canada), and 3) lidocaine elastrator bands (LBAND; Care-Ring, Chinook Contract Research Inc., Calgary, Canada). During the castration procedure, two observers scored (from 1 to 10) how much pain each animal was experiencing (visual analog score, VAS), number of body shakes and leg kicks for each calf. Calves were weighed on d -1, 0, 14, 28, 42, and 56. Hair cortisol concentration was measured on d -1, 28, and 56. Saliva cortisol concentration was measured right after castration, 60, 120, 240 minutes after castration, on d 1 and weekly thereafter until d 56. Flight speed (FS) was recorded on d -1, right after castration, 60, 120, 240 minutes after castration, d 1, and weekly thereafter until d 56. Calf behaviors in the pen indicative of pain and discomfort were recorded on d 0, 1, and weekly thereafter until d 56. The REG+L calves tended to have decreased (P = 0.09) VAS scores than REG calves. The average daily gain was greater (P < 0.01) from d 42 to 56 than from d 1 to 42, and from d 1 to 28 compared with d 28 to 42 in all treatment groups. The REG calves had decreased (P < 0.01) hair cortisol concentrations than both REG+L and LBAND calves. Saliva cortisol concentrations were greater (P < 0.01) 60 minutes after castration than any other sample time in all treatment groups. There was an interaction between treatment and time (P = 0.04), where only LBAND had a greater FS immediately after castration compared with d -1. When calves were observed in the pen there were no treatment effects (P > 0.10) but only time differences (P < 0.05) in the frequency of head turns, oral behaviors, tail flicks, and number of standing and walking bouts. The behavioral and physiological parameters assessed showed expected results on the effects of band castrating calves, while the administration of lidocaine via REG+L or LBAND did not show any pain mitigation effect compared with the standard industry banding method (REG). [ABSTRACT FROM AUTHOR]

Infection is the leading complication associated with intravascular devices, and these infections develop when a catheter becomes colonized by microorganisms. To combat this issue, medical device manufacturers seek to provide healthcare facilities with antimicrobial medical devices to prevent or reduce the colonization. In order to adequately evaluate these devices, an in vivo model is required to accurately assess the performance of the antimicrobial devices in a clinical setting. The model presented herein was designed to provide a simulation of the subcutaneous tunnel environment to evaluate the ability of an antimicrobial peripherally inserted central catheter (PICC), coated with chlorhexidine based technology, to reduce microbial migration and colonization compared to an uncoated PICC. Three samples of control, uncoated PICCs and three samples of coated PICCs were surgically tunneled into the backs of female New Zealand White rabbits. The insertion sites were then challenged with Staphylococcus aureus at the time of implantation. Animals were evaluated out to thirty days and sacrificed. Complete en bloc dissection and evaluation of the catheter and surrounding tissue demonstrated that the chlorhexidine coated catheter was able to significantly reduce microbial colonization and prevent microbial migration as compared to the standard, un-treated catheter., 1. Introduction Indwelling intravascular devices, which are becoming integral components of modern medical practice, are associated with the high incidence of nosocomial bloodstream infections especially in intensive care patients, those [...]

The dairy industry needs evidence-based solutions to mitigate painful procedures and conditions in dairy cattle. The objective of this study was to compare the pharmacokinetic properties of orally versus subcutaneously administered meloxicam in early-lactation dairy cattle. The study was conducted at a commercial dairy herd in southwesternOntario, Canada. Twelve postpartumcowswere enrolled in the study, receiving either subcutaneousmeloxicam(MET) at 0.5mg/kg body weight (n = 6) or oral meloxicam (MOS) at a higher dose of 1.0 mg/kg body weight (n = 6) immediately following parturition. The predicted half-life (12.5 ± 2.0 vs. 28.5 ± 2.0 h), Cmax (1.59 ± 0.15 vs. 1.95 ± 0.16 μg/mL), Tmax (5.33 vs. 11.7 h), and AUC0!1 (39.6 ± 7.4 vs. 115.6 ± 19 h * μg/mL) differed significantly between MET and MOS cows, respectively. After controlling for the treatment group, first lactation cows had a significantly higher half-life (4.1 ± 2.1 h), Cmax (0.56 ± 0.2 μg/mL), and AUC0!1 (21.6 ± h * μg/mL) relative to second lactation or greater cows, respectively. Administration of meloxicam through the subcutaneous or oral route results in appreciable, dose-dependent systemic levels. [ABSTRACT FROM AUTHOR]

Parturition is a painful event experienced by cows at the onset of lactation. This pain could lead to a reduced feed intake, altered metabolic and immunological status, and a host of other diseases that could seriously limit her productive herd lifespan. The objective of the current study was to assess the effect of administration of a single dose of oral meloxicam, a non-steroidal anti-inflammatory drug (NSAID), on the production and health status of cows during their lactation. A total of 2,653 (1,009 meloxicam-treated and 1,644 untreated control) cows were enrolled across 20 herds in the provinces of Ontario and Quebec, Canada. Relative to untreated controls, meloxicam-treated cows produced 0.64 kg/day (SE = 0.29. P = 0.03) more milk over the first 3 test days (90–120 days in lactation), had 0.75 times the odds of subclinical mastitis at first test (SE = 0.08, P = 0.01), and were culled or died at 0.46 times the rate (SE = 0.16, P = 0.03) before 60 days in milk. These results are consistent with previous research and lend support to the hypothesis that parturition is a painful event in cattle. Attempts to ameliorate such pain with analgesics is associated with a variety of positive health and production outcomes. [ABSTRACT FROM AUTHOR]

The GacS/GacA two-component regulatory system in pseudomonads regulates genes involved in virulence, secondary metabolism and biofilm formation. Despite these regulatory functions, some Pseudomonas species are prone to spontaneous inactivating mutations in gacA and gacS. A gacS− strain of Pseudomonas aeruginosa PA14 was constructed to study the physiological role of this sensor histidine kinase. This loss-of-function mutation was associated with hypermotility, reduced production of acylhomoserine lactones, impaired biofilm maturation, and decreased antimicrobial resistance. Biofilms of the gacS− mutant gave rise to phenotypically stable small colony variants (SCVs) with increasing frequency when exposed to silver cations, hydrogen peroxide, human serum, or certain antibiotics (tobramicin, amikacin, azetronam, ceftrioxone, oxacilin, piperacillin or rifampicin). When cultured, the SCV produced thicker biofilms with greater cell density and greater antimicrobial resistance than did the wild-type or parental gacS− strains. Similar to other colony morphology variants described in the literature, this SCV was less motile than the wild-type strain and autoaggregated in broth culture. Complementation with gacS in trans restored the ability of the SCV to revert to a normal colony morphotype. These findings indicate that mutation of gacS is associated with the occurrence of stress-resistant SCV cells in P. aeruginosa biofilms and suggests that in some instances GacS may be necessary for reversion of these variants to a wild-type state. [ABSTRACT FROM AUTHOR]

There is a plethora of new silver-containing dressings on the market today. Various manufacturers attempt to show that their dressings are the most efficacious and therefore should be preferentially employed by health care workers based on the results of their in vitro tests. However, there have been no studies that clearly identify which tests are appropriate for comparison purposes. The purpose of this study was to determine which in vitro test is most appropriate for evaluating the antimicrobial efficacy of silver-containing dressings. This was done by testing seven silver-containing dressings and two non-silver-containing topical agents against 17 clinically relevant microorganisms using zone of inhibition assays and time-kill kinetic assays in complex media. The results for the two assays were then correlated to determine whether the methods generated similar results. It was determined that the two methods do not correlate at all. This is most likely a result of the silver interacting with the media in the zone of inhibition test, thus invalidating the results of this test. We therefore conclude that zone of inhibition data generated for silver-containing dressings is of little value when assessing antimicrobial efficacy and that time-kill assays are of greater use. [ABSTRACT FROM AUTHOR]

This study examined dermal wound healing in juvenile red Duroc pigs and determined that these animals exhibit a unique healing phenotype at multiple levels. Gross and histologic analysis revealed that full-thickness and deep dermal (1.8 mm deep) wounds both heal via formation of hypercontracted, hyperpigmented scars. Molecular analysis using reverse-transcriptase polymerase chain reaction and porcine-specific primer sets revealed that types I and III collagen, heat shock protein 47, bone morphogenetic protein-1, several proteoglycans, and tissue inhibitor of metalloproteinases 1–3 all showed a unique biphasic pattern of mRNA expression compared to previous results with Yorkshire pigs. This pattern was characterized by an initial peak of expression early after wounding, followed by a return to near-normal levels by days 28–42, and then a second increase in mRNA levels at days 56–70. The second phase of increased gene expression correlated with an increased collagen deposition as observed by picrosirius red staining and polarizing light microscopy. Reverse-transcriptase polymerase chain reaction analysis also revealed a prolonged expression of matrix metalloproteinase-2 compared to previous findings in the Yorkshire strain. Further characterization of the genetics and molecular biology associated with the red Duroc phenotype may provide insight into aberrant human wound healing. [ABSTRACT FROM AUTHOR]

Previous studies in a pig model of skin wound healing showed a coordinate expression of transforming growth factor-β (TGF-β) and connective tissue growth factor (CTGF), and exposure of porcine skin fibroblasts in vitro to recombinant human CTGF significantly up-regulated mRNA levels for a number of molecules. Therefore, based on recent reports that small interfering RNA (siRNA; double-stranded RNA) can effect silencing of the expression of gene(s), this approach has now been used with CTGF-specific siRNA to better understand the function of this growth factor in regulating matrix homeostasis and repair. Normal skin fibroblasts from Yorkshire pigs were treated with 0.1–0.8 µM CTGF siRNA, TGF-β, or TGF-β plus CTGF siRNA for 12–48 hours. Total RNA was isolated and quantified, and then mRNA levels for specific molecules were analyzed by reverse transcription-polymerase chain reaction. Protein levels for CTGF and HSP47 were assessed by Western-blot analysis. CTGF siRNA transfection led to significant decreases in mRNA and protein levels for CTGF in both a dose- and time-dependent manner. mRNA levels for types I and III procollagen, decorin, HSP47, tissue inhibitor of metalloproteinase -1, -2, -3, and basic fibroblast growth factor were also significantly and uniquely decreased following exposure of cells to CTGF siRNA. Addition of TGF-β to the cells led to increases in CTGF mRNA levels that were blocked by CTGF siRNA. CTGF siRNA exposure also significantly and selectively down-regulated TGF-β–mediated increases in mRNA levels for types I and III procollagen. The results indicate that CTGF can regulate extracellular matrix molecule, growth factor, and proteinase inhibitor gene expression, and that some of the TGF-β effects on skin fibroblasts are via a CTGF-dependent pathway. (WOUND REP REG 2004;12:–) [ABSTRACT FROM AUTHOR]

Connective tissue growth factor (CTGF) is a 38 Kda cysteine-rich, heparin-binding peptide that has been implicated in several normal and abnormal physiological processes. CTGF has been shown to be induced by transforming growth factor-β. Previous studies in our pig model of skin wound healing showed a coordinate expression of transforming growth factor-β and CTGF during the healing process. To better understand the function of CTGF during wound healing, normal porcine fibroblasts were isolated from skin samples from SPF Yorkshire pigs. At fourth passage the cells were cultured in Dulbecco's modified Eagle's medium supplemented with fetal calf serum and at 80% confluence the medium was replaced with supplemented serum-free medium. After a further 24 hours, cells were treated with 0, 10, 25, 50, 100, and 500 ng/ml of 38 Kda or 16–20 Kda (C-terminal truncated form) recombinant expressed human CTGF for 24 hours or treated with 100 ng/ml for 0, 12, 24, and 48 hours. Subsequently, CTGF effects on cell DNA synthesis and mRNA levels for a subset of relevant molecules were assessed. The results showed that in cells treated with 38 Kda rhCTGF, mRNA levels for types I and III collagen, fibromodulin, and basic fibroblast growth factor were significantly up-regulated, but mRNA levels for HSP47, decorin, biglycan, and versican were not significantly altered. mRNA levels for CTGF were also significantly increased, indicating autoregulation of expression. However, mRNA levels for transforming growth factor-β, inteleukins 1 and 6, tumor necrosis factor-α, and nerve growth factor did not change. Interestingly, mRNA levels for the tissue inhibitors of metalloproteinase-1, -2, -3 and -4 were observed to significantly increase, but in contrast, mRNA levels for matrix metalloproteinases-1, -2, -9 were not significantly altered by exposure of the cells to the 38 Kda form of CTGF. In addition, DNA synthesis was augmented in the presence of 38 Kda rhCTGF. However, the truncated 16–20 Kda form of rhCTGF appeared to have none of these effects on porcine fibroblasts. These results indicate that in order to induce changes in porcine fibroblasts a molecule with an intact C-terminal domain is required, and that CTGF regulates porcine fibroblast extracellular matrix molecule, growth factor, and proteinase inhibitor gene expression without apparently affecting matrix metalloproteinase mRNA levels. These findings suggest that CTGF contributes to the anabolic environment during skin wound healing via selective modulation of fibroblast proliferation and changes to gene expression. (WOUND REP REG 2003;11:220–229). [ABSTRACT FROM AUTHOR]

Heat shock protein (HSP) 47 is a major stress-inducible protein that is localized to the endoplasmic reticulum of avian and mammalian cells and is thought to act as a molecular chaperone specific for the processing of procollagen. However, limited information is available regarding the regulation of HSP47 during wound healing. Using a polymerase chain reaction strategy, screening of a cDNA library, and RACE-polymerase chain reaction approaches, the sequence of a full-length porcine HSP47 cDNA has been identified. The cDNA contained 2096 bp that encodes for an 18 amino acid signal peptide and a mature protein coding region consisting of 401 amino acid residues. It also included 108 bp of the 5′ noncoding region and a 731-bp 3′ noncoding region. The deduced amino acid is 83% identical to chicken, 87% identical to mouse, 88% identical to rat, and 91% identical to human HSP47. It also shares between 26% and 30% identity with different members of the serine protease inhibitor superfamily. The protein contains a RDEL endoplasmic reticulum retention signal, and two potential glycosylation sites. All of these features are characteristic of HSP47 in higher vertebrates. Heat shock treatment of porcine fibroblasts led to up-regulation of HSP47 at both the transcriptional and translational levels. HSP47 protein levels were also up-regulated during skin wound healing in a pig model. Moreover, a higher molecular weight complex at approximately 140 Kda containing HSP47 was detected at the stage of healing that was coincident with the maximal transcriptional expression of HSP47 during wound healing in this animal model. Further investigation of how HSP47 is regulated during normal and abnormal skin wound healing may lead to new therapeutic approaches to improve the healing process. (WOUND REP REG 2002;10:230–240). [ABSTRACT FROM AUTHOR]