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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]

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]

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]

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]

The expression of bone morphogenetic protein-7 (BMP-7) mRNA by in situ hybridization in rats with normal kidneys and those with acute renal failure has been studied cloning a rat BMP-7 cDNA and using it as a probe. BMP-7 is a member of the transforming growth factor-beta superfamily that are found abundantly in the fetal kidney. Results indicated that the BMP-7 mRNA has the highest expression in tubules of the outer medulla. Its expression is also localized to the adventitia of renal arteries, the epithelial cell layer of the renal pelvis and the ureter.

A study was conducted on the mechanism by which hepatic endothelin (ET) production is enhanced during endotoxin exposure. The findings suggest a model of paracrine signaling to describe the mechanism for the elevation of hepatic ET-1 levels following endotoxin exposure. This paracrine signaling mechanism operates between Kupffer cells that release transforming growth factor-Beta on endotoxin challenge and hepatic endothelial cells.

The characterization and partial purification of secretory platelet-activating factor (PAF)-acetylhydrolase of the rat hepatobiliary system were conducted. The objective is to show that both rat hepatocytes and Kupffer cells secrete constitutive pPAF-AH (plasma-type platelet-activating factor-acetylhydrolase) in cultured mediums. Results demonstrate that rat bile contains substantial amounts of PAF-AH exhibiting pPAF-AH properties.

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 roles of endothelin A (ETA) and (ETB) B receptors on bone formation was analyzed in primary cultures of rat fetal calvarial cells to characterize osteoblast responsiveness to ET-1. Analysis of the effects of osteogenic protein (OP)-1 on ET-1 receptor expression indicated the presence of downregulated ETA gene expression in the presence of high levels of OP-1. Furthermore, ET-1 modulated osteoblastic function during discrete phases of osteoblast development.

The effects of endotoxemia on endothelin-1 synthesis by hepatic endothelial cells were analyzed in intact livers isolated from endotoxin-treated rats. Analysis of liver cells from endotoxemia-treated rats indicated the presence of elevated ET-1 hepatic messenger RNA expression. Analysis of liver cell types from endotoxin-treated rats also indicated high ET-1 concentrations in the hepatic endothelial cells. Furthermore, endotoxemia elevated the levels of circulating immunoreactive ET-1 in endotoxin-treated rats due to systemic trauma.