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Simple Summary: In Texas beef markets, the expansion of ethanol production has increased the demand for and utilization of biofuel co-products, like dried distiller grains with solubles, introducing highly variable concentrations of nutrients, such as sulfur, known to impact cattle health. The risk of sulfur toxicity for Texas cattle was estimated using two mathematical nutrition models at two production stages across twelve geographic districts. The assessment identified cattle raised in the South Plains region of northwest Texas as the most susceptible to sulfur toxicity, with those in the finishing production stage being more sensitive. Results also highlighted feed ingredients and water wells by district that significantly contributed to the risk of sulfur toxicity. This research further helps better manage the risk of sulfur toxicity by providing tools translatable nationwide that properly balance beef diets and calculate anticipated sulfur exposure. The purpose of this probabilistic assessment was to estimate the risk of sulfur-induced polioencephalomalacia (S-PEM) for beef raised across Texas, from a dietary perspective. Ruminant nutritionists in Amarillo, TX, formulated two typical nutritional regimens based on cattle production stages, each containing six feed ingredients and well water. The Office of the Texas State Chemist (OTSC), National Research Council (NRC), and the published literature provided S data for feed ingredients. The Texas Water Development Board provided data for S content in Texas well water, categorized into twelve districts established by the Texas A&M AgriLife Research Extension Service. The S-PEM risk was estimated at five different eNDF levels ranging from 0% to 8% in 2% increments, using rumen degradable S (RDS) as an input value. Findings identified cattle raised in the South Plains district as the most susceptible population to S toxicity, with beef in the finishing production stage experiencing increased sensitivity. The most potential (MP) risk scenario suggested that the S-PEM risk could reach 28.5% for growers and 100% for finishers. Results further revealed that when S concentrations in well water exceeded 14.5 mg/L, water became the greatest contributor to RDS content for Texas beef, suggesting that high S content in well water is the most prominent concern for Texas beef. [ABSTRACT FROM AUTHOR]

In Veterinary Clinic, Division of Animal Health, CIRG, Makhdoom, Mathura, eighteen weaned goat kids Barbari breed (from a herd of 45 kids maintained together) were presented with the history of neurological signs. The clinical examination revealed signs including staggering gait, incoordination, muscle tremors, grinding of teeth, nystagmus and apparent blindness opisthotonus followed by collapse and recumbency. The animals were found anorectic. These goats were diagnosed as affected with Polioencephalomalacia. The affected 18 kids were treated initially with injection thiamine hydrochloride (@ 10 mg/kg 10mg/kg intravenous) diluted in 5% dextrose-normal saline (@10ml/kg intravenous) and injection dexamethasone sodium phosphate (@ 1 mg/kg intravenous). Subsequently, five doses of thiamine hydrochloride (@ 10 mg/kg body weight) were given intramuscularly every 12 hours. Out of eighteen affected weaned kids, fifteen kids responded within six hours of initial treatment and recovered completely in 3-4 days of treatment. Thus fifteen cases with neurological signs were recovered with the above protocol of treatment. Three goat kids did not respond well to the treatment and they had to be culled. [ABSTRACT FROM AUTHOR]

Cerebral cortical laminar necrosis (CLN) is a consequence of severe hypoxic, ischemic, or hypoglycemic events. In humans, these cortical lesions show characteristic linear T1‐weighted (T1W) hyperintensity in the late subacute stage. Limited information reporting magnetic resonance imaging (MRI) findings in dogs affected by CLN is available. A 3‐year‐old Belgian Shepherd dog was referred 8 days after sudden onset of blindness after general anesthesia. Neurological examination showed central blindness and mild ataxia. Three‐Tesla MRI examination of the brain revealed bilateral asymmetrical areas of T2‐weighted hyperintensity within the occipital, parietal, temporal, and frontal cortex, involving gray and white matter. Furthermore, linear T1W‐hyperintense lesions were found in the cerebral cortex of the same areas and showed heterogeneous contrast enhancement. Perfusion‐weighted images revealed hyperperfusion in the affected regions. Lesions were compatible with subacute CLN with corresponding edema suspected to be secondary to anesthesia‐related brain hypoxia. Three‐Tesla MRI enabled identification of the laminar pattern of the cortical lesions. [ABSTRACT FROM AUTHOR]

Background: Lead poisoning is one of the major toxic diseases of cattle. Contamination occurs with ingestion of products containing lead, especially batteries, or through contaminated pastures and water sources. Clinical signs are neurological and necropsy findings and histopathological changes may vary depending on the clinical presentation. Although the disease is widely reported in the literature, there are rare descriptions of intoxication in cattle raised in military training areas. This work describes the epidemiological, clinical and anatomopathological features of an outbreak of lead poisoning in cattle kept in a military artillery training camp. Case: Fifteen cattle out of a herd of sixty 4-6 year-old, mixed breed castrated males were affected. The cattle were held in a 100 ha of native pasture used for military artillery training. After three weeks in this area, the affected cattle had predominantly neurological clinical manifestations, characterized by somnolence, ambulatory incoordination, muscle tremors, bruxism, aimless walking, blindness and decubitus. The clinical course was 24-72 h. Eight of the 15 affected cattle died and two were necropsied. Necropsy finds were non-specific and the histological lesions of both necropsied cattle were restricted to the brain and kidneys. Laminar neuronal necrosis, neuropil vacuolization (spongiosis) and vascular endothelial hypertrophy were observed in the telencephalic cortex. Additionally there was astrocytic degeneration and neuronophagia. There was degeneration and necrosis of renal tubular epithelium and in one bovine there were intranuclear inclusion bodies in the renal epithelial cells; these inclusion bodies were highlighted using both modified Ziehl-Neelsen and periodic acid Schiff (PAS) stains. The levels of lead found in the kidneys and livers of the two necropsied cattle were respectively 51.7 μg/g and 41.00 μg/g for one of the necropsied cattle; and 431μg/g and 39.0 μg/g for the other. After the diagnosis of intoxication, cattle were removed from the area and the remaining seven affected bovines recovered. Discussion: The diagnosis of lead poisoning in cattle in the current study was based on epidemiological, clinical, anatomopathological data and in the determination of lead levels in the kidney and liver. The association of these data provides an invaluable aid in confirming a presumptive diagnosis of lead poisoning. Pasturing on military artillery training fields is a rarely described form source of lead for the intoxication in bovine species. In such cases, cattle may ingest the lead directly from the soil or through contaminated pastures containing lead dust on the surface of the leaves. Histologically, laminar neuronal necrosis in the telencephalic cortex, associated with tubular necrosis and intranuclear inclusion bodies in tubular epithelial cells, are characteristic features of the intoxication. These changes are usually associated with ischemic anoxia in the nervous system and alteration in nuclear function which interferes in gene expression in the kidney. Lead poisoning in cattle should be differentiated from other neurological conditions, especially rabies, hepatic encephalopathy and several causes of polioencephalomalacia. Areas of military artillery training are unfit for the development of agricultural exploitation activities, as they represent potential sources of contamination for livestock. [ABSTRACT FROM AUTHOR]

Twenty-four steers (initial BW = 385 ± 1.1 kg) were blocked by BW and randomly assigned to 3 dietaty treatments (0, 30, or 60% wet distillers grains with solubles [WDGS]; DM basis) and were fed individually to determine the effect of WDGS on live growth and carcass performance, visceral organ mass, trace mineral status, and polioencephalomalacia biomarkers. Steers were slaughtered at 125, 150, 164, and 192 d (2 blocks/ slaughter date) when external fat depth was approximately 1.3 cm based on visual appraisal. Steers fed 30% WDGS had greater DMI than those fed 0 or 60% WDGS (P < 0.05), and steers fed 60% WDGS had the lowest carcass-adjusted ADG (P < 0.09) of the 3 treatments. Nonetheless, WDGS concentration did not alter feed efficiency (P > 0.41) on either live or carcass-adjusted basis. Steers fed 30% WDGS had greater liver S and Mn concentrations (DM basis) and lower liver Fe concentrations than control steers (P <0.10; initial values used as a covariate), and feeding 60% WDGS decreased liver Cu and increased liver Fe (P <0.10) compared with feeding 30% WDGS. Cytochrome c oxidase (COX) activity in brain tissue tended to be decreased with 60 vs. 30% WDGS (P = 0.12), and COX activity decreased linearly (P = 0.06) in lung tissue as dietaty WDGS concentration increased. Likewise, gut fill linearly increased (P = 0.01 ) with increasing WDGS concentration. Feeding 30% WDGS increased fractional mass (g/kg of empty BW) of the small intestine (P < 0.10) compared with controls, whereas 60% WDGS increased fractional kidney mass (P <0.10) compared with 30% WDGS. Overall, results suggest that gut fill, Cu status, and COX activity seem to be compromised by WDGS when fed at 60% of diet DM in diets based on steam-flaked com, which suggests a greater susceptibility to polioencephalomalacia. [ABSTRACT FROM AUTHOR]

Polioencephalomalacia as a result of sulphur excess is a growing problem in cattle and sheep, mainly in young, growing animals. It is common in different regions of the world. The disease develops favoured by certain conditions such as sustained provision of feed and water with high sulphur content, use of dietary supplements containing sulphur, and a habitat with high hydrogen sulphide concentration. Pathogenesis of the disease is complex, but very important are oxidative-antioxidative imbalance, dysfunction of vessels, and secondary cerebral cortex ischaemia as a result of direct and/or indirect action of sulphur metabolites, namely hydrogen sulphide, sulphides, and sulphites. Clinical signs and changes in the cerebral cortex in the form of degenerative necrotic lesions are similar to those observed in polioencephalomalacia caused by vitamin B1 deficiency, and lead and salt intoxication. Highly increased sulphur content (more than 0.3-0.4 of dry matter) in the diet is the basis for differential diagnosis, as well the high concentration of hydrogen sulphide in gas and sulphides in rumen fluid. In prophylaxis and treatment the most important measure is to limit sulphur intake and in acute cases to neutralise low pH in rumen and administer vitamin B1 injections. [ABSTRACT FROM AUTHOR]

This study examined the role of sulfur (S) in the pathogenesis of S-induced polioencephalomalacia (PEM) in beef cattle in the context of thiamine status and metabolism. Thiamine, thiamine monophosphate (TMP) and thiamine pyrophosphate (TPP) status in rumen fluid, blood and brain tissue were determined in beef heifers fed 2 levels of S [low S (LS) vs. high S (HS)] at 2 forage-to-concentrate ratios (F:C). High S diet did not affect ruminal and blood thiamine status. Interestingly, however, HS diet showed increased brain thiamine levels. No gross or histopathological changes indicative of PEM were detected in the brains of the heifers. Of note, during the course of the present study, we documented an outbreak of S-induced PEM in commercial feedlot steers. Brain thiamine variables in experimental animals fed HS diet were then contrasted with brain thiamine status in PEM affected feedlot steers. Interestingly, in clinically normal animals, exposure to HS diet resulted in increased levels of both TMP and TPP in the brain tissue, in comparison to animals fed LS diet. In contrast, the PEM affected brains showed overall lower levels of thiamine phosphates. It is noteworthy that TPP levels were 36.5% lower, despite 4.9-fold higher free thiamine in PEM brains compared to normal brains. Our results indicate that high dietary S may increase the metabolic demand for TPP, and that animals incapable of maintaining requisite levels of brain TPP are at high risk to develop fulminant cerebrocortical necrosis. [ABSTRACT FROM AUTHOR]

Sulphur-induced polioencephalomalacia (sPEM), a neurological disorder affecting ruminants, is frequently associated with the consumption of high-sulphur (S) water and subsequent poor performance. Currently, there is no economical method for S removal from surface water sources, and alternative water sources are typically neither readily available nor cost-effective. Determination of genes differentially expressed in response to high-S water consumption may provide a better understanding of the physiology corresponding to high dietary S and ultimately lead to the development of treatment and prevention strategies. The objective of this study was to determine changes in gene expression in the liver, an organ important for S metabolism, of fibre-fed steers consuming high-S water. For this study, liver tissues were collected on the final day of a trial from yearling steers randomly assigned to low-S water control (566 mg/kg SO4; n = 24), high-S water (3651 mg/kg SO4; n = 24) or high-S water plus clinoptilolite supplemented at either 2.5% ( n = 24) or 5.0% ( n = 24) of diet dry matter (DM). Microarray analyses on randomly selected healthy low-S control ( n = 4) and high-S ( n = 4; no clinoptilolite) steers using the Affymetrix GeneChip Bovine Genome Array revealed 488 genes upregulated (p < 0.05) and 154 genes downregulated (p < 0.05) in response to the high- vs. low-S water consumption. Real-time RT-PCR confirmed the upregulation (p < 0.10) of seven genes involved in inflammatory response and immune functions. Changes in such genes suggest that ruminant animals administered high-S water may be undergoing an inflammation or immune response, even if signs of sPEM or compromised health are not readily observed. Further study of these, and other affected genes, may deliver new insights into the physiology underlying the response to high dietary S, ultimately leading to the development of treatments for high S-affected ruminant livestock. [ABSTRACT FROM AUTHOR]

Abstract: The incidence of polioencephalomalacia and concentrations of ruminal hydrogen sulfide ([H2S]) in feedlot cattle appear to be greatest during the first 30 days of being fed a high sulfur (S) finishing diet. It was hypothesized that delaying exposure to high-S until cattle are fully adapted to a high-concentrate diet would reduce the peak [H2S], thus reducing potential for S-induced polioencephalomalacia. Sixty Angus crossbred-steers were moved into the feedlot and fed a moderate S (0.3% S) step-up diet for 7 days. Then steers were weighed (443±12.8kg), blocked by weight, and randomly assigned to one of three dietary treatments: (1) two moderate-S (0.3% S) step-up diets fed for 7d each (days 1–14) followed by a moderate S finishing diet (days 15–98; MS), (2) two high-S (0.6% S) step-up diets fed for 7d each (days 1–14) followed by a high S finishing diet (days 15–98; HS), or (3) two moderate-S (0.3% S) step-up diets fed for 7d each (days 1–14) followed by a moderate S finishing (0.3% S) diet for the first 28 days of the finishing period (days 15–42), followed by the high-S diet (0.6% S) for the remainder of the trial (days 43–98; Delayed S; DS). Ruminal [H2S] and pH were measured 6h post-feeding on days 15, 21, 28, 42, 49, 56, 70, 84, and 98. The numerically greatest [H2S] (4948mg/L) occurred in HS-steers on day 42 (28d on the finishing ration) and on day 70 (28d after starting high-S) for DS-steers (3690mg/L). The maximum [H2S] of HS-steers tended to be greater (P=0.09) than DS-steers, despite S intake not differing (P=0.75). The elevated ruminal [H2S] of HS-steers on day 42, was likely not due to a decreased ruminal pH during adaptation to the finishing diet as pH did not differ due to treatment (P=0.40) or day (P=0.16). Overall, HS-steers had a 15% decrease (P=0.02) in average daily gain compared to MS-steers whereas gain of DS-steers was intermediate, not differing from MS (P=0.13) or HS (P=0.26) steers. These findings suggest that there may not be any additional increase in steer gains by delaying S inclusion in the diet until after the first 28 days of finishing, though it may decrease the maximum ruminal H2S concentration. [Copyright &y& Elsevier]

Poor performance and S-induced polioencephalomalacia (sPEM) have been observed in ruminant livestock in high-S drinking water regions. No gainful method of removing S from drinking water is available and therefore a feed supplement that negates the effects of high-S water is needed. Our objective was to determine if supplementing Mo improves health and performance of steers administered a high-fiber diet and high-S drinking water. We hypothesized that if the supplemental Mo adequately bound excess S in the rumen, it would not be available at toxic concentrations. Yearling steers (n = 96; 260.0 ± 1.3 kg BW) were stratified by pretrial BW into 12 feedlot pens (n = 8 steers per pen). One of 3 treatments, low-S water (LS; 375 mg S04/L), high-S water (HS; 2,218 mg S04/L), or high-S water plus Mo (HSMO; 2,218 mg S04/L; 187.5 mg Mo/kg DM), were randomly assigned to pens within 4 blocks for a 56-d trial. Body weights were recorded on d -2, -1, 29, 56, and 57, ruminal H2S concentrations were measured by rumenocentesis on d -1, 29, and 57, and liver biopsies were performed on d -1 and 57. Performance data were analyzed over the 56-d trial period (overall) as well as over 2 periods: Period 1 (d 0 to d 28) and Period 2 (d 29 to d 56). One case of sPEM was confirmed by the presence of cortical lesions in the HS treatment group. Daily DMI and ADG were affected by treatment and period (P < 0.001) main effects. The LS steers had the greatest (P < 0.05) DMI followed by HS and HSMO steers, respectively. Similar results were observed for ADG. Daily water intake was affected (P < 0.001) by period only, with greater daily water intake in Period 2 than Period 1. Change in hepatic concentrations of Cu, Fe, and Mo over the course of the trial were all affected (P < 0.001) by treatment. Hepatic Cu increased from d 1 to 57 in LS and HS steers but was depleted in HSMO steers. Hepatic Fe and Mo increased in HSMO steers only. Ruminal H2S concentrations were affected by treatment (P < 0.021), with greater H2S concentrations in HSMO compared with LS and HS steers. Signs of Mo toxicity such as severe diarrhea, loss of body condition, anorexia, changes in hair color, and stiffness in joints were observed in the Mo supplemented steers. These results indicate that added dietary Mo does not adequately bind excess S in the rumen, causing aggravated toxic effects from potentially both the high dietary S and Mo. [ABSTRACT FROM AUTHOR]

Feeding increased concentrations of distillers dried grains with solubles (DDGS) to ruminants has been avoided due to risks of S toxicity and concerns about animal performance. The objective of this study was to evaluate the influence of feeding an increasing concentration of DDGS and corn processing method on animal performance, incidence of polioencephalomalacia (PEM), and concentration of H2S gas in feedlot steers. Sixty steer calves (336 ± 13.2 kg) were individually fed for an average of 136 d in a completely random design with a 3 x 2 factorial arrangement of treatments. Main effects included concentration of DDGS (20, 40, or 60% DM basis) and corn processing method [highmoisture (HMC; 71.7% DM) vs. dry-rolled corn (DRC; 86.2% DM)] resulting in treatments of 1) 20% DDGS with DRC, 2) 40% DDGS with DRC, 3) 60% DDGS with DRC, 4) 20% DDGS with HMC, 5) 40% DDGS with HMC, and 6) 60% DDGS with HMC. Ruminal H2S gas concentrations were measured on d 0, 7, 14, 21, 28, 35, 49, 63, and 91 via rumen puncture. Animal performance and carcass characteristic data were collected. The day x corn processing x DDGS interaction for H2S gas concentrations was not significant (P = 0.91). Ruminal H2S concentration increased with increasing DDGS concentration (P < 0.001) and day (P < 0.001), but was not influenced by corn processing method (P = 0.94). Carcass-adjusted final BW decreased linearly (P = 0.009), whereas carcass-adjusted ADG decreased quadratically (P = 0.05) with increasing concentration of DDGS in the diet. Carcass-adjusted G:F was not affected (P ≥ 0.28) by increasing concentration of DDGS in the diet. Carcass characteristics reflected the decrease in final BW with decreased HCW (P = 0.009), as well as decreased fat depth (P 0.005) with increasing concentrations of DDGS. The combination of decreased HCW and backfat thickness resulted in decreased (P = 0.02) yield grade with increasing DDGS inclusion. There were no confirmed cases of PEM. In conclusion, corn processing did not influence animal performance, incidence of PEM, or H2S concentrations under the conditions of this study. Feeding 60% DDGS in beef cattle finishing diets is not recommended due to poor animal performance. [ABSTRACT FROM AUTHOR]

Limited data are available regarding the influence of thiamine supplementation on the incidence of polioencephalomalacia (PEM) in lambs fed diets containing increased concentrations of S in the diet (>0.7%). Therefore, our objective was to evaluate the influence of thiamine supplementation on feedlot performance, carcass quality, ruminal hydrogen sulfide gas concentrations, and incidence of PEM in lambs fed a finishing diet containing 60% distillers dried grains with solubles (DDGS; DM basis). Two studies were conducted using completely randomized designs to evaluate the influence of concentration of thiamine supplementation. Study 1 used 240 lambs fed in 16 pens, whereas study 2 used 55 individually fed lambs. Lamb finishing diets contained 60% DDGS, which resulted in a dietary S concentration of 0.73% (DM basis). Treatments diets were based on the amount of supplemental thiamine provided: 1) no supplemental thiamine (CON), 2) 50 mg/animal per day (LO), 3) 100 mg/animal per day (MED), or 4)150 mg/animal per day (HI). Additionally, in study 2, a fifth treatment was included, which contained 0.87% S (DM basis; increased S provided by addition of dilute sulfuric acid) and provided 150 mg of thiamine/animal per day (HI+S). In study 1, ADG decreased quadratically (P = 0.04), with lambs fed the CON, LO, and MED diets gaining BW at a greater rate than lambs fed the HI diet. In study 1, DMI responded quadratically (P < 0.01), whereas G:F tended to differ linearly (P = 0.08) to concentration of thiamine supplementation, with MED lambs having greater DMI and decreased G:F. No differences (P ⩾ 0.17) in lamb performance were observed in study 2. In both studies, most carcass characteristics were unaffected, with the exception of a tendency for decreased carcass conformation (study 1; P = 0.09) and greater flank streaking (study 2; P = 0.03). No differences in ruminal hydrogen sulfide concentration (P> 0.05) among treatments were apparent until d 10, at which point lambs fed the LO diet had less hydrogen sulfide concentrations than all other treatments. Lambs fed HI had the greatest concentrations of hydrogen sulfide on d 31 (1.07 g of hydrogen sulfide /m3 P < 0.009). Ruminal pH did not differ (P = 0.13) and averaged 5.6 ± 0.06. No clinical cases of PEM were observed during the course of either study. The use of thiamine as a dietary additive to aid in the prevention of PEM in finishing lambs does not appear to be necessary under the conditions of this study. [ABSTRACT FROM AUTHOR]

Sulfur-induced polioencephalomalacia (sPEM), a neurological disorder affecting ruminants, is associated with consumption of diets with increased S (high-S). High-S water is commonly found in many western states and is a major source of dietary S for grazing cattle. Consumption of high-S water has been associated with sPEM and decreased performance. Identification of a feed supplement that would counteract the negative effects of high-S water would decrease the incidence of sPEM and prevent performance reductions in regions with problematic water sources. The objectives of this study were to 1) determine the effects of administering high-S drinking water to foragefed feedlot steers on health and performance, and 2) determine the effectiveness of clinoptilolite, a clay mineral with increased cation-exchange capacity, in negating the effects of high-S drinking water. Yearling steers (n = 96; 318.2 ± 2.1 kg of BW) were randomly assigned to 1 of 4 treatments for a 77-d trial period: control with low-S water (566 mg of S04/L), high-S water (3,651 mg of S04/L), or high-S water plus clinoptilolite supplemented at 2.5 or 5.0% of the diet DM. Feed and water consumption were measured daily, .and all steers were weighed on d -2, -1, 29, 53, 76, and 77. Plasma sam-ples were collected on d 0, 58, and 77, and liver samples on d 0 and 77. There was a greater (P ⩾ 0.046) frequency of sPEM in high-S steers than control steers, but no differences among high-S treatment groups. In total, 12 cases of sPEM were confirmed by the presence of cortical lesions in steers consuming high-S water. Daily DM1 (P = 0.002) and daily water intake (P = 0.001) were less in high-S water steers than control steers. No differences (P> 0.546) in ADG or G:F were observed. Plasma Cu decreased (P = 0.029) to a greater magnitude in high-S water steers than the control steers over the 77-d trial period. Mineral analyses of hepatic tissue from randomly selected healthy steers from each treatment group (n = 10 per treatment) showed an interaction (P < 0.034) of sample time and treatment for Cu, Se, and Zn concentrations. These results suggest that clinoptilolite does not negate the effects of high-S water, and administration of high-S water decreases herd health through an increased incidence of sPEM and reduced nutritional status. [ABSTRACT FROM AUTHOR]

A case of a neurological disease affecting adult camels (locally called Altair) was described. A female camel was presented with typical clinical signs: weakness of legs, continuous head shaking especially when the animal was stressed and wry neck. There were no respiratory, cardiovascular or digestive abnormalities. The she-camel ate and drank normally. Complete blood count results and liver and kidney functions were normal. No visible macroscopic lesions were seen in the carcass except for meningeal congestion. Microscopic examination of the brain showed malacic lesions and the meninges were congested and oedematous. The concentration of sulphur in the drinking water was 13.56 ±5.8 g/L which is considered very high for the nutrition of farm animals. The concentration of copper, molybdenum and selenium in water and feed were normal. [ABSTRACT FROM AUTHOR]

In this study, thiamine-responsive polioencephalomalacia (PEM) has been detected in sporadic cases of 8 adult dromedary breeding camels at different farms around Tripoli. Clinical cases showed variable signs including disorientation, aimless walking with a high stepping gait due to blindness, anorexia, opisthotonus or head retraction (star gazing), muscle tremor, convulsion and recumbency. Post mortem was carried on one recumbent camel, with particular attention to examine brain tissue for evidence of the disease gross and histopathological lesions which shows positive results of PEM. The result of the study of clinical cases treated by parenteral injection of thiamine preparation showed a good response within 6 hours after initial treatment. The immediate response to the specific treatment was diagnostic for PEM and can differentiate it from other neurological conditions based on the animal's response to injection of thiamine beside specific clinical findings and necropsy lesions in the brain of sacrificed camel. [ABSTRACT FROM AUTHOR]

Polioencephalomalacia was diagnosed histologically in cattle from two herds on the Darling Downs, Queensland, during July–August 2007. In the first incident, 8 of 20 18-month-old Aberdeen Angus steers died while grazing pastures comprising 60% Sisymbrium irio (London rocket) and 40% Capsella bursapastoris (shepherd's purse). In the second incident, 2 of 150 mixed-breed adult cattle died, and another was successfully treated with thiamine, while grazing a pasture comprising almost 100% Raphanus raphanistrum (wild radish). Affected cattle were either found dead or comatose or were seen apparently blind and head-pressing in some cases. For both incidents, plant and water assays were used to calculate the total dietary sulfur content in dry matter as 0.62% and 1.01% respectively, both exceeding the recommended 0.5% for cattle eating more than 40% forage. Blood and tissue assays for lead were negative in both cases. No access to thiaminase, concentrated sodium ion or extrinsic hydrogen sulfide sources were identified in either incident. Below-median late summer and autumn rainfall followed by above-median unseasonal winter rainfall promoted weed growth at the expense of wholesome pasture species before these incidents. [ABSTRACT FROM AUTHOR]

Acute and subacute ruminal acidosis, bloat, liver abscesses, and polioencephalomalacia (PEM) were reviewed with respect to contributions published in the Journal of Animal Science (JAS) regarding these metabolic and digestive disorders in beef cattle. Increased grain feeding and expansion of the feedlot industry in the 1960s led to considerable research on acidosis, and. early publications defined ruminal changes with acute acidosis. The concept of subacute acidosis was developed in the 1970s. Significant research was published during the 1980s and 1990s on adaptation to high-grain diets, effects of ionophores, and the development of model systems to study ruminal and metabolic changes in acidosis. Since 2000, JAS publications on acidosis have largely focused on individual animal variability in response to acid loads and the role of management strategies in controlling acidosis. Increased grain feeding also was associated with an increase in the incidence of liver abscesses, which were quickly linked to insults to the ruminal epithelium associated with acidosis. The role of antibiotics, particularly tylosin, in decreasing the incidence and severity of liver abscesses was a significant contribution of JAS publications during the 1970s and 1980s. Papers on bloat were among the earliest published in JAS related to metabolic and digestive disorders in cattle. Noteworthy accomplishments in bloat research chronicled in JAS include the nature of ruminal contents in legume and feedlot bloat, the role of plant fractions and microbial populations in the development of bloat, and the efficacy of poloxalene, ionophores, and, more recently, condensed tannins in decreasing the incidence and severity of bloat. Although less research has been published on PEM in JAS, early publications highlighting the association between PEM and ruminal acidity and the role of thiaminase in certain forms of the disorder, as well as more recent publications related to the role of sulfur in the development of PEM, are noteworthy contributions. Since the 1940s, outstanding and often-cited review articles have made JAS a highly visible source of information on these disorders. Thus, JAS has played a significant role as a repository for information pertaining to metabolic and digestive disorders in cattle and other ruminants, and it will no doubt continue to be a premier resource for information on these conditions during the second century of the American Society of Animal Science. [ABSTRACT FROM AUTHOR]

Background: Thiamine status of ruminants is adversely affected in acidic rumen conditions. However, there have been limited published case study data related to thiamine deficiency of ruminants with acute ruminal lactic acidosis (ARLA). Hypothesis: Thiamine deficiency would occur in sheep with ARLA. Animals: Thirteen Ak-Karaman (white Karaman) sheep with ARLA, aged 1 year (ARLA group) and 10 healthy Ak-Karaman sheep, aged 1 year (control group) were used. Methods: After clinical examination, rumen fluid samples of all sheep were obtained with a stomach tube and examined immediately. Blood samples were taken from a jugular vein of the sheep. Erythrocytic transketolase enzyme activity and hence thiamine pyrophosphate (TPP) effect were determined according to Clausen's method. Results: History revealed that all sheep in the ARLA group had accidentally consumed excessive amounts of cracked barley. During clinical examination of the ARLA group, disturbed general condition, engorged scleral vessels, moderate to severe dehydration, and ruminal atony were recorded in the sheep. The results of the ruminal fluid analyses of the ARLA group demonstrated characteristics of ARLA. The results of clinical and ruminal fluid examination of control group were normal. The mean TPP effect (%) in the ARLA group (109 ± 28) was significantly higher than in the control group (22.2 ± 3.7) ( P < .001). Conclusions and Clinical Importance: The present study revealed that severe thiamine deficiency occurred in sheep with ARLA. This result indicates that thiamine administration to sheep suffering from acute ruminal acidosis caused by overconsumption of readily fermentable carbohydrates could be beneficial in alleviating thiamine deficiency caused by ruminal acidosis. [ABSTRACT FROM AUTHOR]

A study was made to investigate faecal thiaminase and the thiamine-related biochemical changes in apparently normal replacement ewes with a feed change, after the initiation without adaptation to the new pasture. Twenty-four female ewes were divided into two groups. Group A was managed in a system based on pasture and was compared with group B system based on a diet of concentrate and straw until moving to pasture 9 weeks after. Blood samples for lactate, pyruvate and erythrocyte transketolase activity determinations and faeces for thiaminase estimation were evaluated chronologically. At the end of a 126 days experimental period, live weights of groups were similar. We confirmed that clinically normal sheep may have thiaminase activity in the faeces and concluded that the thiaminase release increased during the diet changes, from concentrate to pasture, and that their continued excretion could develop some degree of thiamine deficiency. [ABSTRACT FROM AUTHOR]

This report describes clinical and pathological findings associated with closantel (a halogenated salicylanilide anthelmintic) overdosage in a 3-year-old goat. The clinical signs included blindness, incoordination, ataxia, depression of the palpebral and pupillary reflexes, and recumbency. No gross lesions were noted in tissue or organs at necropsy, but microscopic lesions were seen in nervous tissue and hepatic cells. Polioencephalomalacia was clearly evident. Bilaterally symmetrical status spongiosus of the white matter of the brain, bilateral laminar necrosis, microcavitations, ischaemic cell change and severe degeneration of the cerebellum were seen in nervous tissue. Fatty change and hydropic degeneration in the liver and hepato-cellular degeneration were observed histologically. [ABSTRACT FROM AUTHOR]