Abstract Crossbred beef steers [n = 400; body weight (BW) = 370 ± 8 kg] were used to evaluate the effects of trace mineral (TM) source and chromium propionate (Cr) on rumen fermentation characteristics, plasma glucose and mineral concentrations, performance, and carcass characteristics in feedlot steers fed a steam-flaked corn-based finishing diet. Steers were blocked by initial BW and randomly assigned within block to 1 of 4 treatments (10 steers/pen) with 10 pens per treatment. The experimental design was a randomized complete block design with a 2 x 2 factorial arrangement of treatments. Factors included: 1) TM source [sulfate or hydroxychloride (IntelliBond] Cu, Mn, and Zn TM supplemented at 18, 40, and 90 mg/kg DM, respectively) and 2) with or without supplemental Cr (KemTRACE) at 0.0 or 0.25 mg/kg DM. Steers were individually weighed on d -1 and 0 and every 28 d throughout the experiment. Jugular blood samples and rumen contents were collected from 10 steers per treatment on d 28 and 84 of the experiment for plasma glucose and TM concentration and volatile fatty acid analysis, respectively. On d 154 of the experiment, steers were harvested at a commercial abattoir and carcass data was collected. Data were analyzed on a pen mean basis for a randomized complete block design using PROC MIXED of SAS. There was no TM source by Cr supplementation interactions for any of the response variables measured, therefore only main effects are reported. Overall ADG (P = 0.03) and gain:feed (P = 0.02) were greater in steers receiving supplemental Cr when compared with steers not supplemented with Cr. Hot carcass weight (P = 0.04), dressing percentage (P = 0.01), longissimus muscle area (P = 0.03), and USDA yield grades (P = 0.04) were greater in steers receiving hydroxychloride TM compared with steers receiving sulfate TM. Steers supplemented with Cr had a greater dressing percentage (P = 0.01) and longissimus muscle area (P = 0.04) compared with steers not supplemented with Cr. On d 28 of the experiment, ruminal acetate concentrations were lesser (P = 0.01) and ruminal propionate concentrations tended to be greater (P = 0.12) in steers receiving hydroxychloride TM compared with steers receiving sulfate TM. Steers supplemented with Cr had greater ruminal acetate concentrations (P = 0.04) and plasma glucose concentrations (P = 0.05) on d 28 of the experiment when compared with non-supplemented controls. These data indicate the Cr supplementation and TM source can influence feedlot steer performance, carcass characteristics, and rumen fermentation characteristics.

Angus-crossbred steers (n = 400; 369.7 +/- 7.6 kg) were used to determine the influence of trace mineral (TM) source and chromium propionate (Cr Prop) supplementation on performance, carcass characteristics, and ruminal and plasma variables in finishing steers. Steers were blocked by body weight (BW) and randomly assigned within block to treatments in a 2 x 2 factorial arrangement, with factors being: 1) TM source (STM or HTM) and 2) Cr supplementation (0 or 0.25 mg Cr/kg DM, -Cr or + Cr, respectively). Treatments consisted of the addition of: 1) sulfate TM (STM; 90, 40, and 18 mg/kg DM of Zn, Mn, and Cu, respectively), 2) STM and 0.25 mg Cr/kg DM from Cr Prop, 3) hydroxychloride TM (HTM; 90, 40, and 18 mg/kg DM of Zn, Mn, and Cu, respectively), and 4) HTM and 0.25 mg Cr/kg DM from Cr Prop. Each treatment consisted of 10 replicate pens with 10 steers per pen. Body weights were obtained on consecutive days at the initiation and termination of the 154-d study. Steers were fed a steam-flaked corn-based finishing diet. Ractopamine hydrochloride was fed for the last 31 d of the study. Ruminal fluid and blood samples were obtained from one steer per pen on days 28 and 84 for ruminal volatile fatty acids (VFA) and plasma TM and glucose analysis. Steers were slaughtered at the end of the study and individual carcass data were collected. No Cr x TM source interactions (P = 0.48) were detected. Steers supplemented with HTM had greater (P = 0.04) hot carcass weight (HCW), dressing percentage (DP), longissimus muscle (LM) area, and USDA yield grade (YG), and tended (P = 0.12) to have greater average daily gain (ADG) than those receiving STM. Average daily gain, gain:feed, dressing percentage, and longissimus muscle area were greater (P = 0.04) for + Cr steers compared to-Cr steers. Hot carcass weight tended (P = 0.06) to be greater for + Cr steers. Ruminal acetate concentrations at 28 d were lesser (P = 0.01) for HTM vs. STM steers, and greater (P = 0.04) for + Cr steers compared to-Cr steers. Plasma concentrations of Zn, Cu, and Mn were not affected by TM source or Cr supplementation. Steers supplemented with Cr had greater (P = 0.05) plasma glucose concentrations than-Cr steers at 28 but not at 84 d. Results of this study indicate replacing STM with HTM improved carcass characteristics in finishing steers, and Cr Prop supplementation improved steer performance and carcass characteristics. This research indicates that chromium propionate supplementation improves performance and carcass characteristics in finishing steers. Steers supplemented with hydroxychloride forms of zinc, copper, and manganese had improved carcass characteristics compared to those receiving sulfate forms. Trace minerals (TM) are supplemented to finishing cattle diets to prevent TM deficiencies. Sources of TM differ in their bioavailability and effect on rumen fermentation. Chromium is a TM required in low concentrations to enhance insulin activity. We tested the effect of TM source (hydroxychloride; HTM vs. sulfate; STM) and supplemental Cr propionate (Cr Prop) on performance and carcass characteristics of finishing steers. Providing 0.25 mg of supplemental Cr/kg DM, from Cr Prop, improved gain, feed efficiency, and carcass characteristics in steers. Steers supplemented with HTM tended to gain faster and had improved carcass characteristics of economic importance compared to those supplemented with STM.

The objective of this study was to evaluate the effects of dietary chromium (Cr), as Cr propionate (Cr Prop), on measures of insulin sensitivity in turkeys. Plasma glucose and nonesterified fatty acid (NEFA), and liver glycogen concentrations were used as indicators of insulin sensitivity. One-day-old Nicholas Large White female poults (n = 336) were randomly assigned to dietary treatments consisting of 0 (control), 0.2, 0.4, or 0.6 mg supplemental Cr/kg diet. Each treatment consisted of 12 replicate cages with 7 turkeys per cage. Final BW were taken on d 34, and on d 35 two birds from each cage were sampled for plasma glucose and NEFA, and liver glycogen determination at the initiation (fed state) and termination (fasted state) of a 24-h fast. Following a 24-h fast, 2 turkeys per cage were refed (refed state) their treatment diet for 4 h, and then harvested. Feed/gain and ADG did not differ between control and Cr-supplemented turkeys over the 34-d study, but feed intake tended (P = 0.071) to be greater for controls than turkeys receiving 0.4 mg Cr/kg diet. Fed turkeys had greater plasma glucose (P = 0.002) and liver glycogen (P = 0.001) concentrations, and lower (P = 0.001) NEFA concentrations than fasted birds. Turkeys refed after fasting had greater (P = 0.001) plasma glucose and liver glycogen concentrations, and lower (P = 0.001) plasma NEFA levels than fed turkeys. Liver glycogen and plasma NEFA concentrations did not differ among control and Cr-supplemented birds in the fed, fasted, or refed state. Plasma glucose concentrations were not affected by treatment in fed or fasted turkeys. Turkeys supplemented with 0.2 or 0.4 mg Cr/kg and refed after fasting had lower (quadratic, P = 0.038) plasma glucose concentrations than controls. Plasma glucose concentrations in refed birds did not differ among Cr-supplemented turkeys. The lower plasma glucose concentration in Cr-supplemented turkeys following refeeding is consistent with Cr enhancing insulin sensitivity.

Two hundred eighty-eight male Nicholas Large White turkey poults were used to determine the effect of supplementing turkeys with chromium propionate (Cr Prop) from 1 to 84 d of age on performance and animal safety. Treatments consisted of Cr prop supplemented to provide 0, 0.2, or 1.0 mg Cr/kg diet. One mg of supplemental Cr is 5 times (x) the minimal concentration of Cr Prop that enhanced insulin sensitivity in turkeys. Each treatment consisted of 8 floor pens with 12 poults per pen. Turkeys were individually weighed initially, and at the end of the starter 1 (d 21), starter 2 (d 42), grower 1 (d 63), and grower 2 phase (d 84). On d 85, blood was collected from the wing vein in heparinized tubes from 2 turkeys per pen for plasma chemistry measurements. A separate blood sample was collected from the same turkeys in tubes containing K2EDTA for hematology measurements. Turkey performance was not affected by treatment during the starter 1 phase. Gain was greater (P = 0.024) and feed/gain lower (P = 0.030) for turkeys supplemented with Cr compared with controls during the starter 2 phase. Over the entire 84-d study turkeys supplemented with Cr had greater (P = 0.005) ADG and tended (P = 0.074) to gain more efficiently than controls. Gain (P = 0.180) and feed/gain (P = 0.511) of turkeys supplemented with 0.2 mg Cr/kg did not differ from those receiving 1.0 mg Cr/kg over the entire 84-d study. Feed intake was not affected by treatment. Body weights of turkeys supplemented with Cr were heavier (P = 0.005) than controls by d 84. Chromium supplementation did not affect hematological measurements and had minimal effect on plasma chemistry variables. Results of this study indicates that Cr Prop supplementation can improve turkey performance, and is safe when supplemented to turkey diets at 5x the minimal concentration that enhanced insulin sensitivity.

This study was conducted to determine the effect of supplementing turkey diets with chromium propionate (Cr Prop) on Cr concentrations in tissues consumed by humans. Nicholas White male day-old poults were used in this study. Treatments consisted of 0, 0.20, or 1.0 mg supplemental Cr/kg diet. Each treatment consisted of 8 replicate floor pens with 12 poults housed per pen. Diets were fed ad libitum for 84 d. At the end of the study, 2 turkeys per pen were euthanized and samples of liver, breast muscle, kidney, and skin with adhering fat were collected from a similar location in each bird for Cr analysis. Orthogonal contrasts were used to compare the 2 Cr supplemented treatments to the control (0 added Cr) and 0.20 mg Cr to 1.0 mg Cr/kg diet. When expressed on a DM or wet tissue basis, liver (P = 0.001) and muscle (P = 0.015) Cr concentrations were greater in turkeys supplemented with Cr compared with controls. Chromium concentrations in liver were also greater (P = 0.001) in turkeys supplemented with 1.0 mg Cr/kg than those receiving 0.20 mg Cr/kg. Concentrations of Cr in kidney and skin + fat were not affected by treatment. Considering the adequate intake of Cr established for humans, supplementation of Cr Prop at up to 1.0 mg Cr/kg diet would have minimal effect on total Cr intake by humans.

Chromium propionate (Cr Prop) was recently approved by the US FDA for supplementation to horse feed at a level not to exceed 4 mg Cr/horse/day. This approval was based on the ability of Cr Prop to improve insulin sensitivity in adult horses following oral consumption of grain or intravenous administration of glucose, and also on the safety of Cr Prop when supplemented to horse diets at up to 2 times the FDA approved level. The objective of the current study was used to determine the safety of Cr Prop based on health, body weight (BW) gain, body condition score, and blood chemistry and hematological parameters when supplemented at levels of 0, 2, 4, or 8 mg Cr/day. Forty-eight registered Quarter horses were used in this study. The study was conducted as 4 trials, due to a limitation of individual stalls at the testing facility. Horses were housed individually and fed twice daily an oat-based concentrate mix at a rate of 0.2 kg/100 kg BW, and grass hay (2 kg/100 kg BW). Supplemental Cr was provided in 50 g of ground corn/day that was top dressed on the morning feeding of concentrate. In the fourth trial, 12 horses (n = 3/treatment) were bled before feeding on d 0 and 28 of the trial for blood chemistry and hematological measurements. Serum was analyzed for an Equine Chemistry panel, that consisted of calcium, phosphorus, magnesium, sodium, potassium, chloride, bicarbonate, osmolality, anion gap, glucose, urea, total protein, albumin, bilirubin, alkaline phosphatase, aspartate aminotransferase, and creatine kinase. A sample of whole blood also was obtained for a variety of hematological measurements. Each horse served as its own control, because d 28 blood data were statistically analyzed using d 0 blood values as a covariate. Feeding Cr Prop for 42 d did not affect health, body weight gain, or body condition score. Control horses had lower (P ≤ 0.05) RBC counts than those fed 8 mg Cr/day, and tended to have lower RBC counts than those receiving 2 (P = 0.07) or 4 (P = 0.06) mg Cr/day. Other hematological measurements were not affected by dietary Cr. Serum clinical chemistry parameters measured were not affected by treatment. The present study indicates that Cr Prop is safe when supplemented to horses at up to 2 times the FDA approved feeding level.

Forty-eight Quarter Horse geldings (3–8 yr of age) were used to determine the effects of dietary chromium (Cr), in the form of Cr propionate (Cr Prop), on insulin sensitivity. Horses were blocked by age, body condition score, and glucose response to concentrate feeding on d 0, and randomly assigned to treatments. Treatments consisted of 0, 2, 4, or 8 mg Cr/d from Cr Prop. Horses were fed daily a concentrate mix at a rate of 0.2 kg/100 kg BW and grass hay at 1.75 to 2.0 kg/100 kg BW. After an overnight fast, jugular blood samples were obtained at 0, 2, and 4 h after concentrate feeding on d 0 and 28 for determination of glucose and insulin. Plasma glucose on d 28 was affected (P < 0.05) by treatment, time, and treatment x time. Horses fed 4 mg Cr/d had lesser (P < 0.05) plasma glucose concentrations than those in the other treatments at 0 h. At 2 h post feeding glucose concentrations were greater (P < 0.05) in control horses than in those given 4 mg Cr. Horses fed 2 mg Cr/d had lesser (P < 0.05) plasma glucose at 4 h post feeding compared to controls. Plasma glucose did not differ among horses receiving 2 or 4 mg Cr/d at 2 or 4 h. Insulin concentrations were greater (P < 0.05) in horses fed 0 or 2 mg Cr/d than in those given 4 or 8 mg Cr at 0 h. At 4 h post feeding insulin concentrations were greater (P < 0.05) in control horses than in those fed 2 or 4 mg Cr/d. Results of this study indicate that 2 or 4 mg Cr/d from Cr Prop increased insulin sensitivity in adult horses following oral carbohydrate consumption.

Forty-eight Quarter Horse geldings (3 to 8 yr of age) were used to determine the effects of dietary chromium (Cr), in the form of Cr propionate (Cr Prop) on insulin sensitivity. Horses were blocked by age, body condition score, and glucose response to concentrate feeding on day 0 and randomly assigned to treatments. Treatments consisted of 0, 2, 4, or 8 mg Cr/d from Cr Prop. Horses were fed daily a concentrate mix at a rate of 0.2 kg/100 kg body weight (BW) and grass hay at 1.75 to 2.0 kg/100 kg BW. All horses were fed the control diet for 7 d prior to the initiation of the study. After an overnight fast, blood samples from the jugular vein were obtained at 0, 2, and 4 h after concentrate feeding on days 0 and 28 for the determination of glucose, nonesterified fatty acids, and insulin. A glucose tolerance test (GTT) was conducted on day 42. Glucose was infused via jugular vein catheters, and blood samples were collected at various times relative to dosing for glucose and insulin determination. Plasma glucose on day 28 was affected (P < 0.05) by treatment, time, and treatment × time. Horses fed 4 mg Cr/d had lesser (P < 0.05) plasma glucose concentrations than those in the other treatments at 0 h. At 2 h post-feeding glucose concentrations were greater (P < 0.05) in horses fed 0 or 8 mg Cr/d than in those given 4 mg Cr. Horses fed 2 mg Cr/d had lesser (P < 0.05) plasma glucose at 4 h post feeding compared with those fed 0 or 8 mg Cr. Plasma glucose did not differ among horses receiving 2 or 4 mg Cr/d at 2 or 4 h. Serum insulin was affected (P < 0.05) by treatment, time, and treatment × time. Insulin concentrations were greater (P < 0.05) in horses fed 0 or 2 mg Cr/d than in those given 4 or 8 mg Cr at 0 h. At 4 h post-feeding insulin concentrations were greater (P < 0.05) in horses given 0 or 8 mg Cr than in those fed 2 or 4 mg Cr/d. Plasma glucose was affected (P < 0.05) by treatment and time, but not by treatment × time following the GTT. Mean plasma glucose (across sampling times) concentrations were greater (P < 0.05) in controls than in horses fed 2 or 4 mg Cr/d. Glucose concentrations following the GTT did not differ among controls and horses given 8 mg Cr/d. Following glucose infusion, serum insulin concentrations were greater (P < 0.05) in horses fed 2 or 4 mg Cr and tended to be greater in those fed 8 mg Cr/d compared with controls. The results of this study indicate that 2 or 4 mg Cr/d from Cr Prop increased insulin sensitivity in adult horses following oral carbohydrate consumption.

Chromium propionate (Cr Prop) is approved by the U.S. Food and Drug Administration Center for Veterinary Medicine for supplementation to broiler diets up to 0.20 mg Cr/kg diet. A 49-D study was conducted to: 1) determine the safety of Cr Prop when supplemented at 2 and 10 times (×) the approved feeding level over the normal life span of broilers, and 2) determine the effects of supplementing Cr Prop on Cr concentrations of tissues consumed by humans. On day zero, 216 Ross 708 broilers were stratified by weight within sex and randomly assigned to treatments. Dietary treatments were 0 (control), 0.40, and 2.0 mg supplemental Cr/kg diet from Cr Prop. There were 6 replicate cages each of male and female broilers per treatment. At the end of the study blood was collected for determination of plasma biochemical measurements and tissue samples were collected for Cr analysis. Supplementing 0.40 mg Cr/kg diet (2×) did not adversely affect broiler performance, mortality, plasma biochemical measurements or Cr concentrations in breast muscle, skin with adhering fat, or liver. Chromium propionate supplemented at 2.0 mg Cr/kg (10×) did not affect Cr concentrations in breast muscle or skin with adhering fat, but increased (P < 0.05) liver Cr concentrations. Supplementing Cr Prop at 10× the approved feeding level decreased feed intake and gain in male but not female broilers from days 21 to 49. Results of this study support the safety of Cr Prop in broiler diets, and indicate that Cr Prop supplementation to broiler diets at 2 or 10× the approved feeding level does not present a human health concern.

Four hundred crossbred steers were used in a randomized complete block design to investigate the effects of supplemental Zn source and concentration, and dietary Cr on performance and carcass characteristics of feedlot steers fed a steam-flaked corn-based finishing diet. Steers were blocked by initial BW within cattle source (3 sources) and randomly assigned within block to 1 of 5 treatments. Before the initiation of the experiment, trace mineral supplement sources were analyzed for Zn and Cr. Zinc and Cr concentrations of the Zn sources were used to balance all dietary treatments to obtain correct Zn and Cr experimental doses. Treatments were the addition of: 1) 90 mg Zn/kg DM from ZnSO4 and 0.25 mg Cr/kg DM from Cr propionate (90ZS+Cr); 2) 30 mg Zn/kg DM from Zn hydroxychloride and 0.25 mg Cr/kg DM from Cr propionate (30ZH+Cr); 3) 90 mg Zn/kg DM from Zn hydroxychloride and 0.25 mg Cr/kg DM from Cr propionate (90ZH+Cr); 4) 60 mg Zn/kg DM from ZnSO4 and 30 mg Zn/kg DM from Zn methionine (90ZSM); and 5) 90 mg Zn/kg DM from Zn hydroxychloride (90ZH). Steers were individually weighed on d-2 and on 2 consecutive days at the end of the experiment. Initial liver biopsies were obtained from all steers at processing. Equal numbers of pen replicates per treatment were slaughtered at a commercial abattoir on day 162, 176, and 211; individual carcass data and final liver samples were collected. Total finishing dietary Zn and Cr concentrations were 118.4, 58.2, 114.2, 123.0, and 108.2 mg Zn/kg DM and 0.740, 0.668, 0.763, 0.767, and 0.461 mg Cr/kg DM, for treatments 1 to 5, respectively. Data were analyzed statistically using preplanned single degree of freedom contrasts. Steers receiving 90ZH+Cr had greater final BW (P < 0.04) and ADG (P < 0.03) when compared with steers receiving 90ZH. Additionally, hot carcass weight was 8.5 kg greater (P < 0.03) for 90ZH+Cr compared with 90ZH supplemented steers. Steers receiving 90ZH+Cr had greater longissimus muscle area when compared with steers receiving 90ZSM. Dry matter intake, G:F, morbidity and mortality, and all other carcass measurements were similar across treatments. These data indicate that under the conditions of this experiment, Zn source and concentration had no impact on live performance, liver Zn and Cu concentrations, and carcass characteristics. Supplemental Cr in diets containing 90 mg of supplemental Zn/kg DM from ZH improved final BW, ADG, and hot carcass weights.

Chromium (Cr), in the form of Cr propionate, has been permitted for supplementation to cattle diets in the United States at levels up to 0.50 mg of Cr/kg of DM since 2009. Little is known regarding Cr concentrations naturally present in practical feed ingredients. The present study was conducted to determine Cr concentrations in feed ingredients commonly fed to ruminants. Feed ingredients were collected from dairy farms, feed mills, grain bins, and university research farms. Mean Cr concentrations in whole cereal grains ranged from 0.025 mg/kg of DM for oats to 0.041 mg/kg of DM for wheat. Grinding whole samples of corn, soybeans, and wheat through a stainless steel Wiley mill screen greatly increased analyzed Cr concentrations. Harvested forages had greater Cr concentrations than concentrates, and alfalfa hay or haylage had greater Cr concentrations than grass hay or corn silage. Chromium in alfalfa hay or haylage (n = 13) averaged 0.522 mg/kg of DM, with a range of 0.199 to 0.889 mg/kg of DM. Corn silage (n = 21) averaged 0.220 mg of Cr/kg of DM with a range of 0.105 to 0.441 mg of Cr/kg of DM. By-product feeds ranged from 0.040 mg of Cr/kg of DM for cottonseed hulls to 1.222 mg of Cr/kg of DM for beet pulp. Of the feed ingredients analyzed, feed grade phosphate sources had the greatest Cr concentration (135.0 mg/kg). Most ruminant feedstuffs and feed ingredients had less than 0.50 mg of Cr/kg of DM. Much of the analyzed total Cr in feed ingredients appears to be due to Cr contamination from soil or metal contact during harvesting, processing, or both.

The objective of this study was to evaluate the relationships among digestible energy (DE) intake, body weight (BW), and body condition score (BCS) in lean/moderate condition horses. The feed intake of 35 Quarter Horses (age 5.3 +/- 1.2 years; BW 462 +/- 39 kg; BCS 4.5 +/- 0.5) was recorded daily over three, 42-day feeding trials. Horses were offered 1.75-2.00 kg DM/100 kg BW in Orchard grass hay and 0.2 kg/100 kg BW in whole oats. Body weight and BCS were recorded biweekly. Daily DE intake was calculated according to Pagan and recorded as the amount fed minus any refusal. The daily kilogram intake was multiplied by the DE (Mcal/kg) content of the feed to equal the total calories per day. The mean within-horse Delta BW and Delta BCS from 0 to 42 days of each trial were evaluated using paired t tests. Trial 1 horses consumed 24.5 Mcal/d and BW increased (P < .001) by 24 +/- 3 kg; however, there was no significant change in BCS (0.0 0.5). Trial 2 horses consumed 22.8 Mcal/d and BW increased (P = .009) by 8 +/- 3 kg and BCS tended to increase (P = .06) by 0.5 +/- 0.5. Trial 3 horses consumed 25.7 Mcal/d and BW and BCS increased (P < .001) by 22 +/- 2 kg and 1.0 +/- 0.5, respectively. According to trial, horses required approximately 19, 34, and 18 Mcal/kg of weight gain, respectively. Additional factors affecting weight gain are related to the individual. (C) 2017 Elsevier Inc. All rights reserved.

The objective of this study was to investigate the impact of lipid peroxidation in a dose-dependent manner on performance, health, medical treatment, viability, and oxidative status of nursery pigs. Pigs (n = 2200; BW = 5.95 ± 0.2 kg) were housed in 100 pens with 22 pigs/pen in a RCBD based on initial BW and sex and assigned to 5 dietary treatments. Treatments consisted of corn-soybean meal based diets supplemented with 5% of either control corn oil (FFA = 0.06%, anisidine value = 2.5, peroxide value = 4.8 mEq/kg oil) or corn oil peroxidized with air at 20 L/min at 60°C for 12 d (FFA = 0.35%, anisidine value = 30.4, peroxide value = 162.6 mEq/kg oil). Diets were blended to obtain 0, 25, 50, 75, and 100% degrees of peroxidation. Pigs were fed a 3-phase nursery diet program (7, 13, and 23 d, respectively). Pigs were vaccinated with PRRS and Mycoplasma hyopneumoniae (Mhyo) mixed vaccine at placement and PCV2 and Mhyo combination vaccine at 9 wk of age. Blood samples were collected from 10 light- and 10 heavy-weight pigs per treatment prior to and 14 d after the second vaccine dose to determine serum antibody titers, oxidative stress, and vitamin E concentrations. There were no differences in ADG and ADFI among treatments. Gain:feed decreased linearly with increasing peroxidation (P = 0.02) during the first 20 d and overall (665, 669, 664, 659, 652 g/kg for 0, 25, 50, 75, and 100% peroxidation). Pigs pulled, culled, treated and mortality increased linearly (P < 0.05), while percentage of full-value pigs (98.9, 97.8, 96.6, 95.2 and 95.9%, for 0, 25, 50, 75, and 100% level) decreased linearly (P < 0.05) with increasing peroxidation. Final pen gain, which considers mortality and culls, decreased linearly (P < 0.01) with increasing peroxidation (341, 317, 311, 303, and 305 kg, for 0, 25, 50, 75, and 100% level). Antibody titers to Mhyo and PCV2 increased post-vaccination (P < 0.01) but were not affected by peroxidation. Serum MDA was 19% higher in heavy pigs than light weight pigs (P < 0.01) but was not affected by peroxidation. Total antioxidant capacity and vitamin E concentrations were 10% higher (P < 0.04) in heavy weight pigs (P < 0.03) than light weight pigs and decreased (P = 0.05) linearly (1.24, 1.32, 1.23, 0.99, 1.15 ppm serum vitamin E for 0, 25, 50, 75, and 100% peroxidation) as peroxidation increased. Data indicate a progressively negative impact of lipid peroxidation on pig productivity measured under field population conditions, which was primarily related to increased mortality, number of pigs medicated, and number of pigs that were excessively light.

•Metabolism of Zn from Zn hydroxychloride (ZnOHCl) was compared to Zn sulfate (ZnS04) in growing steers.•Apparent absorption of Zn from ZnOHCl was greater than ZnSO4 in steers fed a corn-cottonseed hull-based diet.•Plasma Zn concentrations were greater in steers fed ZnOHCl at the end of the 40-d study.

The objective of this study was to evaluate the effects of dietary chromium (Cr), as chromium propionate, on measures of insulin sensitivity. Liver and muscle glycogen, and plasma glucose and non-esterified fatty acid (NEFA) concentrations were used as indicators of insulin sensitivity. In total, 288 newly hatched male Ross broilers were divided into 4 dietary treatments consisting of 0 (control diet analyzed 0.43 to 0.45 mg Cr/kg), 0.2, 0.4, or 0.6 mg supplemental Cr/kg diet, resulting in 4 treatments with 9 replicate pens per treatment containing eight birds per pen. At d 21, 2 birds per cage were removed based on the greatest deviation from pen mean BW, resulting in each pen containing 6 birds for the final analyses. Final BW were taken on d 40, and on d 42 two birds from each pen were sampled for plasma NEFA, glucose, and muscle and liver glycogen determination at the initiation and termination of a 22 h fast. The remaining 2 fasted birds were sampled after a 30 min refeeding period. No differences were observed in feed intake, BW gain, or feed efficiency on d 21 or d 40. Liver glycogen tended (P = 0.10) to be greater in Cr-supplemented chicks in the fed state, and muscle glycogen concentrations tended (P = 0.07) to be greater in Cr-supplemented chicks compared with controls following fasting and refeeding. Plasma glucose concentrations were not affected by dietary Cr in the fed, fasted, or refed state. Plasma NEFA levels were not affected by treatment in fed or fasted birds. However, plasma NEFA concentrations were lower (P < 0.01) in chicks supplemented with Cr than in controls following fasting and refeeding, suggesting that Cr increased insulin sensitivity. No differences were detected among birds supplemented with 0.2 or 0.4 mg Cr/kg, and among those receiving 0.4 or 0.6 mg Cr/kg. Results of this study indicate that Cr propionate supplementation of a control diet containing 0.43 to 0.45 mg Cr/kg enhanced insulin sensitivity.

An experiment was conducted to investigate the effects of dietary chromium (Cr) source and concentration on growth performance, carcass traits, and some serum lipid parameters of broilers under normal rearing conditions for 42 days. A total of 252 1-day-old Cobb 500 commercial female broilers were randomly allotted by body weight (BW) to one of six replicate cages (six broilers per cage) for each of seven treatments in a completely randomized design involved in a 2 × 3 factorial arrangement of treatments with three Cr sources (Cr propionate (CrPro), Cr picolinate (CrPic), Cr chloride (CrCl3)) and two concentrations of added Cr (0.4 and 2.0 mg of Cr/kg) plus a Cr-unsupplemented control diet. The results showed that dietary Cr supplementation tended to increase the breast muscle percentage compared with the Cr-unsupplemented control group (P = 0.0784), while Cr from CrPic tended to have higher breast muscle percentage compared with Cr from CrCl3 (P = 0.0881). Chromium from CrPic also tended to increase the breast intramuscular fat (IMF) compared with Cr from CrCl3 (P = 0.0648). In addition, supplementation of 0.4 mg/kg Cr tended to decrease low-density lipoprotein cholesterol (LDL-C) (P = 0.0614). Compared with the control group, broilers fed Cr-supplemented diets had higher triglyceride (TG) (P = 0.0129) regardless of Cr source and Cr concentration. Chromium from CrPro and CrPic had lower total cholesterol (TC) compared with Cr from CrCl3 (P = 0.0220). These results indicate that dietary supplementation of Cr has effects on carcass characteristics and serum lipid parameters of broilers under normal rearing conditions, while supplementation of organic Cr can improve carcass characteristics and reduce the cholesterol content in serum.

As a unique species of equine, the donkey has certain specific variations from the horse. This review highlights the origins of the donkey and how this impacts on its behavior, physiology, and propensity to disease. The donkey is less of a flight animal and has been used by humans for pack and draught work, in areas where their ability to survive poorer diets, and transboundary disease while masking overt signs of pain and distress has made them indispensable to human livelihoods. When living as a companion animal, however, the donkey easily accumulates adipose tissue, and this may create a metabolically compromised individual prone to diseases of excess such as laminitis and hyperlipemia. They show anatomic variations from the horse especially in the hoof, upper airway, and their conformation. Variations in physiology lead to differences in the metabolism and distribution of many drugs. With over 44 million donkeys worldwide, it is important that veterinarians have the ability to understand and treat this equid effectively.

Describing the effects of a carbohydrate-rich diet (CRD) on Haflingers with R309 H glycogensynthase 1 (GYS1) mutation. Haflinger mares heterozygous positive (polysaccharide storage myopathy [PSSM] type 1, n = 7) and negative (control, n = 7) for GYS1 mutation received 6 weeks of CRD and hay only (hay), with a wash out period of two. Each diet was followed by oral glucose tolerance test (oGTT), submaximal treadmill exercise test (STET), and biopsies of semitendinosus (STm) and gluteus medius (GMm) muscles. Insulin sensitivity was evaluated by oGTT. Plasma creatine kinase, aspartate aminotransferase, lactate dehydrogenase, and lactate were measured before and after STET. Semitendinosus and GMm biopsies were evaluated for distribution of fiber types (1, 2A, and 2X), chronic myopathic changes, and complex Periodic Acid Schiff (cPAS) positive amylase resistant inclusions. One Haflinger of control group had cPAS inclusions indicating PSSM type 2; therefore, it was excluded. In PSSM1 horses, cPAS were found in every STm sample, and in 10 of 14 GMm samples, furthermore, STm samples showed a greater total myopathy score and significantly more type 2A and fewer type 2X fibers compared with controls. There were no significant differences between groups regarding enzyme levels and for oGTT. Diet had no effect on muscle enzyme levels after STET and on cPAS inclusions in PSSM1 group. Glycogensynthase 1 mutation in Haflingers was not accompanied by clinical signs, even after STET. Carbohydrate-rich diet for 6 weeks did not induce clinical signs or increase cPAS inclusions. As PSSM type 2 is a possibility in Haflingers, STm muscle biopsy and cPAS evaluation should be performed if GYS1 gene test is negative.

Detecting user context with high accuracy using smartphone sensors is a difficult task. A key challenge is dealing with the impact of different smartphone positions on sensor values. Users carry their smartphones in different positions such as holding in their hand or keeping inside their pants or jacket pocket, and each of these smartphone positions affects various sensor values in different ways. This paper addresses the issue of poor accuracy in detecting user context due to varying smartphone positions. It describes the design and prototype development of a smartphone position discovery service that accurately detects a smartphone position, and then demonstrates that the accuracy of an existing context aware application is significantly enhanced when run in conjunction with this proposed smartphone position discovery service.