BW Loss Research Articles

Acute Changes in Body Composition in Runners Participating in a 100 Mile Footrace

PURPOSE: Determine if: 1) dual energy x-ray absorptiometry (DEXA), bioelectrical impedance spectroscopy (BIS) and bioelectrical impedance analysis scale (S) can be used interchangeably as accurate surrogate measurements of % body fat (%BF) and % total body water (%TBW) before and after a 100 mile footrace; 2) If % body mass (%BM) change is an accurate indicator of %TBW change during such exercise. METHODS: BM was measured using S without shoes in running clothes. %TBW and %BF were obtained before and after the race using the S, DEXA and BIS sequentially. RESULTS: Pre-race %BF and %TBW values among 18 runners were not different for the three measurement techniques and correlation coefficients (Pearson's r) showed positive associations among all three measurement techniques. Post-race comparison measures in 10 runners (6 finishers; 4 non-finishers covering 30-62 miles) revealed significant differences in mean (±SD) %BF with BIS (12.0 ± 5.4) vs. DEXA (18.7 ± 3.6; p<0.05) and vs. S (18.2 ± 4.8; p<0.05) and in %TBW with BIS (64.1 ± 4.0) vs. DEXA (56.7 ± 4.1; p<0.05) and vs. S (59.6 ± 3.5; p<0.05). Significant correlations in post-race measurements were noted only between BIS and DEXA in %BF (r=0.81; p<0.05) and in %TBW (r=0.80; p<0.05). However, Bland-Altman plots revealed DEXA values measuring consistently higher than BIS values in %BF with a mean difference between the two averages of 3.6 and limits of agreement (LOA) between +5.4 and -12.6. Similarly, Bland-Altman plots for %TBW revealed a mean difference of 2.4 with BIS measuring consistently higher than DEXA and LOA between +9.4 and -4.6. Mean %BM loss during the race of 1.6 ± 2.3 was not significant. Mean percent decrease (D) in %BF with DEXA (-0.5 ± 0.6), BIS (-4.1 ± 4.6) and S (-1.0 ± 1.0), and mean percent increase (D) in %TBW with DEXA (0.4 ± 1.2), BIS (2.7 ± 3.8) and S (0.7 ± 0.7) were not significantly different between techniques with high ±SD's. CONCLUSIONS: DEXA, BIS and S can be used interchangeably to measure %BF and %TBW in steady-state (pre-race) conditions but are not accurate surrogate measures in non-steady-state (post-race) scenarios. %BW loss during a 100 mile footrace cannot be solely attributed to changes in %TBW and therefore other changes in body composition (%BF) should be factored into consideration. Sponsored by Western States Endurance Run Foundation and ImpediMed™

Use of crude glycerol, a biodiesel coproduct, in diets for lactating sows1,2

An experiment was conducted to evaluate the effect of dietary crude glycerol in lactating sow diets on sow and litter performance under heat stress conditions. Mixed parity (range = 0 to 13) sows (n = 345; 253 +/- 24 kg of BW) were assigned randomly within gestation housing location and parity to 1 of 4 dietary treatments. Treatments consisted of a corn-soybean-based control diet (CON) and 3, 6, or 9% glycerol added at the expense of corn and soybean meal. Liquid crude glycerol was incorporated in the complete diet at the time of mixing. Dietary treatments were imposed on d 109 of gestation (2.25 kg/d) when sows were moved into farrowing rooms. Heat index during lactation in farrowing rooms exceeded 25 degrees C for all sows. At farrowing, sows were allowed ad libitum access to feed throughout lactation. Dietary treatment tended (P = 0.08) to influence ADFI of sows (CON = 6.04 kg/d; 3% = 6.21 kg/d; 6% = 5.69 kg/d; 9% = 6.00 kg/d; pooled SE = 0.18). Up to 9% crude glycerol in the diet had no effect on sow BW and backfat loss, weaning-to-estrus interval, preweaning mortality of piglets, and ADG of piglets. Increasing dietary glycerol linearly reduced (P = 0.10) litter size at weaning (CON = 9.50; 3% = 9.60; 6% = 9.36; 9% = 9.39; pooled SE = 0.08). Daily water consumption was not affected by dietary treatment. Crude glycerol did not affect respiration rates or rectal body temperatures, indicating no efficacy in reducing heat stress of sows. Plasma glycerol concentrations increased linearly (P < 0.05) as dietary crude glycerol increased (CON = 1.21 microM; 3% = 1.69 microM; 6% = 7.21 microM; 9% = 29.04 microM; pooled SE = 1.58), but plasma glucose concentrations were not affected. Crude protein content of the milk of sows was not affected (P = 0.16) by dietary treatment. Dry matter (P = 0.07) and crude fat (P = 0.09) content of the milk of the sows tended to increase linearly (DM basis: CON = 17.84%; 3% = 18.43%; 6% = 18.98%; 9% = 18.48%; pooled SE = 0.34; crude fat: CON = 4.78%; 3% = 4.91%; 6% = 5.50%; 9% = 5.24%; pooled SE = 0.30), whereas milk ash concentration tended (P = 0.09) to decrease linearly with increasing dietary glycerol (CON = 0.77%; 3% = 0.79%; 6% = 0.74%; 9% = 0.74%; pooled SE = 0.02). Increasing dietary crude glycerol linearly increased (P < 0.05) lactose concentration in the milk of sows (CON = 5.16%; 3% = 5.30%; 6% = 5.43%; 9% = 5.46%; pooled SE = 0.10). Results from this study indicate that lactating sows fed diets containing up to 9% crude glycerol perform similarly to sows fed a standard corn-soybean meal diet.

Evaluation of limit feeding corn and distillers dried grains with solubles in non-feed-withdrawal molt programs for laying hens

An experiment was conducted using 504 Hy-Line W-36 Single Comb White Leghorn hens (69 wk of age) randomly assigned to 1 of 7 treatments. These treatments consisted of a 47% corn:47% soy hulls diet (C:SH) fed ad libitum; a 94% corn diet fed at a rate of 36.3, 45.4, or 54.5 g/hen per day (CORN 36, CORN 45, and CORN 54, respectively); and a 94% corn distillers dried grains with solubles (DDGS) diet fed at the same rates as the previous corn diets (DDGS 36, DDGS 45, and DDGS 54, respectively) during the molt period of 28 d. The intent was to feed the DDGS diets for 28 d; however, all hens on these diets had very low feed intakes and greater than anticipated BW loss. Thus, they were switched to a 16% CP corn-soybean meal layer diet on d 19 of the molt period. At d 28, hens on all treatments were fed the same corn-soybean meal layer diet for 39 wk (73 to 112 wk of age). All DDGS diets and the CORN 36 diet resulted in total cessation of egg production during the molt period and egg production of hens fed the CORN 45, CORN 54, and C:SH diets had decreased to 3 and 4%, respectively, by d 28. Body weight loss during the 28-d molt period ranged from 14% for the CORN 54 diet to approximately 23% for the 3 DDGS diets. Postmolt egg production (5 to 43 wk) was higher for hens fed the DDGS molt diets than those fed the corn diets. There were no consistent differences in egg mass, egg-specific gravity, feed efficiency, or layer feed consumption among molt treatments for the postmolt period. These results indicate that limit feeding corn diet and DDGS diet in non-feed-withdrawal molt programs will yield long-term postmolt performance that is comparable to that observed by ad libitum feeding a C:SH diet.

Plasma ghrelin concentrations of beef cattle consuming a similar amount of dietary energy supplied by different ingredients1

Previous research demonstrated increased plasma ghrelin concentrations in beef cattle when intake of a high-grain diet was restricted. Two experiments were conducted to determine whether differences in DMI influenced plasma ghrelin concentrations when energy intake was similar but cattle were in either an anabolic or a catabolic state. In Exp. 1, five steers (BW = 592.6 +/- 9.3 kg) were offered dietary treatments of 1) 50:50 hay:concentrate (HY) to meet the NE(m) requirement and were supplied an additional 3.4 Mcal of NE(g) daily, 2) or a diet composed of 10:90 hay:concentrate but were limit-fed to achieve an energy intake similar to that of the HY steers (LFC). The LFC treatment met the NE(m) requirement of each steer and supplied 3.6 Mcal of NE(g) daily. The experiment was conducted as a crossover design composed of 2 21-d periods. In the first period, 2 steers were assigned to the HY treatment and 3 steers were assigned to the LFC treatment. On d 21 after initiation of the dietary treatment, serial blood samples were collected via indwelling jugular catheter, using periods of frequent sampling in which samples were collected at 15-min intervals. The periods of frequent sampling were spread throughout the beginning, middle, and end of the 12-h feeding interval. After the first period, steers were weighed, dietary treatments were switched between steer groups, and intake amounts were recalculated on the basis of the first-period ending BW. The second-period adaptation and sampling were repeated as described for the first period. Plasma samples were assayed for ghrelin, insulin, GH, and NEFA concentrations. Experiment 2 was conducted using the same methodology as Exp. 1, except that steers were in a catabolic state. Five steers (BW = 718.3 +/- 12.8 kg) were offered the HY or LFC diet at an amount that would supply 80% of the NE(m) required to maintain BW. For Exp. 1, energy intake was sufficient to result in similar (P = 0.14) BW gains between treatment groups. Experiment 2 energy intake resulted in a loss of BW that was similar (P = 0.66) between treatment groups. In both experiments, the decreased energy density of the HY diet resulted in greater (P < or = 0.001) DMI for HY steers compared with LFC steers. Regardless of catabolic or anabolic state, plasma ghrelin, GH, and insulin were similar (P > or = 0.44) when energy intakes were similar despite differences in DMI between HY and LFC steers. Plasma NEFA concentrations were similar (P > or = 0.45) between treatment groups in an anabolic state but tended to differ (P = 0.09) as a result of treatment for cattle in the catabolic state. These data are consistent with the hypothesis that quantity of DMI does not influence plasma ghrelin concentrations of steers when energy intake is similar.

Use of dietary thyroxine as an alternate molting procedure in spent turkey breeder hens

In the turkey industry, molting is traditionally achieved by reducing photoperiod and withdrawing feed and water for several days. Although it is the most effective method, this practice is discouraged in Canada and alternative strategies need to be established. Thyroid hormone levels naturally change during molt, and dietary thyroxine (T4) supplementation was previously shown to induce molt in chickens. This study aimed at evaluating the effectiveness of supplemental dietary T4 in inducing molt in spent turkey breeder hens. One hundred twenty 75-wk-old hens were randomly divided into 4 groups (5 floor pens/replicates, 5 hens each) with the control group kept under a 14-h photoperiod and fed a breeder's diet throughout, whereas hens from the 3 other groups were supplemented with 40 ppm (45.76 mg/kg) T4 for 10 d. One treatment group was maintained under 14 h of light and fed a breeder's diet, whereas the 2 others were subjected to a drop in photoperiod to 6 h during or after supplementation and then were fed a maintenance diet. Egg production, feed intake, BW, molt, and plasma levels of T4, prolactin, and luteinizing hormone were measured. All treated hens ceased laying by d 20; however, several individuals spontaneously returned to lay when left on 14 h of light, suggesting incomplete involution of the reproductive tract. Supplementation significantly reduced feed consumption and induced rapid BW loss. All hens returned to their initial weight by the end of the experiment. Most treated hens initiated molt by d 8 of supplementation and all completed molt by d 37. Plasma T4 in treated hens increased significantly by d 3 (P < 0.05) and remained significantly higher than in controls until d 9 (P < 0.01). Levels returned to initial values by d 35. Prolactin levels did not appear to be influenced by T4 but were mainly dependent on photoperiod and reproductive stage, whereas luteinizing hormone levels remained low throughout. In summary, dietary supplementation with 40 ppm (45.76 mg/kg) T4 was successful in inducing molt in turkey breeder hens. However, dropping the photoperiod was necessary to completely reset the reproductive system.

Effect of weaning date (normal vs. late) on performance of young and mature beef cows and their progeny in a fall calving system in the Southern Great Plains1

Data from 158 predominantly Angus fall-calving beef cows were used in 4 consecutive years to determine the effects of weaning date and cow age class on cow and calf performance. Treatments were arranged in a 2 x 2 factorial with 2 weaning dates and 2 age classes (young cows <or=3 yr and mature cows >or=4 yr). Weaning dates were 1) normal weaning in mid-April at 210 d of age (NW) and 2) late weaning in mid-July at 300 d of age (LW). Mature cows were heavier (P < 0.01) than young cows throughout the trial, although BCS was similar (P >or= 0.10) among cow age classes. Cow BW (P = 0.58) and BCS (P = 0.40) were similar among weaning treatments at NW; however, at the beginning of the calving season, NW cows were heavier (585 vs. 562 kg; P = 0.02) and had greater BCS (6.57 vs. 5.95; P < 0.0001) than LW cows. Postpartum BW and BCS losses were greater (P < 0.0001) for NW cows, resulting in similar BW (P = 0.56) and BCS (P = 0.07) at the beginning of the breeding season and until April. Progeny of NW cows were 2.4 kg heavier (P < 0.01) at birth and grew faster before the April weaning date, resulting in increased BW (8 kg; P < 0.05) at the time of normal weaning. This increase in BW gain may be partially explained by the increased milk production of NW cows (0.59 kg/d as measured in February; P < 0.05). Although NW calves had increased BW in April, LW calves were heavier in July because of increased ADG during the weaning interval (1.13 vs. 0.8 kg; P < 0.0001). A cow age class x weaning date interaction (P = 0.007) was detected for pregnancy rate. Pregnancy rates were greater (P < 0.10) for LW-mature cows (96.7%) and NW-young cows (98.4%) than for LW-young cows (89.3%). However, pregnancy rate of NW-mature cows (90.2%) did not differ (P = 0.12) from that of LW-mature or LW-young cows, but was less than that of NW-young cows. These findings indicate that producers may benefit from matching weaning date to cow age class. It appears more advantageous to delay weaning of calves born to dams 4 yr or older while maintaining NW for dams 3 yr or younger at the time of calving. Late weaning had no detrimental effects on the performance of mature cows.

Adaptability of pregnant Merino ewes to the cold desert climate in Nevada1

Grazing ability is difficult to record in animals under free-ranging conditions without sophisticated methods. Alternatively, grazing ability may be indirectly inferred from changes in BW and production characteristics during the grazing period. The present study investigated the effect of grazing on resource-limited rangelands on BW, wool characteristics, and offspring weaning weights in nine hundred five 5/8, 7/8, and fullblood Merino ewes of 2 to 7 yr of age during a grazing period of approximately 2.5 mo (between January and March). A total of 469 ewes gave birth to a single lamb, 248 to twin lambs, and 188 did not give birth. Body weights were measured and wool samples taken before and after the ewes were allowed to graze freely on the rangelands; absolute change in BW and change in BW as a percentage of initial BW were estimated. On average, grazing on resource-poor rangelands resulted in BW loss, a reduction in fiber diameter and its CV, and increased staple length. Animals with finer wool at the start of the grazing period lost phenotypically (r = -0.07, P < 0.05) and genetically (r = -0.23, P < 0.05) less BW during the grazing period and had a greater probability to carry 1 lamb (or 2) to term (P < 0.05). Animals that lost less BW produced more greasy fleece (r = 0.09, P < 0.01). Body weight change did not significantly influence offspring weaning weights. Change in BW was moderately heritable at h(2) = 0.29; fiber diameter was strongly heritable at h(2) = 0.51. Animals with the least inclusion of Merino genetics lost more BW (P < 0.01) during the grazing period and had a more uniform fiber diameter (P < 0.05) but shorter staples (P < 0.05) and less fleece (P < 0.0001) than animals with a greater level of Merino genetics. Our results indicate that animals with finer wool appeared to be better adapted to the cold Nevada desert. Thus, selection for finer wool may positively influence adaptability to resource-limited cold climate conditions; alternatively, BW change may be selected for directly. Because nutritional deficiencies during pregnancy can have adverse consequences for the offspring, indirect selection for grazing ability would foremost result in healthier ewes that can produce lambs and wool without compromising their welfare.

Utilizing fungus myceliated grain for molt induction and performance in commercial laying hens

Molting in poultry is used to rejuvenate hens for a second or third laying cycle. Feed withdrawal was once the most effective method used for molt induction; however, it has being phased out due to food safety and animal welfare concerns. This study evaluated the utilization of fungus myceliated grain as a safe and effective alternative for inducing molt, enhancing immunity, reducing Salmonella growth, and returning to egg production. Laying hens were subjected to 1 of 5 treatments: 1) nonfed (NF), 2) full-fed (FF), 3) fungus myceliated meal (FM), 4) 90% fungus myceliated meal + 10% standard layer ration (FM-90), and 5) 90% alfalfa meal + 10% fungus myceliated meal (AF-90). Each treatment condition was replicated 9 times during a 9-d molt period. The results revealed that egg production for treatments 1 and 3 ceased completely by d 5, whereas hens in treatments 4 and 5 ceased egg production by d 6. The percentage of BW loss decreased significantly (P < 0.05) in treatments 1 (57%), 2 (8%), 3 (35%), 4 (37%), and 5 (44%). Ovary weights of hens fed all molting diets decreased significantly from the full-fed control but did not differ significantly (P < 0.05) from each other. Salmonella population in the crop, ovary, and ceca from hens differed significantly (P < 0.05) among treatments. Return to egg production differed between treatments with higher production beginning in treatment 3 and ending in treatment 5. Antibody titers did differ (P < 0.05) among treatments. From these results, fungus myceliated meal appears to be a viable alternative to conventional feed withdrawal and other methods for the successful induction of molt and retention of postmolt performance.

Effects of Chopping on Utilization of Sorghum Stover by Nubian Goats

Effects of chopping sorghum stover (Tabat variety) on Dry Matter Intake (DMI), apparent digestibility and body weight changes in Nubian goats were studied in the Gezira, Sudan. The chemical composition of the stover (%) was 96.78±0.83, 1.43±0.02, 4.65±0.39, 42.98±0.01, 9.99±0.89 and 40.96±1.24 for DM, EE, CP, CF, ash and NFE, respectively. Dry matter intake on different basis was higher for the chopped stover and the effect was significant (p<0.05) as g/d (606 for the long and 687 for the short). Chopping decreased losses in BW, but not significantly. It was (kg/week) 0.616 for the long and 0.366 for the short. Chopping increased nutrients apparent digestibilities and the effect was significant (p<0.05), except for CF and EE. They were 55.20, 59.11, 18.60 and 41.78 and 67.89 for DM, OM, CP, EE and CF, respectively for the long and 65.87, 68.15, 45.28, 53.90 and 72.47, respectively for the short.

Performance and profitability of second-cycle laying hens as influenced by body weight and body weight reduction during molt

An experiment was conducted to determine the effects of hen BW before molt and the percentage of BW loss during molt on the subsequent performance and profitability of hens during the second cycle of production. Results revealed that profits associated with Light hens (≤ 1,453 g, or 3.2 lb) were from 1.8¢ to 3.8¢/dozen eggs higher than those associated with Heavy hens (≥ 1,589 g, or 3.5 lb). Profits of Nonselected hens (ranging from 1,090 to 2,134 g, or 2.4 to 4.7 lb) were intermediate, ranging from 1.2¢ to 2.5¢/dozen higher than profits of Heavy hens. The increased profitability of Light hens was largely due to their improved feed conversion. Because Light hens produced predominantly Large and Extra Large eggs, the price spread between Medium and Large eggs had little impact on profits. Although not as pronounced as the effect of premolt BW, profits associated with Heavy hens that underwent a 35% reduction in BW during molt were from 0.8¢ to 1.5¢/dozen higher than those from Heavy hens with a 25% BW reduction. Reducing the BW of Light hens by 35% had no observable adverse effects in this study.

Bovine myofiber characteristics are influenced by postweaning nutrition

This study determined the extent to which bovine longissimus lumborum muscle (LLM) myofibers are influenced by nutrition for 120 d from weaning and the time-course of recovery after severe postweaning nutritional restriction. After weaning, 3 groups of Belmont Red cattle, a tropically adapted breed, were fed to achieve rapid growth (RG, > or =0.6 kg of BW gain/d; n = 16), slow growth (SG, 0.2 kg of BW gain/d; n = 17), or BW loss (WL, 10% loss of weaning weight; n = 17) over 120 d. They were then grazed as 1 group at pasture with forage supplementation for 600 d until slaughter at approximately 500 kg of BW. Samples of LLM were taken from 8 to 12 animals per treatment 6 d before (baseline) and 115, 204, 324, and 476 d after commencement of the study and from all cattle at slaughter (d 721). Myofiber characteristics were determined by immunocytochemical staining of myosin heavy chains. Cross-sectional areas (CSA) of the major myofiber types 1, 2A, and 2X in WL were reduced at d 115 compared with baseline and with the growth groups (all P < 0.001); however, there was little difference in the percentage of the different myofiber types (all P > 0.10). Differences in CSA of the major myofiber types between WL and the growth groups at 115 d were smallest for type 1 (slow oxidative) and greatest for type 2X (fast glycolytic). Consequently, the relative area (percentage of total myofiber area) of type 1 myofibers in WL was significantly greater at 115 d than in the growth groups (P < 0.001). During recovery from postweaning nutritional restriction, significant differences in major myofiber type percentages were not evident (all P > 0.10), and by 721 d CSA of myofiber types differed little between the treatment groups, although SG had greater CSA of type 1 (P < 0.05) and type 2A (P < 0.01) myofibers than WL and RG. At 721 d, the relative area of type 2A myofibers was less in WL compared with SG (P < 0.01) and RG (P < 0.05) and of type 2X myofibers greater (P < 0.05) in WL compared with SG. It is concluded that in the LLM of cattle undergoing severe nutritional restriction immediately postweaning, the size of the more glycolytic fiber types is more adversely affected than the more oxidative types, resulting in an increased relative area of type 1, slow oxidative myofibers. However, given adequate time and nutriment at pasture, LLM myofiber characteristics of cattle recovered to near normal after severe, chronic nutritional restriction immediately postweaning, consistent with earlier findings for beef quality.

Body weight loss in beef cows: I. The effect of increased β-oxidation on messenger ribonucleic acid levels of uncoupling proteins two and three and peroxisome proliferator-activated receptor in skeletal muscle

Twenty-six Angus-cross cows were studied during BW loss (WL) and BW maintenance (WM) to examine the effects of elevated beta-oxidation on mRNA levels of NEFA-responsive signaling molecules in skeletal muscle. At the end of the WL and WM sampling periods, muscle biopsies were removed from the biceps femoris and mRNA levels were measured using real-time PCR. In comparison with WM, cows undergoing WL had elevated mRNA levels of carnitine palmitoyltransferase 1 (4.6-fold), fatty acid binding protein 3 (2.0-fold), and acyl-coenzyme A oxidase 1 (2.8-fold), all of which are indicators of beta-oxidation. Levels of mRNA of the NEFA-responsive signaling molecules PPAR alpha, delta, and gamma increased 2.0-fold, 2.2-fold, and 1.84-fold, respectively, during WL. Uncoupling proteins 2 and 3 also had increased mRNA (3.0-fold and 6.0-fold, respectively) during WL, but Western blot analysis found no changes in protein abundance of uncoupling protein 3. Uncoupling protein expression can be directly stimulated by elevated NEFA, potentially to protect cells from damage by lipid oxidation by-products. Thus, an increase in mRNA levels of genes involved in beta-oxidation of fatty acids and fatty acid by-products occurs during BW loss in beef cattle. These data support previous findings in nonruminants and suggest that these genes play a role in the same physiological processes in ruminants.

Body weight loss in beef cows: II. Increased antioxidant messenger ribonucleic acid levels in skeletal muscle but not erythrocyte antioxidant activity

Twenty-six Angus-cross cows were used to examine the effect of BW loss (WL) on skeletal muscle and erythrocyte markers of oxidative stress. Serum NEFA concentrations, erythrocyte superoxide dismutase, and glutathione peroxidase activities were measured during WL and BW maintenance. Real-time reverse-transcription-PCR was used to determine mRNA levels of antioxidant genes during both periods to assess skeletal muscle response to WL. Body weight loss resulted in elevated serum NEFA concentrations but no change in erythrocyte superoxide dismutase and glutathione peroxidase activities. During WL, mRNA levels of the antioxidant genes glutathione peroxidase 4, mitochondrial superoxide dismutase, thioredoxin reductase 1, and selenoprotein W increased. Abundance of mRNA of genes involved in antioxidant signaling, specifically, PPARgamma coactivator-1 alpha, nuclear respiratory factor 1, estrogen-related receptor alpha, and tumor protein 53, was also increased. In summary, during WL cows had no change in peripheral antioxidant enzyme activity, but mRNA abundance of proteins involved in protecting the body from oxidative stress increased in skeletal muscle. During times when NEFA are used as a fuel source, signals such as mild reactive oxygen species production or increased concentration of lipid by-products activate the transcription of nuclear signaling molecules such as PPARgamma gamma coactivator-1 alpha, nuclear respiratory factor 1, estrogen-related receptor alpha, and tumor protein 53. These genes work to activate antioxidant genes such as mitochondrial superoxide dismutase, glutathione peroxidase 4, and thioredoxin reductase 1 to aid in the detoxification of reactive oxygen species. These data suggest an important role for antioxidant genes to protect cattle that are mobilizing body fat.

Hypoxia factors and cytokines mRNA expression in visceral and subcutaneous adipose tissues (VAT and SCAT) in obese insulin resistant dogs. Effects of weight loss and fenofibrate treatment.

Expansion of VAT and SCAT has been described to be associated with adipocyte hypoxia. That could lead to inflammation and insulin resistance (IR), but the link with obesity remains unclear. Our aim was to assess the expression of hypoxia and inflammation markers in VAT and SCAT, in obese IR dogs, and the effect of BW loss or fenofibrate treatment, which both improve insulin sensitivity.VAT and SCAT biopsies were taken from dogs in 3 different times: (a) when dogs were obese (group 1), (b) after they had been given fenofibrate (10 mg/kg BW) for 15 d (group 2) and (c) after they had been given a hypoenergetic diet and had recovered their ideal BW (group 3). mRNA expression of HIF‐variants 1, 4, 7, 8, HIF‐1A, IL‐1B, TNF‐A, IL‐1A, ubiquitine ligase and very long chain fatty acid (VLCFA) ligase‐5 was quantified using real time RT‐PCR.Fenofibrate did not affect BW (‐3%). Hypoenergetic diet resulted in a 25% BW lost. In VAT, mRNA expression was lower in groups 2 and 3, except IL‐1A and VLCFA‐ligase‐5. In SCAT, mRNA expression of only HIF‐1variant1 and VLCFA‐ligase‐5 was lower in the group 3 compared to group 1.These results confirm different metabolic responses in SCAT and VAT. They show a dramatic decrease in hypoxia factors expression in VAT in dogs after weight loss as well as at the end of the 15‐d fenofibrate treatment. This was concomitant to a decrease in cytokine expression, that could explain the improvement in insulin sensitivity.

Effects of malic acid on feed intake, milk yield, milk components and metabolites in early lactation Holstein dairy cows

The objective of this study was to evaluate the effects of malic acid (MA) on feed intake, milk yield and composition, blood metabolites and energy balance in early lactation Holstein dairy cows from 1 to 63 day in milk (DIM). Twenty-eight multiparous Holstein dairy cows, blocked by lactation number, previous 305-d mature equivalent milk production, and expected calving date, were arranged into four groups in a randomized block design. Treatments were: control (without MA), LMA, MMA and HMA with 70, 140 and 210 g malic acid per cow per day, respectively. The supplement of food grade MA (99.8% of MA) was hand-mixed into the top one-third of the daily ration. Cows were fed ad libitum a total mixed ration consisting of equal proportion of forage and concentrate. Milk yield increased ( P = 0.04), but feed intake and milk components were not affected ( P > 0.05) by MA supplementation. The energy balance, expressed as the difference between energy input and output, tended to be higher ( P = 0.08) for MA supplemented cows during the 63-DIM period MA and supplemented cows showed a trend ( P = 0.07) toward less loss of BW during the 63-day period, especially during the first 21-day of lactation. Concentrations of plasma glucose and serum insulin were higher for cows fed LMA, MMA, and HMA relative to control and linearly ( P < 0.01) increased with increasing MA supplementation. Concentrations of non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA) and urine ketones were lower for MA-supplemented cows at 7, 14 and 21 DIM of lactation and linearly ( P < 0.01) decreased with increasing MA supplementation. Although feed intake was not affected, milk yield increased, MA-supplemented cows experienced higher concentrations of plasma glucose and serum insulin, lower concentrations of plasma BHBA and NEFA, and lower concentrations of urine ketones, suggesting that nutrient digestibilities and energy availability may have been improved.

Ideal amino acid balance for sows during gestation and lactation1

Improving efficiency of protein utilization is important for pregnant sows under restricted feed allowance and for lactating sows with limited feed intake. Sows have limited ability to support the growth of fetuses and mammary glands during late gestation and to support mammary growth and milk production, especially during first lactation period. A series of studies was conducted to characterize requirements and ideal ratios of AA for 1) fetal growth, 2) mammary gland growth of gestating sows, 3) maternal tissue gain of gestating sows, 4) mammary gland growth of lactating sows, and 5) maternal tissue gain of lactating sows. A total of 97 pregnant sows and their fetuses and a total of 174 lactating sows and their nursing piglets were used for these studies to collect fetal tissues, mammary tissues, and maternal tissues for AA analysis. Requirements and ideal ratios of AA for sows changed dynamically depending on stages of pregnancy. Suggested daily requirements for true ileal digestible Lys were 5.57 and 8.78 g, and relative ideal ratios for Lys:Thr:Val:Leu (on basis of AA weight) were 100:79:65:88 and 100:71:66:95 for d 0 to 60 and d 60 to 114 of gestation, respectively. Requirements and ideal ratios of AA for lactating sows changed dynamically depending on potential amounts of protein mobilization from maternal tissues, which are related to voluntary feed intake and milk production. Suggested ideal ratios for Lys:Thr:Val:Leu were 100:59:77:115 and 100:69:78:123 if BW losses of sows during 21 d of lactation are 0 and 33 to 45 kg, respectively. To optimize efficiency of dietary protein utilization by sows, the dietary AA content and ratios can be adjusted by stages of pregnancy (i.e., phase feeding) and by expected feed intakes or parities of sows during lactation (i.e., parity-split feeding) considering the dynamic changes in the requirements and ideal ratios of AA.

Effects of glycerol on lactation performance, energy balance and metabolites in early lactation Holstein dairy cows

The objective was to evaluate effects of glycerol supplementation on feed intake, milk yield and milk composition, blood metabolites and energy balance in Holstein dairy cows from 4 to 63 days in milk (DIM). Thirty-six multiparous cows, blocked by lactation number, previous 305 day mature equivalent milk production and expected calving date, were arranged into four groups in a randomized block design. Treatments were: control (without glycerol), glycerol-low (LG), glycerol-medium (MG) and glycerol-high (HG) with 100, 200 and 300 g glycerol per cow per day, respectively. The supplement of food grade glycerol (0.998 g/g glycerol) was hand-mixed into the top one-third of the daily ratio. Cows were fed ad libitum a total mixed ratio consisting of equal proportions of forage and concentrate. Feed intake, milk yield and its components were not affected by glycerol supplementation. The energy balance, expressed as differences between energy input NE I and output (NE M + NE L) in MJ per cow per day, was higher ( P < 0.04) as glycerol supplementation level increased, especially during the first 17 and last 20 days of the 63 day period. Glycerol-supplemented cows tended ( P < 0.06) toward less loss of BW, especially first 17 and last 20 days of the 63 day period. Concentrations of glucose in plasma were higher for cows fed glycerol relative to control (54.1 mg/dL versus 58.1 mg/dL, respectively) and linearly increased ( P < 0.01) with increasing glycerol supplementation level. Concentrations of non-esterified fatty acids, beta-hydroxybutyrate and urine ketones were lower for glycerol-supplemented cows at 7, 14 and 21 days of lactation and linearly ( P < 0.01) decreased with increasing glycerol supplementation. Although milk yield and feed intake were not affected, glycerol-supplemented cows has a more positive energy status (higher concentrations of plasma glucose, lower concentrations of plasma beta-hydroxybutyrate, lower concentrations of urine ketones), suggesting that net energy availability may have been increased.

The Effect of Mushroom and Pokeweed Extract on Salmonella, Egg Production, and Weight Loss in Molting Hens

An experiment was conducted to evaluate the effects of mushroom and pokeweed extract alone or in combination with alfalfa meal on Salmonella spp. population, egg production, and weight loss in laying hens during a 10-d molting period. The trial used 54 active laying hens approximately 77 wk of age that were naturally infected with Salmonella spp. The layers were subjected to 1 of 9 treatment groups, replicated 3 times with 2 hens per replicate cage. The treatment conditions were as follows: 1) full-fed + H(2)0 (FFW), 2) full-fed + mushroom (FFM), 3) full-fed + pokeweed (FFP), 4) nonfed + H(2)0 (NFW), 5) nonfed + mushroom (NFM), 6) nonfed + pokeweed (NFP), 7) full-fed alfalfa meal + H(2)0 (FFAW), 8) full-fed alfalfa meal + mushroom (FFAM), and 9) full-fed alfalfa meal + poke-weed (FFAP). The results showed that the base-10 logarithm values of Salmonella from the ceca significantly increased (P <or= 0.05) in treatment NFW (3.48), NFM (3.22), and FFAW (3.33), whereas the greatest reduction was observed in treatment FFAM (2.72). The number of Salmonella bacteria recovered from the crop was significantly greater in the NFW treatment (3.43) and lowest in treatment FFAM (2.62). Treatment FFAM (30.0%) had the lowest BW loss and differed significantly from treatment NFW (42.3%), NFM (39.7%), and NFP (41.5%) but not from FFAW (38.0%) and FFAP (34.0%). Ovary weights for treatments NFW, NFP, FFAM, and FFAP did not differ significantly from each other but did so for NFM and FFAW (38.0%), which had the lowest weight. Return to egg production at 2 mo lagged behind in treatments FFAM, NFP, and FFM more than in any other treatments. At 3 mo, treatments FFAAM and NFW differed from the other treatments. Findings indicate that a greater decrease in the natural Salmonella population in the ceca and crop can be obtained with the combination of full-fed alfalfa plus mushroom extract in molting hens and induce a comparable molt with feed withdrawal.

Effect of drinker type on water intake and waste in newly weaned piglets1

During the first few days after weaning, pigs often experience BW loss as they adapt to eating solid food. During this time period, they are also known to drink excessively and develop abnormal oral behavior such as belly nosing. The excessive drinking may stem from the piglets' attempt to satiate hunger through gut fill from a familiar ingestive source. Gut fill through water intake may affect the establishment of feeding behavior. Using drinker devices other than the standard nipple drinker may ease the piglets' transition at weaning by facilitating the initiation of feeding and preventing the development of behavioral problems such as excessive drinking and belly nosing. In this experiment, we examined the effect of drinker type on water and food intake, growth rates, and belly nosing in newly weaned piglets. Eighteen pens of 15 piglets each (270 piglets total) were weaned at 18.1 +/- 0.1 d of age and housed in pens containing 1 of 3 drinker devices (standard nipple, push-lever bowl, and float bowl). Piglets' water and feed intake, water use, BW, and behavior were examined on a pen basis through 2 wk after weaning. Piglets with nipple drinkers wasted more water than the other piglets (P < 0.001; float, 295 +/- 70 mL x pig(-1) . d(-1); nipple, 1,114 +/- 63 mL x pig(-1) . d(-1); and push-lever, 186 +/- 63 mL x pig(-1) . d(-1)), whereas piglets with float bowls consumed less water than the other piglets (P < 0.001; float, 475 +/- 81 mL . pig(-1) x d(-1); nipple, 870 +/- 76 mL x pig(-1) . d(-1); push-lever, 774 +/- 76 mL x pig(-1) . d(-1)). Drinker type affected feeding behavior (P = 0.02); piglets with push-lever bowls spent less time at the feeder than the other piglets, although no difference was detected for feed intake (P = 0.64) or overall ADG (P = 0.16). Piglets with push-lever bowls also tended to perform less piglet-directed nosing behavior than piglets with the float bowl (P = 0.04). Piglets appear to use more water during the first 2 d after weaning with certain drinker devices. However, piglets do not appear to attain satiety through water consumption because most of the water used during the first few days after weaning is wasted. This excessive drinking and water wastage can be abated through the use of push-lever drinkers without negative implications for feed intake or growth rates.

Energy balance, leptin, NEFA and IGF-I plasma concentrations and resumption of post partum ovarian activity in swedish red and white breed cows

In the purpose to provide further information in respect of the relationship between metabolism and post partum (PP) ovarian activity resumption in dairy cows, the aim of the present study was to characterize the energy balance (EB) and leptin, NEFA and IGF-I plasma levels in Swedish Red and White (SRW) cows with and without ovarian activity re-initiation within 7 weeks PP. The study was conducted on 12 primiparous SRW cows fed the same diet as total mixed ration for ad libitum intake. The EB was calculated weekly from parturition until seven weeks PP. Blood samples were collected weekly from one week before until 7 weeks after calving for leptin, NEFA and IGF-I analysis. For progesterone (P4) analysis, blood samples were collected two times per week from parturition until the end of the study. P4 profile was used in addition to the clinical examination to detect cows with and without ovarian activity resumption. The clinical and ultrasonographic examination, coupled with P4 profile analysis showed the resumption of ovarian activity within 7 weeks after calving in 8 (group A) and no ovarian resumption in 4 cows (group B). No significant differences were detected in the whole period of observation in the amount of milk production between the two groups, while the mean milk protein content was significantly lower in group B at the third week PP. The calculated EB was negative in both groups in the first three weeks after calving, but more marked in group B. NEFA and Leptin plasma levels did not show significant differences between the two groups. In conclusion, the results of the present study showed that, when low milk producing primiparous cows are concerned, no significant differences in BW loss, milk yield, EB and leptin and NEFA plasma levels between the cows with and without resumption of ovarian activity within 7 weeks post partum were seen. However, significantly higher IGF-I levels in the first two weeks after calving were found in cows with post partum ovarian activity resumption, highlighting the important role of IGF-I as sensitive signal between metabolism and reproduction.