Increase In BW Research Articles

Effect of frame size and time-on-pasture on steer performance, longissimus muscle fatty acid composition, and tenderness in a forage-finishing system.

Angus-cross steers (n = 96; BW = 309 ± 34 kg; 13.5 mo of age) were used to determine the effects of frame size (medium or small) and time-on-pasture (TOP) on meat composition and palatability in a 2-yr study. Finishing steers grazed mixed pastures (bluegrass/white clover; April start) and were slaughtered after 89-, 146-, and 201-d TOP. At 24 h postmortem, carcass traits were collected and a rib from each carcass was obtained for proximate and fatty acid composition, Warner-Bratzler shear force (WBSF), and postmortem proteolysis. In yr 1, postmortem aging treatments included 14 and 28 d, whereas in yr 2, postmortem aging treatments included 2, 4, 7, 14, and 28 d. Increasing frame size of the finishing steers produced greater (P < 0.05) ADG by 0.10 kg, BW by 24 kg, HCW by 14 kg, and ribeye size by 2.65 cm(2). All other carcass, meat composition, and tenderness measures did not differ (P > 0.05) due to frame size or 2-way interaction with TOP. Increasing TOP resulted in quadratic increases (P < 0.01) in BW and HCW. Ribeye area, fat thickness, KPH, marbling scores, quality grades, and yield grades increased (P < 0.001) linearly as TOP increased. Time-on-pasture linearly increased (P = 0.001) palmitic (C16:0) acid, oleic (C18:1 cis-9) acid, SFA, and MUFA in the LM. Both n-6 PUFA, linoleic (C18:2) and arachidonic (C20:4) acids, decreased linearly (P = 0.001) with increasing TOP. Increasing TOP linearly reduced (P = 0.01) concentrations of all n-3 fatty acids in the LM. These changes resulted in a linear reduction (P = 0.01) in n-6 to n-3 fatty acid ratio with advancing TOP; however, the magnitude of the difference was small (1.46 vs. 1.37). At 14 d of postmortem aging, WBSF was lowest (P < 0.001) for 89-d TOP and greatest (P < 0.05) for the 201-d TOP. After 28 d of postmortem aging, WBSF values for 89- and 146-d TOP did not differ (P > 0.05) compared to the 14-d postmortem aging WBSF values. However, in steaks from 201-d TOP, additional postmortem aging to 28 d reduced (P < 0.001) WBSF. In pasture-based beef finishing systems, increasing TOP increases animal age, HCW, fat thickness, and marbling score; however, tenderness of ribeye steaks decreased with advanced TOP such that longer postmortem aging times were required to achieve similar tenderness levels.

The relative influence of prepregnancy weight and gestational weight gain on offspring birth size in Vietnam (620.7)

Maternal and child undernutrition remains an important public health problem. The objective of this research is to examine the relative influence of maternal prepregnancy weight (PPW) and gestational weight gain (GWG) on birth size for 971 singleton live births born to women who participated in a pre‐conceptional micronutrient supplementation trial in Vietnam. Adjusted generalized regression models were used to examine associations with birth weight, BW (mean + SD: 3054 + 400 g); small for gestational age, SGA (22%); and low birth weight, LBW (5%). A 1 SD increase in PPW was associated with a 226 g (95%CI: 220‐231) increase in BW. Similar and independent effects were observed for BW (226 g; 95%CI: 219 – 233) per SD increase in GWG. The relative impact of a 1 SD increase in PPW and GWG were similar for length (0.17 and 0.14 cm), head circumference (0.13 and 0.15 cm) and MUAC (0.15 and 0.14 cm) at birth, respectively. A 1 kg increase in PPW and GWG was also associated with a 9.4% and 9.5% reduction in the risk of delivering a SGA infant and 12% and 15% for LBW, respectively. Women with pre‐pregnancy BMI &lt; 17 kg/m2 (moderate‐severe thinness) or in the lower tertile of GWG had 2.4 – 2.6 times the risk for SGA and 3.9 – 4.6 times the risk for LBW. These findings indicate that programs aimed at improving birth outcomes will have the greatest impact if they address maternal nutrition both before and during pregnancy.Grant Funding Source: Supported by the Micronutrient Initiative &amp; the Mathile Institute for Advancement of Human Nutrition

Postmortem lung volume/body weight standards for term and preterm infants

Assessment of lung growth is a critical component of the perinatal autopsy. Increased lung liquid content may lead to overestimation of lung growth based on (wet) lung weight. In contrast, lung volume is not influenced by intraalveolar lung liquid. Our aim was to establish age-specific reference values for postmortem lung volume/BW in preterm and term infants. We performed a retrospective analysis of fetuses/infants (16-41 weeks' gestation) without (N = 134) or with (N = 79) risk factors for pulmonary hypoplasia. Lungs were inflated at standardized pressure and volumes determined by water immersion method. Lung volume increased 11-fold between 16 and 41 weeks' gestation, concomitant with a 16-fold increase in BW. Mean lung volume/BW remained constant at 33-34 ml/kg between 16 and 31 weeks' gestation and decreased to 23.4 ml/kg at term. Lung volume/BW of infants with severe risk factors (renal anomalies, diaphragmatic hernia) was significantly lower than age-matched standards. In this group, all fetuses/infants diagnosed as having lung hypoplasia by lung volume/BW also had lung hypoplasia LW/BW standards. However, in infants with "softer" risk factors (rupture of membranes, chromosomal anomalies), 5/26 cases diagnosed with lung hypoplasia based on lung volume/BW had normal LW/BW ratios. In these discrepant cases, lung sections showed significant inflammation and edema, likely accounting for increased wet lung weight. In conclusion, we determined age-specific lung volume/BW reference values for preterm and term infants. In selected situations assessment of lung volume/BW may represent a useful complementary tool to LW/BW for postmortem evaluation of lung size.

Piglet birth weight and litter uniformity: Effects of weaning-to-pregnancy interval and body condition changes in sows of different parities and crossbred lines1

Piglet birth weight and litter uniformity were studied in sows of different parities and crossbred lines in relation to: 1) weaning-to-pregnancy interval (WPI) and 2) sow body condition changes (in BW and backfat thickness) during lactation and gestation in sows with a short WPI (≤7d). At the Institute for Pig Genetics (IPG) research farm, individual piglet birth weights and sow body condition (BW and backfat thickness at farrowing and weaning) were measured for 949 TOPIGS20 and 889 TOPIGS40 sows with >4 total born piglets, inseminated between 2003 and 2011. In all analyses, mean piglet birth weight and birth weight SD and CV were corrected for total number born. Total number born was greater in sows with a WPI of 8 to 21 d (+1.2 piglets; n = 72) and >21 d (+0.7 piglets; n = 182), compared with sows with a WPI ≤7 d (P < 0.01; n = 1,584). Mean piglet birth weight was not affected by WPI. Birth weight SD (-23 g) and CV (-1.7%) were lower in sows with a WPI >21 d, compared with sows with a WPI ≤7 d (P < 0.01). Effects of WPI were independent of sow parity. Effects of body condition changes in sows with a WPI ≤7 d were studied separately in TOPIGS20 sows inseminated between 2006 and 2011 (n = 808), and in TOPIGS40 sows inseminated between 2003 and 2008 (n = 747). Sow body condition loss during lactation was not related with subsequent total number born or mean piglet birth weight. Only in TOPIGS20 sows, more BW loss during lactation was related with greater subsequent birth weight SD (β = 0.83 g/kg, P < 0.01; β = 1.62 g/%, P < 0.01). Additionally, more backfat loss during lactation was related with greater subsequent birth weight SD (β = 5.11 g/mm, P < 0.01) and CV (β = 0.36%/mm, P < 0.01), independent of sow parity. Sow BW increase during gestation was negatively related with total number born [TOPIGS20: β = -0.06 and -0.05 piglet/kg BW increase for parity 2 (P < 0.01), and 3 and 4 (P < 0.01), respectively; TOPIGS40: β = -0.04 piglet/kg BW increase (P < 0.01), independent of sow parity]. Sow BW increase during gestation was positively related with birth weight SD [TOPIGS20: β = 0.63 g/kg BW increase (P = 0.01), independent of sow parity]. Sow body condition increase during gestation was not related with mean piglet birth weight. To conclude, this study shows that litter uniformity is compromised by severe sow body condition loss during lactation and improved in sows with a prolonged WPI. These effects are likely related with (insufficient) restoration of follicle development.

Evidence of genetic variability for digestive efficiency in the growing pig fed a fibrous diet

Energy digestibility in the growing pig increases with BW increase and may differ between breeds of pigs or between lines selected on criteria other than digestion. However, little is known about the variability in energy digestibility within a line or a breed of pigs, especially when fibrous diets are fed. For this purpose, 20 Large White castrated male growing pigs originating from four boars (five per boar), and three to four sows per boar, were fed a high dietary fibre (DF) diet (18% NDF) and measured over 10 consecutive weeks (30 to 95 kg BW range) for their apparent faecal energy, nitrogen and organic matter digestibility. Each week, faeces were totally collected over 5 days and the feed dry matter intake over the same days was recorded. All digestibility coefficients increased regularly (P < 0.001) over the experimental periods or with BW increase (+0.6 point/10 kg BW increase for energy); this rate of increase was not affected by boar origin (no interaction; P > 0.05). The digestibility coefficients were affected by boar origin (P < 0.005 for energy), with about 2 points for energy between the extremes (81.7% v. 79.5%), and there was no marked interaction between boar origin and period. These preliminary results suggest the possibility of selecting growing pigs for an increased digestive efficiency when fed high DF diets.

Influence of penicillin on microbial diversity of the cecal microbiota in broiler chickens

Antibiotic growth promoters have been used for growth promotion of chickens in poultry industry since 1940. Recently, concerns have been raised to the use of antibiotic growth promoters in livestock due to development of antibiotic resistance in bacteria. The objective of our study was to investigate the effect of penicillin supplementation in the feed on cecal microbiota of broiler chickens. Two groups (n = 30) of chickens were fed corn-soybean meal diets with and without supplementation of penicillin at the concentration of 55 mg/kg (ANT vs. CON, respectively). At 18 d of age, the ANT group had significantly (P ≤ 0.05) higher mean BW than the CON group (668.6 vs. 570.0 g). Cecal samples of 5 randomly selected birds were pooled from each group and used for genomic DNA isolation and PCR amplification of 16S rRNA gene; 454 pyrosequencing of the amplicons resulted in 7,881 and 11,214 sequence reads for ANT and CON groups, respectively. Phylogenetic analysis indicated that penicillin supplementation in the ANT group resulted in an elevated proportion of phylum Firmicutes from 58.15 to 91.5% and a decreased proportion of phylum Bacteroidetes from 31.1 to 2.96% compared with the CON group. Recent studies conducted in humans, pigs, and mice have shown a similar shift in gut microbiota in obese individuals compared with the lean ones, indicating that this microbial shift could be responsible for the increase in energy harvest and BW. The results of this study suggest that the growth-promoting effect of penicillin supplementation in broilers may be mediated by a similar microbial process.

Vitamin E supplementation in beef finishing diets containing 35% wet distillers grains with solubles: Feedlot performance and carcass characteristics1

Supplementation of vitamin E has indications for improving cattle health, performance, and retail characteristics when included in grain-based diets. This experiment was conducted to determine performance and carcass characteristics of steers fed diets containing wet distillers grains with solubles (WDGS) and supplemented with vitamin E. Steers of mixed Bos indicus and Bos taurus breeding (n = 199; BW = 363 ± 32 kg) were blocked by BW and assigned to 1 of 4 supplemental vitamin E (VITE) treatments [0 (control), 125, 250, and 500 IU·steer(-1)·d(-1)], which were fed for the last 97 d of the feeding period. Two blocks were on feed 129 d, and 3 blocks were fed for 150 d. Steers were fed a dry-rolled corn-based finishing diet with 35% WDGS (DM basis). Individual BW were measured initially, the initial day of vitamin E supplementation, and the day of slaughter. Carcass weights were collected at slaughter, and carcass data were collected after a 36-h chill. Body weight and ADG were not affected by VITE (P ≥ 0.34). There was a tendency for a linear (P = 0.08) increase in carcass-adjusted BW with increasing VITE. Use of carcass-adjusted final BW resulted in a linear increase (P = 0.04) in ADG with increasing VITE. Pre-vitamin E and vitamin E feeding period DMI were not affected (P ≥ 0.24) by VITE, but there was a tendency (P = 0.08) for a linear increase in overall DMI with increasing VITE. No difference (P ≥ 0.29) occurred in G:F measures using BW gains, but G:F using carcass-adjusted BW gains resulted in a trend (P = 0.11) for G:F to increase linearly with increasing VITE. Hot carcass weights tended (P = 0.08) to increase linearly with increasing dietary vitamin E. Vitamin E supplementation resulted in no effects (P ≥ 0.13) on measured carcass characteristics. Calculated yield grades (YG) were also not affected (P ≥ 0.37). However, the distribution of calculated YG resulted in a quadratic effect (P = 0.02) for YG 3 with the control and 500 VITE being greater than the 2 intermediate amounts. However, the percentage of carcasses grading YG 3 or less were not affected by vitamin E supplementation (P = 0.64). No differences were observed in the distribution of quality grades based on marbling scores (P ≥ 0.57). Data from this study suggest that vitamin E supplemented above basal requirements during the last 97 d of the feeding period in finishing diets containing 35% WDGS results in slight to no effect on animal performance or carcass characteristics.

Effects of supplemental copper-methionine chelate and copper-soy proteinate on the performance, blood parameters, liver mineral content, and intestinal microflora of broiler chickens

SUMMARY In this study, we investigated the effect of dietary supplementation of Cu-Met chelate (CuMet) and Cu-soy proteinate (Cu-SP) on the performance, blood parameters, liver mineral content, and intestinal microflora in broiler chickens. A total of 1,008 hatched Ross broiler chickens were randomly assigned to 1 of 6 dietary treatments (T): T1, control; T2, antibiotic (6 ppm of avilamycin); T3, 50 ppm of Cu as Cu-Met; T4, 100 ppm of Cu as Cu-Met; T5, 50 ppm of Cu as Cu-SP; and T6, 100 ppm of Cu as Cu-SP. Each treatment had 3 replicates of 56 birds (28 birds of each sex). During the 4-wk feeding period, the BW increase of birds in the antibiotic treatment was 3.25% and those of birds in the 100 ppm of Cu treatments were 2.67% on average compared with the control group. The production efficiency factor {[livability (%) × live weight (kg)/age (d) × FCR] × 100} was increased by 5.23% for birds in the antibiotic treatment and by 0.7 to 7.8% for birds in Cu treatments, among which the treatment with 100 ppm of Cu as Cu-SP was highest. The red blood cell level, hematocrit level, and mean corpuscular volume of birds in the Cu treatments were lower than were those of birds in the control group. Copper concentration in the liver increased as the level of Cu supplementation increased. The populations of lactobacilli and total bacteria increased, and that of Escherichia coli decreased as the level of Cu increased, whereas all microbes, including Clostridium perfringens, decreased in the antibiotic treatment.

The relation of high fat diet, metabolic disturbances and brain oxidative dysfunction: modulation by hydroxy citric acid

AimsThis study aimed to examine the effect of high fat diet (HFD) to modulate brain dysfunction, and understand the linkages between obesity, metabolic disturbances and the brain oxidative stress (BOS) dysfunction and modulation with hydroxyl citric acid of G. Cambogia.MethodsRats were divided into 3 groups; 1st control, maintained on standard normal rat chow diet, 2nd HFD, maintained on high fat diet along 12 week and 3rd HFD+G, administered G. Cambogia for 4 weeks and each group include 8 rats. Blood, brain and abdominal fat were collected for biochemical measurements.ResultsHFD group showed significant increase in energy intake, final BW and BW gain. Also significant increase in weight of abdominal fat in HFD group. HFD induce metabolic disturbance through increasing the lipid profile (LDL, TG, TC), γGT and α-amylase activity, uric acid level and hyperglycemia, while decreasing creatine kinase (CK) activity.These changes associated with lowering in brain nitric oxide (NO) level and rising in serum butyrylcholinesterase (BChE), brain catalase activity and MDA levels as oxidative stress markers. These alterations improved by G. Cambogia that decrease BOS and increased NO level.ConclusionsRats fed HFD showed, metabolic disturbances produce hyperglycemia, hypertriglyceridemia, hypercholesterolemia and increased LDL associated with increased BOS. Involvement of BuChE, NO and oxidative stress associated with metabolic disturbances in the pathophysiological progression in brain, suggesting association between obesity, metabolic disorders and brain alteration while, using G. Cambogia, ameliorate the damaging effects of the HFD via lowering feed intake and BOS.

Effects of divergent selection for 8-week body weight on postnatal enzyme activity pattern of 3 fiber types in fast muscles of male broilers (Gallus gallus domesticus)

A divergent selection experiment was conducted for 8-wk BW in chickens. At 3, 6, 9, and 12 wk of age, samples of pectoralis profundus (PP) and biceps femoris (BF) muscles from fast-growing and slow-growing lines were used to estimate the enzyme activities and muscle fiber diameter. Microphotometric measurements made in situ of succinate dehydrogenase (SDH, EC 1.3.99.1) and glycerol-3-phosphate dehydrogenase (GPDH, EC 1.1.99.5) were completed on serial sections of PP and BF muscles from male chickens, in order to examine the ratio of SDH:GPDH activity in single fibers. On the basis of the SDH:GPDH activity ratios, muscle fibers were divided using cluster analysis into 3 populations of different fiber types (O = oxidative, OG = oxidative-glycolytic, and G = glycolytic). Cockerels of the SGL attained an 8.1-fold increase and those of the FGL a 6.8-fold increase in BW at 12 wk compared with that at 3 wk of age. The O, OG, and G type fibers of the BF muscles of the SGL had significantly (P ≤ 0.001) lower SDH:GPDH activity ratios than those of the FGL. A step decrease in the SDH:GPDH activity of O, OG, and G fibers in the PP of both lines occurred, and this differed significantly between SGL and FGL (P ≤ 0.001). Age and line effects influenced the diameter of the 3 fiber types in the BF muscle only. In contrast to this response, all 3 fiber types of the PP muscles reached similar diameters in both lines during the growth process from wk 3 to 12. From the results of this study, we concluded that the activities of metabolic enzymes in skeletal muscle fibers are under the influence of muscle type, age, and selection pressure. Microphotometry is a suitable method for the evaluation of enzyme activity measured in a single muscle fiber. The method enables precise estimation of enzyme activities, especially in muscles composed of populations of different metabolic fiber types.

Effects of ad libitum and restricted feed intake on growth performance and body composition of Yorkshire pigs selected for reduced residual feed intake1

Residual feed intake (RFI), defined as the difference in the observed and expected feed intake while accounting for growth and backfat, has gained much attention, but little is known about why pigs selected for reduced RFI are more efficient. To this end, a line of Yorkshire pigs selected for reduced RFI was developed. The objective of this study was to evaluate the 5th generation of this select line against a randomly selected control line for performance, carcass and chemical carcass composition, and overall efficiency toward the later part of the growth phase. Eighty barrows, 40 from each line, were paired by age (~132 d, P < 0.60) and BW (74.8 ± 9.9 kg, P < 0.49) and randomly assigned to 1 of 4 feeding treatments in 10 replicates: 1) ad libitum, 2) 75% of ad libitum, 55% of ad libitum, and BW stasis, with weekly adjustments in intake to keep BW constant for each pig. Pigs were individually penned (group housing was used for selection) and on treatment for 6 wk. Initial BW did not differ between the lines (P < 0.49). The ad libitum select pigs consumed 10% less feed (P < 0.09) than the ad libitum control with no significant difference in BW (P < 0.80) and slight differences in carcass fat composition (P < 0.20) and backfat (P < 0.11), which resulted in significantly less carcass energy (P < 0.03). Under restricted feeding, the select line had an increase in BW (P = 0.10) while consuming the same ration of feed as the control line with no significant difference in chemical carcass composition and lighter visceral weights, which was significant for the 75% of ad libitum treatment (P < 0.01). Under BW stasis feeding the select line consumed 7.6% less feed overall (P = 0.21) and 18% less feed at the end of the 6 wk (P < 0.08), to maintain static BW with no significant difference in chemical carcass composition compared with the control line. Overall, the select line had lighter visceral weight (P < 0.02) and a greater dressing percentage (P < 0.03) compared with the control line. Using regression, the select line had reduced energy retention (P < 0.04) and feed energy utilization (P < 0.34); however, the select line appeared to have reduced maintenance requirements (P < 0.13). In conclusion, selection for reduced RFI decreases feed intake with no significant difference (P > 0.05) in growth performance, reduced backfat, increased dressing percentage, and reduced maintenance requirements. All of these traits are appealing to the producer and result in increased profits in the production setting.

Lower Dose Prednisone Prevents Radioiodine-Associated Exacerbation of Initially Mild or Absent Graves’ Orbitopathy: A Retrospective Cohort Study

Radioiodine (RAI) therapy may cause progression of mild or absent Graves' orbitopathy (GO), preventable by oral prednisone. Optimal doses of prednisone are undefined. The aim of this study was to compare the effectiveness of reported doses [starting dose, >0.3 mg/kg body weight (bw)], and lower (<0.3 mg/kg bw)] doses of prednisone. We conducted a retrospective matched cohort study at a University Center. Of 111 RAI-treated Graves' patients with mild or no GO, 35 received no steroid prophylaxis (absence of GO and/or risk factors for RAI-associated GO progression); 28 received low-dose prednisone (starting dose, 0.16-0.27 mg/kg bw; mean +/- sd, 0.22 +/- 0.03 mg/kg bw; group 1); and 48 received higher doses (group 2). Among the latter, 28 (starting dose, 0.32-0.56 mg/kg bw; mean +/- sd, 0.36 +/- 0.05 mg/kg bw) were matched with group 1 according to several relevant variables. Prednisone was started 1 d after RAI and withdrawn after 6 wk. We assessed ocular changes (1, 3, and 6 months after RAI) and side effects of prednisone. Two of 35 patients not receiving steroid prophylaxis (6%) developed mild-to-moderate GO (clinical activity score, 2/7 and 3/7) after RAI. No patients in group 1 or group 2 had GO progression. Side effects were very mild and inconstant, although more frequent in group 2. Both groups showed an increase in bw, an increase that was significantly higher in group 2. Lower doses of oral prednisone (about 0.2 mg/kg bw) are as effective as previously reported doses (0.3-0.5 mg/kg bw). A shorter treatment period (6 wk) is probably sufficient. The increase in bw is less using lower doses of prednisone.

Effects of wheat middlings and choice white grease in diets on the growth performance, carcass characteristics, and carcass fat quality in growing-finishing pigs (2010)

A total of 288 pigs (PIC TR4 × 1050, initially 93.3 lb) were used in an 87-d study to determine the effects of wheat middlings and choice white grease (CWG) on growth performance, carcass characteristics, and carcass fat quality of growing-finishing pigs. Pens of pigs were randomly allotted by initial weight and gender (4 barrows and 4 gilts per pen) to 1 of 6 dietary treatments with 6 replications per treatment. Treatments were arranged in a 2 × 3 factorial arrangement with the main effects of added wheat middlings (0 or 20%) and CWG (0, 2.5, or 5%). Dietary treatments were corn-soybean meal-based diets with 15% dried distillers grains with solubles (DDGS) and fed in 4 phases. There were no CWG x wheat middlings interactions (P ≥ 0.12) for any of the criteria evaluated. Overall, (d 0 to 87) adding 20% dietary wheat middlings decreased (P < 0.001) ADG and worsened (P < 0.001) F/G. Pigs fed diets with increased dietary CWG had increased (quadratic, P < 0.03) ADG and improved (linear, P < 0.01) F/G. Pigs fed diets containing 20% wheat middlings had decreased (P < 0.01) final BW; while there was a numerical increase in final BW (P < 0.09) as dietary fat was increased.

The effect of rumen degradable and rumen undegradable intake protein on feedlot performance and carcass merit in heavy yearling steers1

A total of 432 crossbred yearling steers (395 kg +/- 6.35) were used in a randomized block experiment to study the effects of rumen degradable intake protein (DIP) and rumen undegradable intake protein (UIP) concentration on feedlot performance and carcass merit. The 6 dietary treatments used for this study included 1) a 10.5% CP diet with 5.1% UIP and 5.4% DIP (DIP5); 2) an 11.5% CP diet with 5.1% UIP and 6.4% DIP (DIP6); 3) a 12.5% CP diet with 5.1% UIP and 7.4% DIP (DIP7); 4) a 13.5% CP diet with 5.1% UIP and 8.4% DIP (DIP8); 5) a 14.5% CP diet with 5.1% UIP and 9.4% DIP (DIP9); and 6) a 14.5% CP diet with 6.1% UIP and 8.4% DIP with the additional UIP provided by corn gluten meal. There was a linear increase in final BW and ADG and a trend for a linear increase in DMI associated with increasing DIP concentration within the 5.1% UIP treatments. Feed efficiency and NE recovered from the diet were not influenced by dietary DIP concentration. As dietary DIP concentration increased, carcass fat depth and average yield grade increased linearly and the percentage of yield grade 1 and 2 carcasses decreased linearly. Dietary UIP treatment had no effect on final BW, ADG, DMI, G:F, and calculated NE recovery. For the 14.5% CP diets, marbling score tended to be reduced for steers fed 6.1% UIP as compared with 5.1% UIP. The remaining carcass traits were not affected by dietary UIP. The results of this study show that the DIP requirement in the finishing diet for heavy yearling steers fed steam-flaked corn is greater than 7.4% of dietary DM but likely is not more than 8.4% of dietary DM when dietary UIP is approximately 5.1% of dietary DM. Increasing UIP above 5.1% of dietary DM did not improve feedlot performance or HCW. Expressed on a CP basis, it appears as though the requirement for CP for heavy yearling steers fed steam-flaked corn-based finishing diets is 13.5% of DM, with approximately 62% of CP from DIP.

Trends in birth size and macrosomia in Queensland, Australia, from 1988 to 2005

The objectives of this study were to explore temporal changes in birth measures in Queensland, Australia, and examine whether secular trends are similar to those in other countries. This study used data from the Queensland Perinatal Data Collection, including singleton livebirths (n = 831 375) from 1988 to 2005. Recorded birthweight (BW, g), birth length (BL, cm), gestational age (weeks), maternal age, ethnic origin and calculated ponderal index (PI, kg/m(3)) were used. Temporal trends were assessed over the intervals 1988-2005 for BW and 2001-2005 for BW, BL and PI. Mean BW increased during the 17-year interval by approximately 1.9 g/year at a relatively low rate compared with reports from other countries. The proportion of high BW infants (> or = 4000 g) rose by 0.8% per year. Stratification by Indigenous status indicated that the increase in mean BW and prevalence of high BW was confined to non-Indigenous newborns only. The secular increase in BW was further modified by gestational age, and maternal age. The increase in BW was larger in term infants (4.2 g/year) than in preterm infants (1.8 g/year), and larger in infants of younger mothers than in those of older mothers (5.0 g/year vs. 3.1 g/year). There were no trends in mean BL and mean PI at birth from 2001 to 2005. In Queensland, mean BW increased moderately in the last 17 years, as did the proportion of high BW infants. The trend in rising BW remained after controlling for other perinatal characteristics. Birth measures per se and related trends differed by Indigenous status and warrant further investigation.

Effect of extended withdrawal of zilpaterol hydrochloride on performance and carcass traits in finishing beef steers1

The objective was to evaluate the effects of an extended withdrawal period after feeding the beta-adrenergic agonist zilpaterol hydrochloride (ZH) for 20 d at the end of the feeding period. Three hundred eighty-four crossbred beef steers were blocked by BW and randomly allocated into 64 pens (6 steers/pen). Pens were assigned to treatments in a 2 x 4 factorial arrangement in a randomized complete block design. Main effects were the addition of 0 (control) or 8.3 mg/kg of ZH (DM basis) to the finishing diet for 20 d before estimated average slaughter date and paired withdrawal periods of 3, 10, 17, or 24 d before slaughter. Individual BW were measured initially, 1 d before ZH feeding, and 1 d before slaughter. The ZH feeding period was initiated so that control cattle in the 3-d withdrawal group would be expected to average 65% USDA Choice Quality grade and have 1.27 cm of 12th-rib fat based on visual appraisal. Carcass data were collected at slaughter. For the 3-d withdrawal steers, 2 steers from each pen were selected to determine visceral organ and total offal mass at slaughter. The ZH x withdrawal day interaction was not significant (P > 0.10) for the majority of variables. There was no difference (P > or = 0.12) due to ZH feeding for final BW, carcass-adjusted final BW, or ADG. However, DMI was decreased (P = 0.02) and G:F increased (P = 0.01) in steers fed ZH vs. control steers. As day after withdrawal of ZH increased, there was a linear increase (P < 0.001) in final BW and carcass-adjusted final BW, but a linear decrease (P < 0.001) in ADG over the finishing period and over the ZH plus withdrawal period. Overall, HCW was 380 and 369 kg (P < 0.001) for ZH and control steers, respectively. However, the difference between ZH and control was 14, 17, 5, and 6 kg with 3, 10, 17, and 24 d withdrawal, respectively (ZH x withdrawal day, P = 0.09). Feeding ZH increased dressing percentage (65.8 vs. 64.6%; P < 0.001) and LM area (94.8 vs. 89.7 cm(2); P < 0.001), and decreased calculated yield grade (2.69 vs. 2.91; P = 0.03) and percentage of cattle grading USDA Choice (31.1 vs. 42.3%; P = 0.03) compared with controls. Small intestinal mass (g/kg of empty BW) was greater (P = 0.03) for steers fed ZH compared with controls. There were no other differences (P > or = 0.11) in mass of body components, expressed in kilograms or as a fraction of empty BW. In this experiment, improvements in animal performance and HCW due to feeding ZH were generally maintained when withdrawal was extended through 10 d.

The Azorean Loligo forbesi (Cephalopoda: Loliginidae) in captivity: transport, handling, maintenance, tagging and survival

The population of Loligo forbesi inhabiting the Azorean Archipelago achieves the largest size ever reported for this species but also for any Loliginidae. Despite their importance as a food source for local communities, very little is known about their biology and ecology. In this paper, we describe our efforts in capturing, transporting, handling, tagging and holding wild adult L. forbesi in the laboratory. Three culture trials were conducted in the Island of Faial, Azores. Over 84 squid were captured by jigging, transported in separate containers and placed in a recirculating seawater system composed of three 3.6 m circular tanks (8000 l capacity each). Drawings and technical details about the system (filtration system, tanks, liners, illumination, flow rates, etc.) as well as water quality parameters (ammonia, nitrite, nitrate, iron, pH, salinity and temperature) are presented. By keeping squid in separate bags and providing constant water flow, no mortality occurred during transport from fishing ground to the laboratory. Mean survival time for each trial was 8 days (1503 g mean weight), 17 days (595.1 g mean weight) and 11 days (826.1 g). A small female remained alive for 44 days. In this system, mortality was faster for larger squid. Low survival time could be attributed to bad water quality management, namely high ammonia levels and high temperature variations but also restricted swimming space for larger squid (>1000 g). Pin tags proved to be the most adequate method of distinguishing between individuals. Squid were fed a variety of fish species, either fresh or defrosted. Daily feeding rates varied between 0 and 7.8% body weight (BW day−1). Most squid lost weight or did not grow. However, some individuals showed a positive increase in BW, varying between 0.009 and 1.4% increase in BW day−1. Key factors to take into account for increasing laboratory survival are: (1) catching squid with jigs; (2) prevention of skin damage during transport; (3) maintenance of small individuals; (4) segregating sexes to reduce agonistic interactions; (5) providing good water quality; and (6) abundant food supply.

Reducing bias in maintenance energy expected progeny difference by accounting for selection on weaning and yearling weights1

Maintenance energy requirements of cattle can be predicted from published equations utilizing metabolic BW and milk production potential. Metabolic BW is a function of BW at a constant fat percentage or BCS. Pedigree and performance records can be used in random regression models to predict genetic merit for metabolic BW and milk production potentials. The purpose of this study was to present a methodology for predicting mature cow maintenance energy EPD using mature cow BW and BCS and accounting for prior selection of replacement females at weaning and yearling ages. Variance components were obtained for direct and maternal effects on weaning weight, direct effects on postweaning BW gain, and direct coefficients for random regression on mature weights (MW) adjusted for BCS. These BW were transformed into metabolic BW by taking BW to the power of 0.75, variance components were estimated for metabolic BW, and were then used to predict breeding values from which cow maintenance energy EPD could be derived. Data used in this analysis were obtained from the Red Angus Association of America and limited to herds with MW and corresponding BCS observations. The data set included 52,338 BW records on 21,103 individuals. Weaning and yearling contemporaries to those with MW observations, but with no MW records themselves, were included to account for selection occurring before maturity. Heritability estimates for weaning weight direct, weaning weight maternal, and postweaning BW gain were 0.18 +/- 0.02, 0.16 +/- 0.02, and 0.18 +/- 0.02, respectively. Mature BW observed at 2, 3, 4, 5, and 6 yr of age had heritability estimates of 0.45 +/- 0.03, 0.44 +/- 0.03, 0.49 +/- 0.03, 0.66 +/- 0.04, and 0.62 +/- 0.05, respectively. Correlations between weaning weight direct and MW ranged from 0.65 +/- 0.07 to 0.82 +/- 0.04, and correlations between MW at different ages ranged from 0.95 +/- 0.03 to 0.99 +/- 0.01. The genetic correlations between postweaning BW gain and MW ranged from 0.48 +/- 0.06 to 0.59 +/- 0.06. The 15-yr genetic increase in metabolic BW was 3.6 kg(0.75), greater than the value of 0.23 kg(0.75) obtained from the same data ignoring weaning and yearling contemporaries with unobserved MW, the approach currently used in the derivation of cow maintenance EPD published by the Red Angus Association of America.

Compatibility of a Combination of Tiamulin and Chlortetracycline with Salinomycin in Feed During a Pulsed Medication Program Coadministration in Broilers

In an earlier study, the continuous medication of broiler feed with a combination of tiamulin (TIA; 20 mg/kg), chlortetracycline (CTC; 60 mg/kg), and the ionophore anticoccidial salinomycin (SAL; 60 mg/kg) caused an initial increase in BW and feed efficiency (FE; g of weight gain/kg of feed intake). However, as doses increased to combinations of 30 mg/kg of TIA and 90 mg/kg of CTC or 50 mg/kg of TIA and 150 mg/kg of CTC, there was a dose-related reduction in growth rate and FE. This was thought to be due to the interaction between TIA and SAL. In this study, using a protocol similar to the previous trial, broiler chicks were administered SAL at 60 mg/kg via the feed and the same inclusion rates of TIA + CTC. However, instead of feeding the birds continuously, considering the cost of TIA and possibly to compensate for the depressed growth attributable to the interaction with SAL, they were pulse-dosed for 1 to 10 d and again at 21 to 27 d, and the whole trial lasted 35 d to see if the intermittent pulses might reduce production losses. A total of 200 straight-run 1-d-old broiler chicks (Hubbard classic) were randomly distributed into 4 groups, with each group consisting of 5 cages containing 10 birds. The 20 cages were allocated to the 4 treatment groups on a random basis. The control diet, containing only SAL at 60 mg/kg, was fed to all birds throughout the 35-d trial, including the period during the gaps between dosing (i.e., d 11 to 20 and d 28 to 35). Feed and water were available for the whole trial period. Several serum enzymes (creatine kinase, lactate dehydrogenase, and aspartate aminotransferase) were determined from blood samples taken on d 35. Blood samples were also collected at 1, 19, and 35 d of age and were examined for antibody titers to Mycoplasma gallisepticum and Mycoplasma synoviae. Necropsy and histopathology of the birds (n = >or=4) were conducted during weekly intervals. There was no significant difference in weight gain, feed intake, and FE when the groups treated with TIA + CTC were compared with the control group (P > 0.05). There was no relationship between mortality and inclusion rates of the medication. No clinical signs of an interaction were exhibited during the trial, which was supported by necropsy and serum enzyme results. Maternally derived antibodies against M. gallisepticum were identified at the start of the trial but disappeared within 19 d, and infection with M. gallisepticum or M. synoviae was found neither serologically nor clinically during the trial. The results demonstrated that intermittent pulse administration of TIA at 50 mg/kg + CTC at 150 mg/kg from d 1 to 10 and d 21 to 27, along with continuous feeding of SAL (60 mg/kg), would be possible without altering performance and while maintaining the health status of the broilers. However, further research is required on the presence of artificial infections with Mycoplasma pathogens to determine the efficacy of the combination of TIA +CTC.

Ganho de peso e características de carcaça de bovinos Nelore castrados ou não-castrados terminados em confinamento

Objetivou-se avaliar o ganho de peso e as características de carcaça de bovinos Nelore, castrados ou não-castrados, terminados em confinamento. Utilizaram-se 36 animais com 24 meses de idade e peso vivo médio inicial de 445,30 (não-castrados) ou 449,57 kg (castrados aos 400 kg de peso corporal). Os animais foram abatidos aos 50 dias de confinamento, quando atingiram peso vivo médio de 516,30 (não-castrados) e 506,86 kg (castrados). Os animais não-castrados não tiveram aumento no peso vivo final, mas apresentaram maior ganho de peso (1,42 e 1,15 kg). Os pesos de carcaça quente (272,77 e 261,89 kg) e carcaça fria (266,13 e 258,24 kg) não diferiram entre animais não-castrados e castrados. Animais não-castrados apresentaram maior rendimento de carcaça quente (52,88 vs 51,65% para os não-castrados), todavia, o rendimento de carcaça fria foi similar entre os grupos (51,55 e 52,39%), em virtude da menor quebra ao resfriamento nos animais castrados (2,43 e 1,40%). Os pesos absolutos de traseiro especial (133,07 e 131,55 kg), dianteiro (105,65 e 100,09 kg) e ponta-de-agulha (27,41 e 26,60 kg) não diferiram entre animais não-castrados e castrados, mas os pesos relativos de traseiro dos animais castrados foram maiores que dos não-castrados (50,93 vs 50,00%). O contrafilé dos animais não-castrados foi mais pesado que o dos castrados (8,41 vs 7,90 kg). A espessura de gordura (2,05 vs 2,21 mm) e a área de olho-de-lombo (66,98 vs 67,48 cm²) não diferiram entre animais não-castrados e castrados. O pH na carcaça fria em tempos predeterminados até o estabelecimento do rigor mortis também é semelhante entre animais não-castrados e castrados. Animais não-castrados e castrados têm peso de carcaça satisfatório, porém não apresentam acabamento mínimo de 3 mm de gordura, quando confinados por 50 dias com dieta à base de cana-de-açúcar e concentrado. Para adequação do acabamento, a dieta dos animais deve ser balanceada com maior nível energético.