An overview of the major phenomena of the localization of sound sources by normal-hearing, hearing-impaired, and aided listeners

Localizing a sound source requires the auditory system to determine its direction and its distance. In general, hearing-impaired listeners do less well in experiments measuring localization performance than normal-hearing listeners, and hearing aids often exacerbate matters. This article summarizes the major experimental effects in direction (and its underlying cues of interaural time differences and interaural level differences) and distance for normal-hearing, hearing-impaired, and aided listeners. Front/back errors and the importance of self-motion are noted. The influence of vision on the localization of real-world sounds is emphasized, such as through the ventriloquist effect or the intriguing link between spatial hearing and visual attention

Evaluating the efficacy of a novel phytase source

Citation: Flohr, J. R., DeRouchey, J. M., Tokach, M. D., Dritz, S. S., Woodworth, J. C., & Goodband, R. D. (2016). Evaluating the efficacy of a novel phytase source. Journal of Animal Science, 94, 111-112. doi:10.2527/msasas2016-236A total of 350 nursery pigs (PIC 1050 barrows, initially 15.1 kg BW) were used in a 21-d study to determine the available phosphorus (aP) release curve for a novel phytase product (Microtech 5000, VTR Bio-tech Co., Guangdong, China). Pigs were randomly allotted to pens at arrival to facilities and on d 0 of the trial pens were allotted to 1 of 7 treatments in a randomized complete block design. There were 5 pigs per pen and 10 pens per treatment. Pigs were fed corn-soybean meal-based diets formulated to contain 1.25% SID Lys. Experimental treatments consisted of 3 diets formulated to 0.12, 0.18, and 0.24% aP with the only source of added P being an inorganic source (monocalcium P). Then, phytase was added to the diet formulated to 0.12% aP at 4 levels (250, 500, 750, and 1000 FTU/kg). Diets were analyzed for phytase using the AOAC method, and analyzed concentrations were lower than formulated. Diets formulated to contain 250, 500, 750, and 1000 FTU/kg had analyzed concentrations of 155, 335, 465, and 780 FTU/kg, respectively. On d 21, one pig per pen was euthanized and fibulas were collected to determine bone ash weight and percentage bone ash. From d 0 to 21, increasing P from inorganic P or increasing phytase increased ADG (linear, P < 0.01), G:F (linear, P < 0.01 for inorganic P; quadratic, P < 0.03 for phytase), and final BW (linear, P < 0.01). Bone ash weight and percentage were increased (linear, P < 0.01) with increasing inorganic P and increasing phytase. Response criteria, which remained in the linear portion of the quadratic phytase curve (ADG, bone ash weight, and percentage bone ash), were used to calculate aP release curves. When analyzed phytase values and percentage bone ash are used as the predictor variables, aP release percentage for up to 780 FTU/kg of Microtech 5000 phytase can be predicted by the equation (y = 0.000002766761x– 0.000000002225x2– 0.000201841391; r2 = 0.948), where x is the phytase concentration in the diet (FTU/kg)

Development of equations to predict the influence of floor space on average daily gain, average daily feed intake, and gain-to-feed ratio of finishing

Citation: Flohr, J. R., Woodworth, J. C., Tokach, M. D., Dritz, S. S., DeRouchey, J. M., & Goodband, R. D. (2016). Development of equations to predict the influence of floor space on average daily gain, average daily feed intake, and gain-to-feed ratio of finishing. Journal of Animal Science, 94, 7-7. doi:10.2527/msasas2016-015Data from existing literature examining the influence of floor space allowance on the growth of finishing pigs was used to develop prediction equations for ADG, ADFI, and G:F. Two databases were used: the first included information from studies examining the influence of floor space allowance, and the second included the aforementioned papers along with papers examining the impact of floor space after pigs were removed from the pen. The first database included 27, 25, and 25 papers for ADG, ADFI, and G:F, respectively, and the second database contained 30, 28, and 28 papers for ADG, ADFI, and G:F, respectively. The predictor variables tested were floor space (m2/pig), k (floor space/final BW0.67), initial BW, final BW, feed space (pigs per feeder hole), water space (pigs per waterer), group size (pigs per pen), gender, floor type, and study length (d). Floor space treatments within each experiment were the experimental unit and random effects of decade, paper within decade, and experiment within paper × decade interactions were included in the statistical model. A weighted variance term was included in the statistical model to account for heterogeneity of experimental designs and replication across the existing literature. The statistical significance for inclusion of terms in the model was determined at P < 0.10. Further evaluation of models with significant terms was then conducted based on the Bayesian information criterion (BIC). Once the ADG and ADFI models for each respective database were determined, then the G:F model was evaluated as the predicted ADG/predicted ADFI. The optimum equations to predict finishing ADG, ADFI, and G:F for the first database were ADG, g = 395.57 + (15,727 × k) ? (221,705 × k2) ? (3.6478 × initial BW, kg) + (2.209 × final BW, kg) + (67.6294 × k × initial BW, kg); ADFI, g = 802.07 + (20,121 × k) ? (301,210 × k2) ? (1.5985 × initial BW, kg) + (11.8907 × final BW, kg) + (159.79 × k × initial BW, kg); and G:F = predicted ADG/predicted ADFI. The optimum equations to predict ADG, ADFI, and G:F for the second database were ADG, g = 337.57 + (16,468 × k) ? (237,350 × k2) ? (3.1209 × initial BW, kg) + (2.569 × final BW, kg) + (71.6918 × k × initial BW, kg); ADFI, g = 833.41 + (24,785 × k) ? (388,998 × k2) ? (3.0027 × initial BW, kg) + (11.246 × final BW, kg) + (187.61 × k × initial BW, kg); and G:F = predicted ADG/predicted ADFI. All multiterm models improved BIC values compared with single-term predictor models, signifying that multiterm models proved to better fit their respective databases

Effects of diet form and type on growth performance, carcass yield, and iodine value of finishing pigs

Citation: Nemechek, J. E., Tokach, M. D., Dritz, S. S., Goodband, R. D., DeRouchey, J. M., & Woodworth, J. C. (2015). Effects of diet form and type on growth performance, carcass yield, and iodine value of finishing pigs. Journal of Animal Science, 93(9), 4486-4499. doi:10.2527/jas2015-9149Two experiments were conducted to determine the effects of pelleting, diet type (fat and fiber level), and withdrawal of dietary fiber and fat before marketing on growth performance, carcass yield, and carcass fat iodine value (IV) of finishing pigs. Each experiment used 288 pigs (initially 49.6 and 48.5 kg BW, respectively) with 6 dietary treatments arranged as 2 x 3 factorials. In Exp. 1, main effects were diet form (meal vs. pellet) and diet regimen. Diet regimens were 1) a low-fiber, low-fat (corn-soybean meal) diet from d 0 to 81, 2) a high-fiber, high-fat (30% dried distillers grains with solubles [DDGS] and 19% wheat middlings [midds]) diet from d 0 to 64 followed by the low-fiber, low-fat diet from d 64 to 81 (fiber and fat withdrawal), and 3) the high-fiber, high-fat diet fed from d 0 to 81. Pigs fed pelleted diets had increased (P < 0.05) ADG and G:F compared with those fed meal diets. Pigs fed pelleted diets had increased belly fat IV (2.9 mg/g) compared with those fed meal diets, with a greater increase when fed high-fiber, high-fat diets throughout the entire study (interaction, P < 0.05). Pigs fed the low-fiber, low-fat diet throughout had increased (P < 0.001) G:F compared with pigs fed the other 2 treatments. Pigs fed low-fiber, low-fat diets throughout the study or pigs withdrawn from high-fiber, high-fat diets had increased (P < 0.001) carcass yield compared with pigs fed high-fiber, high-fat diets throughout. In Exp. 2, treatment main effects were diet form (meal vs. pellet) and diet type (corn-soybean meal-based control, the control with 30% DDGS and 19% midds, or the control diet with 3% corn oil). The diet containing corn oil was calculated to produce carcass fat IV similar to diets containing DDGS and midds. Overall, pigs fed pelleted diets had increased (P < 0.05) ADG, G:F, and belly fat IV (1.3 mg/g) compared with those fed meal diets. Pigs fed the diets containing DDGS and midds had decreased (P < 0.05) ADG, carcass yield, and HCW compared with pigs fed the control or corn oil diets and decreased (P < 0.001) G:F compared with pigs fed added corn oil. Belly IV was greatest (P < 0.001) for pigs fed diets with DDGS and midds and lowest for pigs fed the control diet, with pigs fed the corn oil diets intermediate. In conclusion, pelleting diets improves pig ADG (approximately 3%) and G:F (approximately 6%); however, a novel finding of this study is that pelleting diets fed to finishing pigs also increases belly fat IV

Effect of fish meal source on nursery pig performance

Citation: Jones, A. M., Woodworth, J. C., Goodband, R. D., Tokach, M. D., Dritz, S. S., & DeRouchey, J. M. (2016). Effect of fish meal source on nursery pig performance. Journal of Animal Science, 94, 94-94. doi:10.2527/msasas2016-199A total of 350 pigs (DNA Line 200 × 400; initially 6.5 ± 0.09 kg BW; 21 d of age) were used in a 14-d experiment to determine the effects of fish meal source on nursery pig performance. Pigs were randomly allotted to pens at weaning (d 0) and were fed a common starter diet for 7 d. On d 7, pens of pigs were randomly allotted by BW to 1 of 7 dietary treatments (10 pens/treatment and 5 pigs/pen) in a 2 × 3 + 1 factorial. Diets were corn-soybean meal-based that contained 10% dried whey and none (Control) or 3 or 6% fish meal from 1 of 3 sources (IPC 790 Fish Meal, The Scoular Company, Minneapolis, MN; Special Select Menhaden Fish Meal, Omega Proteins, Houston, TX; and Daybrook LT Prime Menhaden Fish Meal, Daybrook Fisheries, Morristown, NJ). All fish meal sources were from the 2014 catch year. All samples of fish meal contained less than 0.15% total volatile N suggesting high quality. A source × level interaction (P < 0.05) for ADG and final BW was observed as increasing levels of IPC 790 improved ADG; however, pigs fed Special Select and LT Prime fish meal only saw improvement when 3% was included. While no differences were observed between treatments for ADFI, there was a source × level interaction for G:F (Linear P = 0.005). This was a result of G:F linearly improving as IPC 790 increased, with pigs fed 3% Special Select or LT Prime having similar performance to 6% IPC 790, but no further improvement thereafter. In conclusion, adding 3% of any fish meal source improved ADG and G:F; however, only pigs fed IPC 790 had a further improvement in ADG when 6% was fed

Evaluating the impact of maternal dietary vitamin D supplementation on sow performance, serum 25OHD3, and subsequent pig performance

Citation: Flohr, J. R., Bergstrom, J. R., Woodworth, J. C., Tokach, M. D., DeRouchey, J. M., Dritz, S. S., & Goodband, R. D. (2016). Evaluating the impact of maternal dietary vitamin D supplementation on sow performance, serum 25OHD3, and subsequent pig performance. Journal of Animal Science, 94, 125-125. doi:10.2527/msasas2016-265A total of 104 sows (PIC 1050; mean parity 2.2 ± 0.3) in 4 farrowing groups (25–27 sows per group) were used to determine the effects of gestational and lactational vitamin D supplementation on sow performance and serum 25OHD3. Sows were allotted to 1 of 4 dietary treatments (800, 2000, or 9600 IU of D3, or 50 µg of 25OHD3 [equivalent to 2000 IU/kg D3, DSM Nutritional Products Inc., Parsippany, NJ] per kg of diet) in a CRD. There were 25 to 27 sows per treatment. Maternal performance was not impacted by treatments. Increasing dietary D3 increased (linear, P = 0.001) sow serum 25OHD3. Sows fed 50 µg/kg of 25OHD3 had greater (P < 0.001) serum 25OHD3 than sows fed 800 or 2000 IU/kg, but decreased (P < 0.004) serum 25OHD3 compared to sows fed 9600 IU/kg. At weaning, increased maternal D3 increased piglet serum 25OHD3 (quadratic, P = 0.033), and pigs from sows fed 50 µg/kg of 25OHD3 had greater (P = 0.001) serum 25OHD3 compared to pigs from sows fed 800 IU/kg D3, but lower (P = 0.001) than pigs from sows fed 9600 IU/kg of D3. A subsample population of pigs (n = 448; PIC 327 × 1050; initially 6.6 ± 0.3 kg; 21 d of age) from 52 litters (2 of 4 farrowing groups) were used in a split-plot design (maternal treatment = whole plot; nursery treatment = subplot) to determine the influence of maternal and nursery dietary vitamin D on postweaning growth. Once weaned, pigs were allotted to pens based on maternal treatment, maintaining pre-weaning BW differences, and pens were randomly assigned to 2 nursery diets (2000 IU D3/kg or 50 µg 25OHD3/kg). There were 12 and 9 pens/treatment in nursery and finishing, respectively. Pen was the experimental unit. Growth performance was not influenced by nursery vitamin D. In the nursery, pigs from sows fed increasing D3 had increased (quadratic, P < 0.003) ADG and ADFI. Throughout finishing, ADG and G:F increased (quadratic, P < 0.05) with increasing maternal D3. Pigs from sows fed 50 µg/kg 25OHD3 had increased (P = 0.002) ADG compared to pigs from sows fed 800 IU/kg D3. Overall, increasing maternal D3 increased serum 25OHD3 concentrations, but more D3 (on an equivalent IU basis) is needed to achieve similar serum 25OHD3 responses compared to feeding 25OHD3. Pigs from sows fed 2000 IU/kg D3 grew faster after weaning compared to pigs from sows fed 800 or 9600 IU/kg D3 and pigs from sows fed 25OHD3 had greater ADG compared to pigs from sows fed 800 IU/kg D3

Evaluating the impact of maternal vitamin D supplementation: I. Sow performance, serum vitamin metabolites, and neonatal muscle characteristics

Citation: Flohr, J. R., Woodworth, J. C., Bergstrom, J. R., Tokach, M. D., Dritz, S. S., Goodband, R. D., & DeRouchey, J. M. (2016). Evaluating the impact of maternal vitamin D supplementation: I. Sow performance, serum vitamin metabolites, and neonatal muscle characteristics. Journal of Animal Science, 94(11), 4629-4642. doi:10.2527/jas2016-0409In Exp. 1, 56 gestating sows (PIC 1050; 35 d postinsemination) were used in a 30-d trial to determine serum 25(OH)D-3 response to increasing concentrations of dietary vitamin D3. Sows were randomly allotted to 1 of 7 dietary D3 treatments (200, 800, 1,600, 3,200, 6,400, 12,800, or 25,600 IU of added D3 per kilogram of complete diet) with 8 sows per treatment. Increasing D-3 increased (quadratic; P < 0.001) serum 25(OH)D-3 with the response depicted by the prediction equation: serum 25(OH) D3, ng/mL = 35.1746 + (0.002353 x dietary D-3, IU/d)- (0.0000000156 x dietary D3, IU/d(2)). In Exp. 2, 112 sows and their litters were used to determine the effects of dietary vitamin D regimen on sow performance, subsequent preweaning pig performance, neonatal bone and muscle characteristics, and serum vitamin metabolites. Sows were allotted to 1 of 4 dietary treatments 3 to 5 d following breeding: 800, 2,000, or 9,600 IU of D-3 per kilogram of the diet or 50 mu g of 25(OH) D-3 (2,000 IU of D-3 equivalent from Hy- D, DSM Nutritional Products, Parsippany, NJ) per kilogram of diet. There were 25 to 27 sows per treatment. Increasing dietary D-3 increased (linear, P = 0.001) serum 25(OH) D-3 of sows on d 100 of gestation, at farrowing, and at weaning. Increasing D-3 in sow diets increased piglet serum 25(OH)D-3 at birth (linear, P = 0.001) and weaning (quadratic, P = 0.033). Sows fed 50 mu g of 25(OH)D-3/kg had intermediate (P < 0.004) serum 25(OH)D-3 concentrations on d 100 of gestation, at farrowing, and at weaning compared with sows fed 2,000 IU of D-3/kg and sows fed 9,600 IU of D3/kg. Pigs from sows fed 50 mu g of 25(OH) D3/ kg had greater serum 25(OH)D-3 compared with pigs from sows fed 2,000 IU of D-3/kg, but at weaning, serum 25(OH)D-3 concentrations were similar. Also, pigs from sows fed 9,600 IU of D-3/kg had greater (P = 0.011) serum 25(OH) D3 at birth and weaning compared with pigs from sows fed 50 mu g of 25(OH) D-3/kg. Maternal performance, litter characteristics, neonatal bone ash content, and neonatal muscle fiber characteristics were largely unaffected by the dietary vitamin D treatments. Overall, D3 and 25(OH) D3 are both useful at increasing serum 25(OH)D-3 concentrations, but more D3 (on an equivalent IU basis) is needed to achieve similar serum 25(OH)D-3 responses compared with feeding 25(OH)D-3. Concentration of maternal vitamin D supplementation in lactation impacted milk transfer of the vitamin more so than the form of the vitamin, as evidence by the weaned pig serum 25(OH)D-3 concentrations

Stability of commercial phytase products under increasing thermal conditioning temperatures

Citation: De Jong, J. A., DeRouchey, J. M., Tokach, M. D., Goodband, R. D., Woodworth, J. C., Jones, C. K., . . . Bergstrom, J. R. (2016). Stability of commercial phytase products under increasing thermal conditioning temperatures. Journal of Animal Science, 94, 101-101. doi:10.2527/msasas2016-214The objective was to determine the stability of 4 commercial phytase products exposed to increasing thermal conditioning temperatures. The 4 commercial products used were: Quantum Blue 5G (AB Vista, Marlborough, United Kingdom); Ronozyme Hi Phos GT (DSM Nutritional Products, Parsippany, NJ); Axtra Phy TPT (Dupont, Wilmington, DE), and Microtech 5000 Plus (Guangdong VTR Bio-Tech Co., Ltd., Guangdong, China). The phytase products were mixed as part of a corn-soybean meal-based swine diet at a concentration recommended by the manufacturer to provide a 0.12% aP release. Diets were exposed to each of 4 thermal conditioning temperatures (65, 75, 85, and 95°C) for approximately 40 s and the entire process was repeated on 4 consecutive days to create 4 replicates. Samples were taken while feed exited the conditioner and before entering the pellet die. Phytase activity was determined from complete feed samples before conditioning to establish a baseline diet phytase activity level for each product. Phytase stability was measured as the residual phytase activity (% of initial) at each conditioning temperature. There were no product × temperature interactions for conditioning temperature, throughput, or residual phytase activity. As expected, as the target temperature was increased, conditioning temperature increased (linear, P < 0.001) and conditioner throughput decreased (linear, P < 0.001). As target temperature increased, phytase activity decreased (linear, P < 0.001) for each product. There was a significant phytase product main effect which was primarily caused by Microtech 5000 Plus having decreased (P < 0.05) phytase activity when compared to all other products at all conditioning temperatures. In summary, increasing conditioning temperatures decreased phytase stability regardless of product. In addition, Microtech 5000 Plus had decreased residual phytase activity (% of initial) when compared to all other products