161 research outputs found
Beak shape and nest material use in birds
This work was supported by a BBSRC Discovery Fellowship (grant no. BB/S01019X/1); the John Templeton Foundation (grant no. 60501); and the European Research Council (grant no. 788203).The evolution of behaviour can both influence, and be influenced by, morphology. Recent advances in methods and data availability have facilitated broad-scale investigations of physical form and behavioural function in many contexts, but the relationship between animal morphology and object manipulation-particularly objects used in construction-remains largely unknown. Here, we employ a new global database of nest materials used by 5924 species of birds together with phylogenetically informed random forest models to evaluate the link between beak shape and these nest-building materials. We find that beak morphology, together with species diet and access to materials, can predict nest-material use above chance and with high accuracy (68-97%). Much of this relationship, however, is driven by phylogenetic signal and sampling biases. We therefore conclude that while variation in nest material use is linked with that of beak shape across bird species, these correlations are modulated by the ecological context and evolutionary history of these species.Publisher PDFPeer reviewe
The Effects of Medium Chain Fatty Acids in Mash and Crumbled Pellet Diets on Growth Performance of Broilers
The objective of this experiment was to determine the effects of medium chain fatty acids (MCFA) in mash and crumbled pellet broiler diets. A total of 400 male chicks (Cobb 500; initial BW 0.092 lb) were housed in 4 Petersime batteries and used in an 18-d study. Treatments were randomly assigned to 80 cages within location block resulting in 8 cages per treatment with 5 chicks per cage at placement. Treatments were arranged in a 2 × 5 factorial with main effects of feed type (mash and crumbled pellet) and 0.5% MCFA inclusion (no inclusion, control; hexanoic acid, C6; octanoic acid, C8; decanoic acid, C10; and dodecanoic acid, C12). Fat inclusions in the diets were equalized using 0.5% soybean oil in the control diet. Prior to crumbling, diets were conditioned at 185°F for approximately 20 s and pelleted (CPM, model CL-5, Crawfordsville, IN) with a 5/32 × 7/8 in. ring die. Dietary treatments were fed for the full duration of the study. There was no evidence of feed form × MCFA interactions. From d 0 to 18, chicks fed pelleted diets had improved (P \u3c 0.001) body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR), and final BW compared to those fed mash diets. For the overall treatment period, there was no evidence of a MCFA effect (P \u3e 0.10) on broiler performance. Pelleting and crumbling feed improved growth performance regardless of MCFA inclusion. The MCFA inclusion did not positively influence growth performance of broilers
The Impact of Fines Inclusion Level and Conditioning Temperature on Pellet Quality and Energy Consumption
The advantages of pelleted feed can include improved handling, palatability, and nutrient availability. Poor pellet quality, however, can diminish these positive returns and lead to customer complaints. Thus, commercial feed mills may remove fines with a screener after cooling in order to provide a consistent product to customers. There are limited data on the effect of returning pellet fines back to the pellet mill on pellet quality and pellet mill efficiency. The objective of the following 2 experiments was to determine the effect of fines inclusion level and conditioning temperature on pellet quality and energy consumption. Experiment 1 treatments were arranged in a 3 × 2 factorial design of fines inclusion level (0, 10, and 20%) and conditioning temperature (170 and 180°F). Experiment 2 treatments were arranged in a 3 × 2 factorial design of fines inclusion level (0, 10, and 20%) and conditioning temperature (175 and 185°F). The results of Experiment 1 demonstrated there was no interaction between fines inclusion level and conditioning temperature on pellet durability index (PDI) (P \u3e 0.348). Increasing conditioning temperature from 170 to 180°F increased (P \u3c 0.003) PDI by 0.6 and 4.3% for both the standard and modified methods, respectively. There was a linear increase (P \u3c 0.032) in standard and modified PDI as the fines inclusion level increased. The results of Experiment 2 demonstrated that there was an interaction between fines inclusion level and conditioning temperature for modified PDI (P \u3c 0.001). When the diets were pelleted at 185°F, increasing the fines inclusion level increased the modified PDI. However, there was no significant difference for modified PDI of the diets with 0, 10, and 20% fines inclusion level when they were pelleted at 175°F. For starch analysis, there was no interaction between fines inclusion level and conditioning temperature on total starch. There was no evidence of difference in total starch between the diets that were pelleted at 175 and 185°F. The total starch was the lowest in the diet with 0% fines (54.11%) followed by the diet with 20% and 10% fines (56.42% and 57.90%), respectively (P = 0.013). For gelatinized starch and cooked starch, there was no interaction between the fines inclusion level and conditioning temperature. Both fines inclusion level and conditioning temperature did not affect gelatinized starch. For energy consumption, there was an interaction (P \u3c 0.0001) between fines inclusion level and conditioning temperature. When the diets were pelleted at 185°F conditioning temperature, the diet with 20% fines required significantly more energy during the pelleting process as compared to the diets with 0 and 10%. However, there was no significant difference in energy consumption for diets containing 0, 10, and 20% fines when the diets were pelleted at 175°F conditioning temperature. Therefore, increasing conditioning temperature increased pellet quality. When a diet contained less than 1.5% oil, recirculating fines through the conditioner and pellet die improved pellet quality. However, the 20% inclusion of fines led to occasional roll slips, decreased pellet mill stability, and increased energy usage when the diet was pelleted
Effects of Dry and Liquid Pellet Binder Inclusion and Conditioning Temperature on Pellet Mill Efficiency and Pellet Quality of a High-Fiber Ruminant Ration
The objectives of this experiment were: 1) to determine the effects of sucrose and lactose-based liquid ingredient inclusion on the pelleting efficiency and quality of a high-fiber diet; and 2) to evaluate the role of mash conditioning temperature on the binding effectiveness of the tested liquid ingredients. Binders included DLS (dry calcium lignosulfonate), LCM (liquid cane molasses), LMB (commercial liquid molasses blend), and LLB (commercial liquid lactose blend). Treatments were arranged in a 5 × 3 factorial of pellet binder (control, DLS, LCM, LMB, and LLB) and conditioning temperature (165, 175, and 185°F). Data were analyzed using the GLIMMIX procedure of SAS with linear and quadratic contrasts for increasing conditioning temperature. Treatments were arranged in a completely randomized design and replicated 3 times. Diets were conditioned for approximately 40 s and pelleted with a 0.19 × 1.75 in. die at a rate of 3.0 ton/h. Pellet durability index (PDI) was determined using the standard and modified tumble box methods. There was no evidence of an interaction (P \u3e 0.209) between binder type and conditioning temperature when determining PDI according to either the standard or modified tumble box methods. Conditioning temperature alone did not affect PDI (P \u3e 0.119); however, differences were observed based on binder inclusion according to either method (P \u3c 0.046). Using the standard method of analysis, PDI was improved (P \u3c 0.046) by LCM and LLS addition compared to both the control and LCM diets, while LLB was intermediate. According to the modified method with greater agitative stress, PDI was improved (P \u3c 0.005) when using LCM and LLB compared to the control diet, with DLS and LCM being intermediate. Additionally, LCM inclusion reduced (P \u3c 0.001) pellet mill throughput and increased (P \u3c 0.001) energy consumption of the pellet mill motor compared to the control and other binders, with no observed differences (P \u3c 0.269) resulting from increased conditioning temperature. Under the constraints of this trial, cane molasses and commercial molasses and lactose blends were shown to be effective pellet binders, regardless of conditioning temperature when included in a high-fiber ration. However, challenges with molasses handling characteristics and increased friction at the die interface may reduce its practical application and encourage the use of the alternative commercial blends
Crystal size, shape, and conformational changes drive both the disappearance and reappearance of ritonavir polymorphs in the mill.
Organic compounds can crystallize in different forms known as polymorphs. Discovery and control of polymorphism is crucial to the pharmaceutical industry since different polymorphs can have significantly different physical properties which impacts their utilization in drug delivery. Certain polymorphs have been reported to 'disappear' from the physical world, irreversibly converting to new ones. These unwanted polymorph conversions, initially prevented by slow nucleation kinetics, are eventually observed driven by significant gains in thermodynamic stabilities. The most infamous of these cases is that of the HIV drug ritonavir (RVR): Once its reluctant form was unwillingly nucleated for the first time, its desired form could no longer be produced with the same manufacturing process. Here we show that RVR's extraordinary disappearing polymorph as well as its reluctant form can be consistently produced by ball-milling under different environmental conditions. We demonstrate that the significant difference in stability between its polymorphs can be changed and reversed in the mill-a process we show is driven by crystal size as well as crystal shape and conformational effects. We also show that those effects can be controlled through careful design of milling conditions since they dictate the kinetics of crystal breakage, dissolution, and growth processes that eventually lead to steady-state crystal sizes and shapes in the mill. This work highlights the huge potential of mechanochemistry in polymorph discovery of forms initially difficult to nucleate, recovery of disappearing polymorphs, and polymorph control of complex flexible drug compounds such as RVR
Effects of Conditioning Temperature and Pellet Mill Die Speed on Pellet Quality and Relative Stabilities of Phytase and Xylanase
The objective of this experiment was to determine the effect of conditioning temperature and die speed on pellet quality and enzyme stability of phytase and xylanase. Treatments were initially arranged as a 2 × 3 factorial of conditioning temperature (165 and 185°F) and die speed (127, 190, and 254 rpm); however, when conditioning at 185°F it was not possible to pellet at 127 rpm. Thus, data were analyzed in 2 different segments using the GLIMMIX procedure of SAS. First, linear and quadratic contrasts were utilized to test the response to increasing die speed at 165°F. Second, the data were analyzed as a 2 × 2 factorial of conditioning temperature (165 and 185°F) and die speed (190 and 254 rpm). Treatments were arranged in a completely randomized design and replicated 3 times. Diets were conditioned for approximately 30 s and pelleted with a 3/16 in. diameter × 1 3/4 in. effective length die at a rate of 5 ton/h. Pellet durability index (PDI) was determined using the tumble box and Holmen NHP 100 methods. Samples of the unconditioned mash (M), conditioned mash (CM), and pellets (P) were collected and analyzed for phytase and xylanase concentration. Relative enzyme stabilities were expressed as CM:M and P:M. Stabilities expressed as P:M were used an indication of enzyme stability through the entire pelleting process. Diets conditioned at 165°F showed no evidence of difference in phytase or xylanase P:M stability when decreasing die speed from 254 to 127 rpm. However, when conditioning diets at 165°F, decreasing die speed increased (linear, P \u3c 0.001) PDI. There was no conditioning temperature × die speed interaction for overall xylanase P:M stability or PDI. However, there was a conditioning temperature × die speed interaction (P \u3c 0.01) for phytase P:M stability. When conditioning diets at 185°F, increasing die speed decreased phytase P:M stability. However, when conditioning at 165°F, increasing die speed did not influence phytase P:M stability. For main effects of conditioning temperature, increasing temperature improved (P \u3c 0.001) PDI with no evidence of difference for xylanase P:M stability. For the main effects of die speed (254 vs. 190 rpm), decreasing die speed decreased (P \u3c 0.001) the P:M xylanase stability, but there was no evidence of difference for PDI. The results of this trial indicate that die speed should be taken into consideration when evaluating enzyme stability of both phytase and xylanase as pellet mill models may be operating at different speeds. Additionally, increasing conditioning temperature will improve PDI, but may result in decreased phytase stability
Effect of Feed Form, Corn Particle Size, and Extrusion of Corn on Broiler Performance
The pelleting and extrusion processes use both thermal and mechanical energies to alter the crystalline structure of the starch granule, which makes it more digestible than raw starch. The particle size of the ground corn particle in the diet also affects the rate at which gelatinization occurs in the extrusion process. There is limited research on broiler performance when feeding diets that contain different particle sizes of corn prior to extrusion. The objective of this study was to determine the effect of feed form, corn particle size and the extrusion of corn on growth performance of 21-d-old broiler chicks. To determine the effect of corn type on growth performance, treatments were arranged in a 2 × 3 factorial of corn type (raw corn and extruded corn) and corn particle size (400, 800, and 1200 μm). There was no interaction (P \u3e 0.742) between corn type and corn particle size on d 21 BW, ADFI, or feed conversion ratio (FCR). Broilers fed the raw corn diet had greater (P \u3c 0.001) d 21 BW and ADFI compared to those fed the extruded corn diets. There was no evidence of difference (P \u3e 0.081) in d 21 BW and ADFI in broilers fed the three different corn particle sizes. Broilers fed diets with increasing corn particle size had increased (linear, P = 0.015) FCR. There was an interaction (P \u3c 0.039) between corn type and corn particle size on both the relative gizzard and pancreas weights of broilers. To determine the effects of feed form on growth performance and relative gizzard and pancreas weight, treatments were arranged in a 2 × 2 factorial of feed form (mash and crumble feed) and corn particle size (400 and 800 μm). There was no evidence of interaction (P \u3e 0.180) between feed form and corn particle size on growth performance or relative gizzard and pancreas weight. Broilers fed the crumble extruded corn diet had increased (P = 0.001) d 21 BW and ADFI compared to those fed the mash extruded corn diets. There was no evidence of difference (P \u3e 0.189) in d 21 BW, ADFI, and FCR between broilers fed extruded diets containing 400 μm corn and 800 μm corn regardless of feed form. Broilers fed the mash extruded corn diet had greater (P \u3c 0.001) relative gizzard and pancreas weights as compared to those fed the crumbled extruded corn diets. In addition, broiler relative gizzard weight was greater (P = 0.002) for those fed the extruded corn diet containing 800 μm versus 400 μm corn, while there was no evidence of difference in relative pancreas weight. Therefore, increasing the amount of gelatinized starch in the feed by replacing ground corn with extruded corn in a broiler starter diet did not improve growth performance. Increasing corn particle size led to improved gizzard development
The Effect of Different Inclusion Levels of Corn Starch and Fine Ground Corn With Different Conditioning Temperature or Die Thickness on Pellet Quality
Feeding a greater percentage of whole pellets to poultry and swine provides a greater return on investment for producers. Pellet binders are commonly used in commercial feed mills, but the added cost has limited their use in poultry and swine feed mills. Corn starch could be a potential natural binder for feed as it is for biomass pellet operations. Therefore, the objective of these experiments was to determine the effect of different inclusion levels of corn starch and fine ground corn with different conditioning temperature or die thickness on pellet quality. In, Experiment 1, treatments were arranged in 3 × 2 factorial design of corn starch inclusion level (0%, 5%, and 10%) and die thickness (1/2 in. and 7/8 in.). In Experiment 2, treatments were arranged in 3 × 2 factorial design of fine ground corn inclusion level (0%, 10%, and 20%) and conditioning temperature (175 and 185°F). For Exp. 1, there was a corn starch by die thickness interaction (P = 0.033; Table 3) on pellet durability index (PDI). Increasing concentration of corn starch from 0 to 10% in the diet decreased PDI when diets were pelleted using the ½ in. thick die. However, there was no evidence of difference in PDI when corn starch was increased from 0 to 10% and diets were pelleted using the 7/8 in. die. There was no evidence of an interaction between corn starch inclusion level and die thickness on modified PDI. Increasing die thickness from 1/2 in. to 7/8 in. increased (P = 0.001) modified PDI. There was a linear decrease (P \u3c 0.001) in modified PDI as the corn starch inclusion level increased. For Exp. 2, there was no evidence for interaction between fine ground corn inclusion level and conditioning temperature on PDI (P \u3e 0.541). There was no evidence of difference in PDI with increasing fine ground corn inclusion. Increasing conditioning temperature from 175 to 185°F increased (P \u3c 0.0001) standard and modified PDI. In conclusion, the use of pure corn starch was not an effective binding agent in the feed when the diet contained at least 60% ground corn. The ratio of small corn particles to large corn particles in the diet did not impact pellet quality when the diets were conditioned above 175°F for 35 s and then pelleted with a 5.6 L:D die. Increasing die thickness and conditioning temperature improved pellet quality
The Influence of Ingredients, Corn Particle Size, and Sample Preparation on the Predictability of the Near Infrared Reflectance Spectroscopy
The near infrared reflectance spectroscopy (NIRS) technique is a rapid and non-destructive technique used to evaluate the chemical composition of complete feed and ingredients. The accuracy of its prediction relies upon calibration standards to account for variations in material composition and particle shape and size. The purpose of this study was to determine the effect of alternative ingredient inclusion and corn particle size along with sample preparation method on the accuracy of the NIRS technique using standard calibrations provided with the instrument. Treatments were arranged as a 4 × 3 × 3 factorial with diet type (soybean meal (SBM) + DDGS (SD); SBM + fish meal + DDGS (SFD); SBM + fish meal + wheat bran (SFB); and SBM + wheat bran (SB)); corn particle size (400, 600, and 800 μm); and method of analysis (laboratory, NIRS-ground, and NIRS-unground). All samples were evaluated for crude protein (CP) content. Laboratory values from wet chemistry analyses were obtained using the Dumas Combustion method for comparison to results from the NIRS. Ground and unground samples for NIRS were scanned on a Foss NIRS D2500 machine with a wavelength range of 400 to 2,500 nm at a reflectance of log (1/R) at 2 nm intervals for each sample. There was no diet × particle size × method interaction on CP; however, there was an interaction (P ≤ 0.05) between diet and method of analysis. When analyzing diets using laboratory methods there were no differences in CP, but when using the NIRS, grinding samples prior to NIRS analysis improved the results compared to not grinding, though they were still lower than laboratory analysis. There was also an interaction (P ≤ 0.05) between corn particle size and method of analysis. The CP content of NIRS-ground and laboratory samples were similar within the methods used, and values obtained for the different particle sizes were closer to the expected CP (20%) as compared to the NIRS-unground samples. Results from NIRS-unground samples of diets were significantly different and lower than results from laboratory analysis. However, results from the NIRS-ground samples were intermediate between NIRS-unground and laboratory analysis. Results of this trial indicate the necessity for proper calibration biasing to improve the prediction accuracy of NIRS, especially when diets contain alternative ingredients. Grinding the sample prior to scanning with the NIRS will improve accuracy, though values may still differ from laboratory methods when using standard equipment calibrations, further emphasizing the importance of calibration biasing
Determining the Amino Acid Digestibility of Soybean Meal from Different Midwest Soybean Varieties Fed to Broilers
At hatch, 240 one-day old Cobb500 male broilers were placed in battery cages to determine soybean meal (SBM) apparent ileal digestibility (AID) of amino acids (AA). There were 6 broilers per cage and 10 replicates per treatment. A common corn-SBM crumble starter diet was fed from d 0 to 10 with experimental mash diets fed from d 10 to 18 with SBM as the only source of AA. Dietary treatments consisted of 1 of 4 soybean sources varying in quality determined by crude protein (CP) content and processed into SBM. Dietary treatments consisted of a commercially processed SBM with 47% CP (CSBM) or experimentally processed SBM with 42% CP (42SBM), 49% (49SBM), or 52% CP (52SBM). Two sources consisted of soybeans from a similar region and were processed either commercially (CSBM) or experimentally (49SBM) solvent extracted at Texas A&M University. Additional sources included a low quality (42SBM) and highquality (52SBM) soybean, experimentally solvent extracted into SBM at a pilot-scale facility at Texas A&M University. Dietary treatments were dextrose and SBM-based, and consisted of 1 of 4 SBM sources included in diets formulated to 20% CP. On d 18, broilers were euthanized by CO2 inhalation and ileal samples were collected for determination of AID of AA. Soybean meal processed from low, medium, and high CP soybeans resulted in increased concentrations of crude protein and indispensable AA. Individual SBM samples indicated that SBM with higher CP had lower NDF. Data were analyzed using the GLIMMIX procedure in SAS 9.4, with cage as the experimental unit, cage location as the blocking factor with Tukey-Kramer adjustment for multiple comparisons used. For soybeans grown in a similar region, broilers fed CSBM, processed conventionally, had increased (P \u3c 0.05) AID of total AA, Arg, His, Lys, and Thr compared to 49SBM, processed experimentally. Increasing the CP content of SBM from 42SBM, and 49SBM, to 52SBM increased (P \u3c 0.05) AID of total AA, Arg, His, Leu, Lys, Thr, and Val. Broilers fed CSBM, 49SBM, and 52SBM had increased (P \u3c 0.001) Ile, Met, Phe, and Trp compared to broilers fed 42SBM. In conclusion, CSBM and 49SBM were sourced from a similar location but processed either commercially or experimentally, respectively. Commercially processed SBM had improved AID AA compared to the experimentally processed SBM. Additionally, SBM with increasing concentrations of CP and AA had improved AID of AA
- …