No abstract

On-farm euthanasia of poultry is a necessity for minimizing disease spread and removing sick or injured birds to maintain optimum animal welfare. There are numerous methods that are approved for euthanasia of poultry by organizations like the American Veterinary Medical Association; however, all approved methods are not easily carried out on-farm or as effective as one another. Therefore, the objective of this study was to compare several captive bolt devices (Turkey Euthanasia Device, Zephyr-EXL, Jarvis Stunner, Experimental Crossbow), mechanical cervical dislocation (Broomstick method [ BRM ] and Koechner Euthanasia Device [ KED ]), and manual cervical dislocation ( MAN ) methods on 8 and 12-week-old turkey hens. Each method was assessed for impact on loss of brain stem reflexes, euthanasia success, and torn skin. The cervical dislocation techniques were also analyzed via radiograph for proper dislocation. Furthermore, each device was assessed for physical parameters. Turkeys (n = 1,400) were euthanized on 20 sampling days, 10 sampling days for each age period. All methods resulted in euthanasia of all turkeys in this study. The captive bolt devices all resulted in immediate loss of nictitating membrane and pupillary reflex at both the ages tested. The cervical dislocation methods differed in both nictitating membrane and pupillary reflex cessation at both ages ( P < 0.05). The pattern was the same at both ages with the KED device have longer latencies to cessation of both reflexes when compared to the BRM and MAN methods ( P < 0.05). Cessation of movement was also generally longer in dislocation methods compared to captive bolt at both ages. However, captive bolt devices resulted in more lacerations of the skin in general. MAN was also found to result in less damage to the vertebrae and proper location of separation than the mechanical methods of dislocation. All methods resulted in effective euthanasia; however, captive bolt methods resulted in immediate loss of brain stem reflexes indicating that they maybe more humane than cervical dislocation methods.

An experiment was conducted to evaluate the efficacy of a novel consensus bacterial 6-phytase variant expressed in Trichoderma reesei (PhyG) in broilers fed corn-soybean meal-based diets with application of dose-specific full nutrient and energy matrix values. Ross 708, straight-run broilers (n = 2,016) were assigned to one of 7 dietary treatments, with 12 replicate pens/diet and 24 birds/pen. Diets were a nutrient adequate control (PC), nutrient reduced negative controls 1, 2, and 3 (NC1, NC2, and NC3) with reductions in available phosphorus (avP) by 0.15%, 0.18%, and 0.19%, calcium (Ca) by 0.17%, 0.20%, and 0.21%, dig amino acids (AA) by 0.02-0.05%, sodium (Na) by 0.03-0.05%, and metabolizable energy (ME) by 62.8, 68.8, and 69.5 kcal/kg, respectively. Other diets were the NC1, NC2, and NC3 respectively supplemented with 500 (PhyG500), 1,000 (PhyG1000), and 2,000 (PhyG2000) FTU/kg. Over the 63-day feeding period, decreasing nutrient specifications lowered body weights (P&lt;0.05) in broilers from 4,518g in PC to 4,256 g and 4,191 g and increased body weight-corrected feed conversion ratio (FCR, P&lt;0.05) from 1.92 in PC to 2.06 and 2.08 in the NC2 and NC3, respectively. Compared with PC, PhyG maintained (P&gt;0.05) BW in broilers fed PhyG500 (4,474 g), PhyG1000 (4,417 g) and PhyG2000 (4,449 g). Moreover, PhyG at all dose-levels maintained (P&gt;0.05) overall FCR vs. PC. The NC1, NC2, and NC3 diets decreased (P&lt;0.05) tibia ash vs. PC, and eachPhyG500, PhyG1000, and PhyG2000 completely restored tibia ash to the similar levels (P&gt;0.05) as the PC. Carcass yield was decreased (P&lt;0.05) by NC1 (80.63%), NC2 (80.51%), and NC3 (80.31%) vs. PC (81.96%) with complete alleviation by PhyG500 (82.11%), PhyG1000 (81.80%), and PhyG2000 (81.54%). In conclusion, the novel consensus phytase variant completely compensated for the reduction in dietary avP, Ca, dig AA, and ME at each dose-level and maintained growth performance, bone quality, carcass characteristics, and nutrient digestibility in a typical corn-soybean mean based diet fed to broilers through 63 days of age.

No abstract

Background and Objective: Poultry diets are often formulated with corn-derived distillers dried grains and cereal grains. These grains contain higher levels of non-starch polysaccharides (NSPs) which are not digestible by broilers and can increase intestinal viscosity. $-glucan is partially water soluble which in turn causes a gel-like viscosity in the gastrointestinal tract of broilers. This reduces the diffusion rates of substrates and enzymes which leads to reduced nutrient absorption. The addition of glucanase enzymes has been shown to degrade plant cell walls releasing nutrients from grain endosperm while providing a probiotic effect. As a result, glucanases can improve broiler performance by allowing NSPs to be digested and absorbed. This experiment was conducted to evaluate the effects of different inclusion rates of corn-expressed glucanase (AC1) on apparent ileal digestibility (AID) and apparent metabolizable energy (AME). Materials and Methods: Broilers were fed a diet with corn-expressed glucanase enzyme (AC1) at different inclusion rates: Positive Control (PC, no enzyme balanced diet), Negative Control (NC, -100 kcal kgG 1 ME reduction from PC diet) and NC diets with corn-expressed glucanase added at different inclusion rates, with AC1 added at either 0.18 kg tG 1 , 0.35 kg tG 1 , 0.50 kg tG 1 , 0.75 kg tG 1 , or 2.00 kg tG 1 . At day 28 and 42, intestinal contents were collected from the ileum of 48 birds/trt. On d28, samples were analyzed for ileal digestibility and on day 42 samples were analyzed for AME and AME corrected for nitrogen. Results: Ileal digestibility was improved or equal to the PC and better than the NC in broilers fed AC1 at rates 0.35 kg tG 1 and higher for Ca and P digestibility (p<0.05). Both AME and AMEn were improved in broilers fed AC1 at rates of 0.35 kg tG 1 and higher when compared to the NC. The AMEn was equal in the PC and AC1 fed at 2.00 kg tG 1 . Conclusion: Feeding AC1 at rates greater than 0.35 kg tG 1 increases calcium and phosphorus digestibility and can return AME/AMEn to normal levels in diets with -100 kcal kgG 1 ME reductions. This could lead to improved feed efficiency and bone strength in broilers which could lead to improved performance and welfare.