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An experiment was conducted to investigate the effects of using gelatin as a partial protein source and protease in broilers diets. The experiment was carried out as a factorial arrangement, containing two levels of protease (0 and 200 gs per ton of diet) and four levels of gelatin (0, 2.82, 4.23 and 5.64% of the diet replacing 12.5, 18.75 and 25% of the SBM protein, respectively) with 6 replicates and 15 chicks in each pen. Body weight, feed intake and FCR were measured at day 7, 21 and 35. Ileal digesta viscosity, ileal morphology and ileal coliform and lactobacilli population were measured at day 35. In addition, apparent protein digestibility was determined between 28 and 35 days of age. Results show that the highest inclusion rate of gelatin decreased body weight and feed intake (P

Exogenous protease has formed part of several commercial enzyme admixtures for the past 15–20 years but has become available as a mono-component enzyme only in the last 5–10 years (Cowieson and Adeola, 2005; Fru-Nji et al., 2011). As part of an enzyme admixture (often also containing various carbohydrases and/or phytase) it is difficult to separate the contributions of the component parts and the efficacy of each has implicit rather than explicit value. However, the effectiveness of mono-component enzymes can be readily assessed under different production and nutritional circumstances and their complementarity with alternative enzymes is readily rendered transparent. The motivation for the use of exogenous protease in non-ruminant nutrition is typically the reduction of feed cost at constant animal performance. This objective is usually achieved via displacement of expensive protein/amino acid sources in the diet through the assignment of a nutrient matrix on the enzyme in least cost formulation. Recently attention has moved from this classical approach to protease application to so-called ‘extra-proteinaceous’ effects including environmental benefits, litter management, enteric resilience, uniformity and microbial stability. Whilst these ‘secondary’ effects may not be the principal motivator for the use of proteases in animal production they are increasingly visible and require explanation. Furthermore, these responses, if understood, allow positive translation to production metrics such as reduced FCR and improved weight gain. It is the purpose of this review to briefly summarise the current state of the art in mono-component exogenous protease use in non-ruminants and to suggest mechanisms whereby the ‘extra-proteinaceous’ effects may be explained. Finally, key diet/animal factors that may promote beneficial effects of exogenous protease on live performance will be discussed.

Three experiments were conducted to quantify the efficacy of exogenous protease in poultry diets containing soybeans with varying trypsin inhibitor (TI) concentrations. Test diets contained 4 g/kg of TiO2 as a digestibility marker and protease (CIBENZA® DP100 at 300 U/g diet, Novus International). A randomized complete block design was analyzed using ANOVA with LSD multiple pair-wise comparison used to compare treatment means. For Exp 2 and 3, a common starter diet was fed to broiler chickens until d 16 of life and then switched to test diets. Exp 1 was a 2×6 factorial arrangement of 2 protease levels (0 and 300 U/g) and 6 dietary TI levels (0.72, 1.16, 1.61, 2.06, 2.50, and 2.95 mg/g) with 6 replicates/treatment; 8 chicks/pen. In Exp 2 (12 replicates/treatment; 8 chicks/pen), apparent ileal AA digestibility (AIAAD) was evaluated in diets containing 250 g/kg full fat extruded soybeans (FFES)+SBM (negative control; 5.8 mg/g TI) with or without protease or SBM (positive control; 3.1 mg/g TI). Test diets were fed from d 16–21 of age, AIAAD and relative pancreas weight was measured on d 21. In Exp. 3, broilers were allocated to a 2×2 factorial arrangement of treatments with 9 replicates/treatment and 8 chicks/pen. The dietary factors were SBM inclusion (420 or 960 g/kg; SBM TI = 3.85 mg/g), or protease inclusion (0 or 300 U/g). Test diets were fed from d 22–30, ileal digesta was collected on d 30. With increasing TI, pancreas weight increased (P

A meta-analysis was conducted to investigate the effect of mono-component proteases on performance and apparent ileal amino acid digestibility (AIAAD, %) in monogastrics. A total of 67 experimental trials were included in the meta-analysis from published and internal reports, contributing 467 lines of data. Poultry and swine data accounted for 81 and 19% of the dataset, respectively. Forty-four different proteases were included in the meta-analysis, accounting for commercial and non-commercial products. Mixed Model analysis was used to assess protease effect and the influence of inherent characteristics of the control on protease response. The mean performance response to protease was a reduction in feed conversion ratio (FCR) for poultry (1%, P0.05) and swine (4%, P0.05). The mean relative effect of protease on AIAAD over the control was 1.6 ± 0.3%, ranging from 1.2% for Arg, Phe and Trp to 2.6% for Cys. For the majority of amino acids, inherent AIAAD of control diets influenced (P0.05) the magnitude of the protease response such that, as inherent digestibility increased, the effect of protease on amino acid digestibility decreased. The dataset was subsequently divided into 2 subgroups: diets with and without other enzymes, namely non-starch polysaccharide degrading enzymes (NSPase) and phytase. Addition of protease in diets containing no other enzymes significantly (P0.05) increased AIAAD for the majority of amino acids and tended (P0.10) to improve Met, Trp, Pro, Gly, and Tyr. However, when other enzymes were included in the experiment, the beneficial effect of protease on AIAAD was lost (P0.05). These findings suggest that when other enzymes are already included in the diet, addition of protease requires further justification for use in monogastric diets.

SUMMARY Two experiments were conducted to determine the effect of adding an exogenous protease to corn-, soybean meal-, and meat and bone meal-based broiler diets. In the first experiment, 1,764 male Ross 308 broiler chicks were placed in 63 floor pens, with 28 birds per pen. There were 7 treatments, with 9 replicates each, fed in the starter (d 1 to 21) and grower (d 22 to 40) phases. The dietary treatments were a positive control, formulated with 3,050 and 3,150 kcal of ME/ kg and 22.5 and 20% CP in the starter and grower phases, respectively, and a negative control, formulated with a 4.4% reduction in ME and CP as compared with the positive control diets. A mono-component protease (75,000 protease/g) was added to the negative control diets at 0, 100, 200, 400, 800, and 1,600 ppm of feed. Broilers fed the positive control diet grew better and had a better feed-to-gain ratio (FE) than did those fed the negative control diets, regardless of enzyme supplementation. Protease supplementation had no effect on BW; however, FE was improved in a quadratic manner as protease was increased. In experiment 2, a factorial arrangement of 2 protein (7% difference in CP), 2 energy (3% difference in ME), and 2 protease (0 and 200 ppm) concentrations was used, resulting in 8 treatments replicated 11 times (22 male Cobb 500 broilers per replicate). No 3-way interactions were observed for live performance measures. Broilers fed the high-protein and high-energy diets performed better (P ≤ 0.01) than those fed the low-protein and low-energy diets. Protease supplementation improved FE as well as digestibilities of fat and CP (P ≤ 0.01), regardless of dietary protein or energy concentration. The protease used in these studies improved FE and dietary determined AME values as well as dietary CP and fat digestibility values.

Summary. MonoFIX-VF, a monocomponent factor IX concentrate, has replaced the use of Prothrombinex-HT as the treatment of choice for patients with factor IX deficiency in Australia. The haemostatic effect of MonoFIX-VF, administered by continuous infusion, was assessed in four subjects being treated for 10 bleeding episodes including five surgical procedures. MonoFIX-VF was found to be a safe and effective treatment for patients with haemophilia B.

SummaryA meta-analysis of the effect of a mono-component bacterial protease (RONOZYME® ProAct) on the apparent ileal digestibility of amino acids in poultry and swine diets was conducted to examine functional patterns, mean effects and variability of response. A total of 25 independently-conducted experiments were included comprising a total of 804 datapoints. The mean response to protease was +3.74% (SE 1.1%, P 0.05). However, the inherent digestibility of amino acids in the control diet as a single explanatory term explained around 47% of the variance (P

Lettre a l'editeur: l'insuline, per se, n'est pas antigenique mais c'est la pro-insuline contenue dans les preparations d'insuline non monocomposee qui pre-sensibilise les lymphocytes de ces patients diabetiques