Chitinolytic Activity of Mucosal Enzymes in the Different Parts of the Digestive Tract in Broilers

The present study was performed to measure activities of mucosal chitinase and N-acetyl-beta-D-glucosaminidase (NAGase) in the proventriculus, duodenum jejunum and ileum of broilers given standard and shrimp meal (SM) diets. Activities of both enzymes were extremely high (P<0.05) in the proventriculus, and low or negligible in other parts, and in the proventriculus, activity of chitinase was much greater than that of NAGase. Dietary SM containing chitin had little or decreasing effect on activities of both enzymes. The result obtained here suggests that in broilers, chitin digestion by mucosal enzymes occurs mainly in the proventriculus, and the enzyme activities are not stimulated by dietary chitin.ArticleJOURNAL OF POULTRY SCIENCE. 50(1):65-67 (2013)journal articl

Targeting hypoxic response for cancer therapy

Hypoxic tumor microenvironment (HTM) is considered to promote metabolic changes, oncogene activation, and epithelial mesenchymal transition, and resistance to chemo- and radio-therapy, all of which are hallmarks of aggressive tumor behavior. Cancer cells within the HTM acquire phenotypic properties that allow them to overcome the lack of energy and nutrients supply within this niche. These phenotypic properties include activation of genes regulating glycolysis, glucose transport, acidosis regulators, angiogenesis, all of which are orchestrated through the activation of the transcription factor, HIF1A, which is an independent marker of poor prognosis. Moreover, during the adaptation to a HTM cancer cells undergo deep changes in mitochondrial functions such as “Warburg effect” and the “reverse Warburg effect”. This review aims to provide an overview of the characteristics of the HTM, with particular focus on novel therapeutic strategies currently in clinical trials, targeting the adaptive response to hypoxia of cancer cells

Improvement in the in vitro Digestibility of Shrimp Meal by the Addition of Persimmon Peel

The present study was conducted to analyze the chemical properties of persimmon peel (PP) and the in vitro digestibility of shrimp meal (SM) diets containing PP. Discussions whether PP can be used as a feed additive to promote digestion of SM in chickens are also included. The chemical composition and chitinase activity of dried PP was studied. SM diets containing PP were formulated according to the 4 by 6 factorial design: 4 levels of SM (0%, 10%, 15%, and 20%) × 6 levels of PP (0%, 2%, 4%, 6%, 8%, and 10%). The in vitro digestibility of dry matter (IVDMD), crude protein (IVCPD), and chitin (IVCD) was also studied. PP was rich in nitrogen-free extract (NFE, about 74%) and tannin (2.8%), and the highest chitinase activity of PP was observed at pH 4.5. Approximately 50% of chitinase activity was also observed at acidic (3.0) and alkaline (8.0) pH. Its activity was slightly affected by pepsin treatment. IVDMD increased upon addition of up to 8% PP, but decreased with an increase in the level of SM. When PP level was increased up to 6%, IVCPD in the group containing 0% SM, changed slightly; however, an increasing trend was observed in the other groups. When PP level was more than 6%, IVCPD decreased in all the groups. IVCD increased dose-dependently with increasing level of PP and decreased with increasing level of SM. In conclusion, PP was rich in NFE, had high chitinase activity, and improved all digestibility parameters, such as IVDMD, IVCPD, and IVCD, in SM diets where the PP level was under 6%. Thus, up to 6% of PP can be safely included in SM diets as a digestion promoter

Effect of Shrimp Meal Made of Heads of Black Tiger (Penaeus monodon) and White Leg (Litopenaeus vannamei) Shrimps on Growth Performance in Broilers

The present study was conducted to measure the growth performance in growing broilers given shrimp meal (SM) made of heads of black tiger (Penaeus monodon) (BT) and white leg (Litopenaeus vannamei) (WL) shrimps. Forty-two male broiler chicks (8 days old, Ross 308) were randomly divided into 7 dietary groups (control, 5% BT, 10% BT, 15% BT, 5% WL, 10% WL and 15% WL) having similar body weight (6 birds per diet). Metabolisable energy and CP were adjusted to about 3,180 kcal/kg and about 235 g/kg, respectively, and other nutrients were formulated to meet or slightly exceed the requirements. Diet and water were provided ad libitum during the experimental period (8 to 21 days old). The results revealed that body weight gain decreased in BT groups with increasing level of SM (P&lt;0.05), and feed intake decreased slightly with increasing level of SM in diets. As the result, feed conversion ratio also deteriorated with increasing level of SM. Similar trend was observed in WL groups, but the adverse effects of SM were milder comparing with BT groups. Nitrogen retention in both BT and WL groups tended to decrease with increasing level of SM. Chitin digestibilities in WL groups were greater than the corresponding values in BT groups. In conclusion, it is suggested that WL heads can be more nutritious SM for broiler diets than BT heads

Phytase Activity in the Digesta from Different Parts of the Digestive Tract and Ileal Digestibility of Nutrients in Broilers Fed with Buckwheat Diets

In the present study, the effects of dietary buckwheat on phytase activity in the digesta from different parts of the digestive tract, and ileal digestibility of nutrients were determined in broilers fed with buckwheat diets. Eighty male broilers (29-d-old) were divided into four groups (20 birds each), and were fed one of the following diets until they were 36-d-old: positive control (PC) diet formulated based on the NRC recommendations, negative control (NC) diet containing 0.15% lower non-phytate phosphorus (P) than that in the PC diet, and two other diets formulated by replacing corn in NC diet with either 20% non-germinated (BU) or germinated (GBU) buckwheat. At the age of 36 d, broilers were sacrificed to collect digesta from the crop, gizzard, duodenum, jejunum, ileum, and cecum. The activity of phytase was low in the PC and NC diets, which increased in the BU diet and increased further in the GBU diet. A similar trend was observed in the crop digesta; however, the phytase activity in the crop digesta of BU and GBU diets was marginally lower when compared with that in each diet. These values decreased sharply when the digesta moved to the gizzard, and then decreased gradually. The ileal digesta exhibited significantly low activity with negligible effect of dietary treatment. The result of two-way analysis of variance with germination and digestive tract parts as main factors showed that the effect of digestive tract parts and interaction between factors was significant on the phytase activity in digesta. The dietary BU and GBU did not affect the ileal crude protein digestibility; however, it increased the ileal phytate P digestibility. These results suggest that in broilers, the crop might be the primary site of phytate degradation by buckwheat phytase, and the buckwheat might have negligible adverse effect on ileal digestibility of nutrients

Chitinolytic Activity of Mucosal Enzymes in the Different Parts of the Digestive Tract in Broilers

The present study was performed to measure activities of mucosal chitinase and N-acetyl-beta-D-glucosaminidase (NAGase) in the proventriculus, duodenum jejunum and ileum of broilers given standard and shrimp meal (SM) diets. Activities of both enzymes were extremely high (P<0.05) in the proventriculus, and low or negligible in other parts, and in the proventriculus, activity of chitinase was much greater than that of NAGase. Dietary SM containing chitin had little or decreasing effect on activities of both enzymes. The result obtained here suggests that in broilers, chitin digestion by mucosal enzymes occurs mainly in the proventriculus, and the enzyme activities are not stimulated by dietary chitin.ArticleJOURNAL OF POULTRY SCIENCE. 50(1):65-67 (2013)journal articl

Phosphorus Availability in Laying Hens Given Non-phytate Phosphorus Deficient Diets Containing Buckwheat

To date, the effect of buckwheat phytase on laying hens has not yet been investigated. Thus, this study was conducted to compare the production performance, egg quality, and phosphorus (P) balance of laying hens given nonphytate P deficient diets supplemented with non-germinated buckwheat (BU) or germinated buckwheat (GBU). Experimental diets (17.8% CP, 2,988 kcal/kg ME) consisted of two control diets, the positive control (PC), satisfying all nutrient requirements and negative control (NC) containing 0.16% less non-phytate P than that in the PC diet, and six experimental diets (containing 10%, 15%, 20% BU or GBU), prepared by replacing maize with BU or GBU, along with the raw materials of NC diet. Fifty-six laying hens (46 week of age) were allocated to eight dietary groups (seven hens each) and experimental diets were given for a period of six weeks (week one was employed for acclimatization, and the subsequent five weeks for data collection). Deteriorated production performance (hen-day egg production, feed intake, egg weight and egg mass) and eggshell quality (shell breaking strength, shell weight and shell thickness) in laying hens given a non-phytate P deficient NC diet was restored by the addition of at least 15% BU and 10% GBU to the NC diet. Total P retention significantly increased in 20% BU, 15% GBU and 20% GBU groups as excretion decreased considerably in these groups than the NC group. Considering the hen-day egg production as an economically important parameter, we found that a 340 phytase unit (PU)/kg diet of buckwheat phytase was equivalent to 0.10% non-phytate P in laying hens. These results suggested that the addition of buckwheat in non-phytate P deficient diets can alleviate the deficiency and improve P availability in laying hens

Effects of Formic Acid-Treated Shrimp Meal on Growth Performance and Nutrient Digestibility in Broilers

This study was conducted to know the effect of formic acid-treated shrimp meal as a protein source on growth performance, digestibilities, and nitrogen (N) retention for broilers. Shrimp meal (SM) was treated with 3% formic acid (w/v) at room temperature for 20 minutes, sun-dried, ground through a 1.0 mm mesh screen, and then ready to use as the treated SM (TSM). Forty-two male broiler chicks (8 d old, Ross 308) were randomly divided into 7 dietary groups (6 birds each), namely control diet, diets containing 5, 10, and 15% of SM, and diets containing 5, 10, and 15% of TSM and offered diets till 35 d old. Final body weight, body weight gain and feed intake decreased significantly with increasing levels of SM in diets. Feed conversion ratio also decreased with increasing levels of the SM (P&lt;0.05). Similar trend was observed in the TSM group, but the adverse effects of the TSM were milder in comparison to the SM group (P&lt;0.05). Dry matter digestibility tended to decrease (P&lt;0.05) with increasing levels of the SM but unchanged with increasing level of the TSM. Availability of ash decreased with increasing levels of the SM and TSM in diets (P&lt;0.05). Although N retention decreased (P&lt;0.05) with increasing level of the SM and TSM in diets but the decreasing trend was milder in the TSM groups than the SM groups. Moreover, chitin digestibility was significantly greater in the TSM groups than the SM groups. In conclusion, broilers received diets containing the TSM showed better growth performance along with improved nutrient digestibility and N retention which suggests that formic acid-treated SM can be used as a potential protein source in broiler diets