Effects of xylanase and antibiotic addition on ileal and faecal apparent digestibilities of dietary nutrients and evaluating HCl-insoluble ash as a dietary marker in growing pigs

Reliability of acid-insoluble ash as internal marker for the measurement of digestibility in rabbits

<p>The present study aimed to evaluate acid-insoluble ash (AIA) as an internal marker for the measurement the coefficient of total tract apparent digestibility (CTTAD) in rabbits through two experiments (E1 and E2). In E1, 48 rabbits were used to calculate the CTTAD of the same basal diet according to the European reference method (ERM), the AIA and the titanium dioxide (TiO₂ with 1 g of TiO₂/kg diet) techniques (n=16 rabbits/method). The effect of feed sample quantity on dietary AIA content was investigated and total collection of faeces was carried out to calculate marker recovery. In E2, 48 rabbits were allotted to three groups fed diets with no sugar beet pulp (SBP0) or with 100 (SBP100) and 200 (SBP200) g sugar beet pulp/kg (n=16 rabbits/group). Each group was divided into two subgroups, ERM and AIA (n=8 rabbits/subgroup), in which CTTAD was measured using the European reference and AIA method, respectively. In AIA subgroups, only 10% of the total daily faecal output was sampled from 9:00 to 9:30 am. Feed analysis in E1 showed that increasing sample quantity from 5 to 9 g did not affect the dietary AIA content; however, the analytical error was 7 and 5 times lower (<em>P</em>&lt;0.05) for 9 g, when compared to 5 and 7 g samples. Feed analysis also showed 1.030±0.003 g TiO₂/kg diet. Faecal marker recovery was 99.80±0.03 and 96.89±0.16% for AIA and TiO₂, respectively. The CTTAD of dry matter (DM), did not differ between methods in E1, but a 5-fold higher variability (<em>P</em>&lt;0.05) was observed for the TiO₂ technique in comparison with the ERM and AIA methods. Also, no differences in the CTTAD of DM between the ERM and AIA methods were found in E2. In conclusion, AIA is a reliable internal marker in rabbits and offers the possibility of measuring the CTTAD of diets with precision, when complete faecal collection or feed intake measurement is not possible.</p>

Environmental Sustainability Analysis and Nutritional Strategies of Animal Production in China

Animal production in China has achieved considerable progress and contributes to 46% of the total agriculture output value of the country. However, this fast expansion of animal production has led to environmental pollution. In this article, we review the status of soil, water, and air pollution associated with animal production in China and analyze the main sources of the pollutants. The government has promulgated regulations and standards, and effective models and technologies have been developed to control pollution during the last 10 years. Because nutrition and feed strategies represent the most effective method of controlling environmental pollution at the source, this review focuses on nutritional technologies, including accurate feed formulation, rational use of additives, and proper processing of feeds. The advances of modern biotechnology and big data systems also provide more modern approaches to decreasing wastage release. These nutritional strategies are expected to promote sustainable development of animal production.

Performance, nutrient digestibility and intestinal disaccharidase activity of weaner/grower pigs given diets containing extruded Chinese stored brown rice with exogenous enzyme supplements

One performance and one ileal apparent digestibility (IAD) trial were conducted to investigate the performance, nutrient digestibility and intestinal disaccharidase activity of weaner/grower pigs given diets containing Chinese stored brown rice (CSBR) extruded and with exogenous enzyme supplements. In experiment 1, 96 crossbred (Duroc X Landrace X Large White) piglets weaned at 24 days of age were randomly divided into four groups according to a 2 X 2 factorial design. The animals were given four diets: (1) CSBR without enzyme supplementation, (2) CSBR supplemented with 625 mg a-amylase (2509 enzyme activity units) and 200 mg glucoamylase per kg (20018 enzyme activity units) per kg diet, (3) a normal temperature extruded CSBR (NTECSBR) without enzyme supplementation, and (4) NTECSBR supplemented with 625 mg a-amylase (2508 enzyme activity units) and 200 mg glucoamylase (20010 enzyme activity units) per kg diet. Growth, food consumption and specific activity of disaccharides in sections of the digestive tract were measured. In experiment 2, six male grower pigs with a mean initial body weight 21 kg, fitted with a simple ‘T’ cannula at the terminal ileum were used in a 6X6 Latin-square design. In addition to CSBR and NTECSBR diets with and without enzymes, a low temperature extruded diet LTECSBR with and without enzymes (as for other diets) was introduced. IAD of nutrients was measured. Extrusion resulted in a poorer (P < 0.05) food/gain for weaned pigs. Extrusion and enzyme supplementation had no influence (P > 0.05) on average daily food intake and average daily gain. Extrusion tended to improve (P = 0.075) IAD of starch but IAD of energy, dry matter, crude protein and amino acids were not influenced (P > 0.05). Enzyme supplementation had no effect on IAD of amino acids (P > 0.05), except for increasing IAD of lysine, threonine and isoleucine (P < 0.05). Extrusion and enzyme supplementation resulted in a higher (P < 0.05) maltase activity in the duodenum at day 14 of the trial. However, extrusion decreased (P < 0.05) the activity of maltase, isomaltase, sucrase and lactase in the jejunum at day 28. Enzyme supplementation increased (P < 0.05) the activities of maltase, isomaltase, trehalase and lactase in the jejunum at day 28. There was a positive extrusion X enzyme interaction (P < 0.05) for the activity of maltase and trehalase in the duodenum at day 14; a negative interaction was observed for the activity of lactase, maltase, isomaltase and trehalase in the jejunum at day 28. The results suggest that neither extrusion nor enzyme supplementation are necessary for CSBR to be used in pig diets.

Chromic oxide and acid-insoluble ash as markers in digestibility studies with growing pigs and sows

The results of three experiments, focused on the determination of endogenous ileal flow (EIF) of amino acids (AA) and nitrogen (N) (Exp. 1), apparent ileal digestibility (AID) of AA and N (Exp. 2), and apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), N, calcium (Ca) and phosphorus (P) (Exps. 2 and 3), were used to compare chromic oxide (Cr₂ O₃ ) and acid-insoluble ash (AIA) as digestibility markers. In Exps. 1 and 2, a total of six gilts fitted with T-cannula in terminal ileum, and in Exp. 3, a total of 24 pregnant sows were used. In Exps. 1 and 2, the pigs were assigned into four dietary treatments according to 4 × 6 crossover design (Exp. 1; diets with 0%, 4%, 8% and 12% of casein; Exp. 2 basal diet with different levels of phytase). In Exp. 3, the sows were assigned to four dietary treatments (basal diet with different levels of phytase) of six sows. In Exps. 1 and 2 ileal digesta and in Exps. 2 and 3 faeces were collected for the determination of EIF, AID and ATTD. Differences in EIF of AA determined by Cr₂ O₃ and AIA ranged (p ˃ 0.05) from -4.62 to 4.54%. The lowest EIF was for methionine and the greatest one for proline, determined by both markers. Apparent ileal digestibility determined by Cr₂ O₃ was slightly greater (p ˃ 0.05) in comparison with AIA. Differences ranged from 1.88% (Arg) to 7.08% (Gly). The greatest AID was for arginine and the lowest one for glycine, determined by both Cr₂ O₃ and AIA. Similarly for ATTD of DM, OM, N, Ca and P, there were no differences in digestibility determined by Cr₂ O₃ and AIA. Both, Cr₂ O₃ and AIA, are suitable and comparable markers for digestibility studies in pigs.

Evaluation of two external markers for measurement of ileal and total tract digestibility of pigs fed human-type diets

External markers for determination of nutrient digestibility have often been evaluated in conventional dry feeds but less often in conventional feeds such as human-type diets used in animal model studies. In the present study, 5 ileal-cannulated pigs were fed 5 types of soft bread-based diets supplemented with Cr(2)O(3) and AIA as digestibility markers for 1 wk in a Latin square design. Ileal contents were collected twice for 5 h and a fecal grab sample was obtained once per week. Ileal and total tract digestibility of OM and nonstarch polysaccharides (NSP) based on the 2 markers were compared by linear regression. Across dietary treatments and site of collection, high correlation existed between digestibility values obtained with Cr(2)O(3) and AIA, resulting in a R(2) > 0.77 (P < 0.001) and a linear relation close to unity. For ileal samples, the correlation was poor, particularly for NSP, which had R(2) = 0.09 (P = 0.14) whereas OM had an R(2) = 0.52 (P <0.001). On the other hand, fecal grab samples led to R(2) > 0.92 (P < 0.001) for both OM and NSP. However, AIA gave higher values than Cr(2)O(3), particularly in samples with lower digestibility. The discrepancy is presumably caused by analytical difficulties due to a high fecal ash contents or interference with other components in the human-type diets.

Effects of folic acid on the performance of suckling piglets and sows during lactation

BACKGROUND

The present research was conducted to investigate the influences of supplementation with different levels of folic acids in diet on the performance of lactating sows. Twenty Landrace × Yorkshire sows received the same basal corn-soybean diets (folic acid, 1.3 mg kg(-1)) from gestation to parturition (day 107). After parturition, sows were allotted to four treatments: control group (folic acid supplementation level, 0 mg kg(-1)), group 1 (12.5 mg kg(-1)), group 2 (50 mg kg(-1)) and group 3 (100 mg kg(-1)), with five replicates of one sow. The experiment lasted for 21 days.

RESULTS

(1) Folic acid increased milk production (P > 0.05). (2) Compared with the control, supplementation with folic acid (100 mg kg(-1)) increased the concentration of butter fat, total substance and non-lipoid substance significantly (P < 0.01), the concentration of milk protein was also significantly increased in group 2 and group 3 (P < 0.01) in milk. (3) Folic acid supplementation could increase litter weaning weight, average piglet weaning weight and average piglet daily gain (P > 0.05).

CONCLUSION

These results suggested that supplementation with folic acid in the diets of lactating sows increases milk production, improved milk quality and the performance of piglets.