Insights into the mechanism of L-malic acid on drip loss of chicken meat under commercial conditions

Background A deterioration in the meat quality of broilers has attracted much more attention in recent years.L-malic acid(MA)is evidenced to decrease meat drip loss in broilers,but the underlying molecular mechanisms are still unclear.It’s also not sure whether the outputs obtained under experimental conditions can be obtained in a com-mercial condition.Here,we investigated the effects and mechanisms of dietary MA supplementation on chicken meat drip loss at large-scale rearing.Results Results showed that the growth performance and drip loss were improved by MA supplementation.Meat metabolome revealed that L-2-aminoadipic acid,β-aminoisobutyric acid,eicosapentaenoic acid,and nicotinamide,as well as amino acid metabolism pathways connected to the improvements of meat quality by MA addition.The transcriptome analysis further indicated that the effect of MA on drip loss was also related to the proper immune response,evidenced by the enhanced B cell receptor signaling pathway,NF-κB signaling pathway,TNF signaling pathway,and IL-17 signaling pathway.Conclusions We provided evidence that MA decreased chicken meat drip loss under commercial conditions.Metabolome and transcriptome revealed a comprehensive understanding of the underlying mechanisms.Together,MA could be used as a promising dietary supplement for enhancing the water-holding capacity of chicken meat.

Dietary Organic and Inorganic Selenium on Liver Glycogen and Lactate, pHu, Color and Drip Loss of Chicken Pectoralis and Gastrocnemius Muscles

The effect of selenium supplementation in finishing broiler diets on meat quality was studied. A corn soya based diet was supplemented with 0.3 ppm of Se from an organic (Seleno methionine;Se-Met) or inorganic source (sodium selenite;Se-Na) and offered to Rossmale chickens from thirty five to fifty two days old. Body weight and feed consumption were recorded during the experimental period. Immediately post sacrifice liver was removed and weight was recorded. The liver glycogen and lactate content was measured. Carcass yield and abdominal fat were determined. At 24 hours post mortem, pHu, colour L*, a*, b*, H°, C*, and drip loss of the Pectoralis and Gastrocnemius muscles were determined. Se-Met supplementation significantly decreases daily food intake. Se-Na significantly increases liver glycogen and lactate content at 3 minutes post mortem. Se-Met and Se-Na significantly increase pHu as compared to the control diet. Also a Se-Met provoked a darker (lower L*) and a redder (higher a*) and a decreased tone (lower H°) in Pectoralis. Se-Met and Se-Na significantly decrease the drip loss in Pectoralis and Gastrocnemius at 24 hours post mortem. We conclude that selenium supplementation decreases food intake and improves meat quality by improving colour and decreasing drip loss, likely by a modulation of reserve of glycogen in liver. The difference among the organic and inorganic sources is not clear and requires further investigation.

Effects of Addition of Bee Pollen on Water Holding Capacity of Pork

[ Objective] To explore the effects of different proportion of bee pollen on the water holding capacity of pork in Duroc Landrace x Yorkshire growing-finishing pigs in order to determine the optimal proportion. [ Method] A total of 80 Duroc x Landrace x Yorkshire growing-finishing pigs, weighing （10.0 ± 1.0） kg, were randomly divided into five groups. The experimental period was 120 d including the 5-day pre-feecling period. The corn-soybean meal was not replaced during the whole period. All pigs had free access to feed and water. The pigs were fasting for 24 h but not prohibited from feed before the beginning. Group I was the control group reared with the diet not supplemented bee pollen. The pigs in group II, III ,IV and V were reared with the diet supplemented bee pollen at the concentration of 1%, 3%, 5% and 7%, respectively. After slaughtering, eye muscle was used for determination of water holding capacity through fast filter paper method, drip loss method, cooking loss method and Na- pole yield determination method. [ Resultl With the increase of the proportion of bee pollen, the water holding capacity of pork was first good and then poor. The addition of bee pollen at the concentration of 5% significantly reduced the drip loss of pork and the water holding capacity which was detected by fast filter paper method, but the cooking loss and Napole yield were not significantly influenced. [ Condmion] The bee pollen can effectively improve the water holding capacity of pork in Duroc x Landrace x Yorkshire growing-finishing pigs, and the optimal proportion is 5%.

Effectiveness of dietary xylo-oligosaccharides for broilers fed a conventional corn-soybean meal diet

An experiment was conducted to investigate the effect of dietary supplementation of xylo-oligosaccharides（XOS） on growth performance, meat quality, immune functions, duodenal morphology and intestinal microbial populations of broilers fed a conventional corn-soybean meal basal diet. A total of 450 1-day-old commercial Arbor Acres male broiler chicks were randomly allocated by bodyweight to 1 of 5 treatments with 6 replicate cages（15 broilers per cage） for each of 5 treatments in a completely randomized design. Chicks were fed the basal corn-soybean meal diets supplemented with 0, 25, 50, 75, or 100 mg of XOS kg–1 of diet, respectively, for an experimental duration of 42 days. The results showed that supplementation of XOS affected feed conversion rate（feed/gain, F/G） during days 22–42 and 1–42（P〈0.03）, drip loss in thigh muscle（P=0.02）, and duodenal crypt depth（P=0.005） on day 42, but had no effect（P〉0.05） on all other measured indices. The chicks fed the diet supplemented with 100 mg of XOS kg–1 had the lowest（P〈0.05） F/G and drip loss in thigh muscle. The drip loss in thigh muscle decreased linearly（P=0.003） as the supplemented XOS increased. Duodenal crypt depth decreased（P〈0.05） at the supplemental level of 75 mg of XOS kg–1. The results indicate that dietary supplementations of 75 and 100 mg of XOS kg–1 are beneficial to broilers fed a conventional corn-soybean meal diet.

Meat Quality Parameters and the Effects of Stress: A Review

The objective of this review was to address the stress effects on meat quality considering the main attributes that involve meat quality.Animal protein production has been increasing with global demand for meat with meat quality a major concern,especially for more demanding consumers who are looking for quality products to meet their needs.The quality of the meat is the result of what happened to the animal throughout the production chain,that is,good rearing conditions result in a better meat quality.Different types of stress can be harmful to animals due to inadequate or improper animal handling on farms,inadequate transport conditions,poorly maintained trucks and roads,and conditions that agitate animals can lead to bruising,thermal stress.The stress in animals occurs when they are in adverse conditions and can significantly compromise meat quality loss.As an example,stress can significantly affect meat quality parameters as drip loss(DL),meat color,change ultimate pH and cause meat anomalies.Among the main parameters of evaluation used for meat quality are color,characterized by luminosity(L^*,a^*,b^*),lipid and protein oxidation,pH,water holding capacity(WHC)and softness.Producing and processing high-quality meat is a challenge since it is necessary to apply methods that promote comfort in a complete sense,in a way that minimizes inducing significant stress.Based on the results presented it is remarkable that stress alters the meat quality,compromising the main attributes that involve it,like color,pH,WHC,Warner-Bratzler shear force(WBSF),lipid oxidation,among others andis necessary to avoid or reduce stress caused during the production of the animals to ensure a high-quality meat,resulting in greater profitability for the producer.

Effect of quantum therapy on pork quality

In this study the impact of quantum therapy on meat quality of slaughtered pigs was investigated.For this purpose the pigs were treated with different doses of magnet-infrared-laser(MIL) radiation.Animals were divided into four groups according to radiation doses(4096,512,and 64 Hz,and control without application),which were applied in the lumbar area of musculus longissimus dorsi(loin) at various time intervals prior to the slaughter(14 d,24 h,and 1 h).Animals were slaughtered and the meat quality was evaluated by determining of pH value(1,3,and 24 h post slaughter),drip loss,colour,and lactic acid and phosphoric acid amounts.MIL therapy can be used in various fields of veterinary medicine as are surgery and orthopaedics,internal medicine,dentistry,pulmonology,gastroenterology,gynaecology,urology,nephrology,and dermatology.The results achieved showed that MIL radiation used in a short period before slaughter(1 h) can cause a change in the meat quality,as reflected by the non-standard development of pH values,increases in drip loss,and changes of meat colour.