Effect of ambient storage of wheat samples on their nutritive value for chickens

1. Two wheat cultivars (Abbott and Equinox) were grown using the same crop husbandry conditions. Batches of each cultivar were stored at ambient temperature (AT) for 0, 6, 12, 18 or 24 weeks. Those stored at AT for less than 24 weeks were then stored at -20 degrees C up to the end of the storage period. The 24 week (AT) samples were divided into two lots and one lot was frozen to -20 degrees C for 24 h. 2. Each of the 12 wheat samples was included (650 g/kg) in a nutritionally complete diet and fed to broiler chickens from 7 to 21 d of age. The apparent metabolisable energy (AME) of each sample was determined using a rapid bioassay with adult cockerels. 3. The Equinox cultivar sample had a high proportion (92/1000) of visibly sprouted grains and had a low Hagberg falling number (high amylase activity) and high content of free sugars compared to the Abbott sample. There were no major changes in dry matter, free sugar content, water extract viscosity or Hagberg falling number due to the different times of ambient storage of either of the two wheat cultivar samples. 4. The chickens fed on the Abbott cultivar wheat had a greater weight gain, although there were no differences in the determined AME of the two wheat cultivars. 5. The Abbott sample stored at ambient temperature for 6 weeks had a greater AME than the sample given no ambient storage and the samples given 18 and 24 weeks ambient storage. There were no significant differences between the Equinox cultivar samples. There were no effects of storage time on the growth performance of the broiler chickens. 6. The AME of the unfrozen Abbott cultivar was greater than the frozen (for 24 h) sample but there was no effect on broiler growth performance. This study suggests that, in some wheat samples, there may be a benefit in avoiding freezing during storage.     

Influence of preservation methods on the quality of colostrum sourced from New Zealand dairy farms

Abstract

AIMS: To assess the effect of two temperatures (ambient temperature and 4°C), three preservation methods (no preservative, yoghurt and potassium sorbate), and two periods of storage (3 and 7 days) on Brix and total bacterial and coliform counts of colostrum collected from New Zealand dairy farms.

METHODS: One litre of colostrum destined to be fed to newborn calves was collected from 55 New Zealand dairy farms in the spring of 2015. Six aliquots of 150 mL were obtained from each colostrum sample, with two aliquots left untreated, two treated with potassium sorbate and two with yoghurt, and one of each pair of aliquots stored at ambient temperature and the other at 4°C. All samples were tested for Brix, total bacterial counts and coliform counts before treatment (Day 0), and after 3 and 7 days of storage. The effect of preservation method and storage temperature on the change in Brix, bacterial and coliform counts after 3 or 7 days of storage was analysed using multivariable random effects models.

RESULTS: For all outcome variables there was a temperature by preservation interaction. For aliquots preserved with potassium sorbate, changes in Brix and bacterial counts did not differ between aliquots stored at ambient temperature or 4°C, but for aliquots preserved with yoghurt or no preservative the decrease in Brix and increase in bacterial counts was greater for aliquots stored at ambient temperature than 4°C (p<0.001). For aliquots preserved with potassium sorbate, coliform counts decreased at both temperatures, but for aliquots preserved with yoghurt or no preservative coliform counts increased for aliquots stored at 4°C, but generally decreased at ambient temperatures (p<0.001). There was also an interaction between duration of storage and temperature for bacterial counts (p<0.001). The difference in the increase in bacterial counts between aliquots stored at 4°C and ambient temperature after 3 days was greater than between aliquots stored at 4°C and ambient temperature after 7 days.

CONCLUSIONS AND CLINICAL RELEVANCE: Use of potassium sorbate to preserve colostrum for 3 or 7 days resulted in little or no reduction in Brix and a lower increase in total bacterial counts than colostrum stored without preservative or with yoghurt added. Colostrum quality was not affected by storage temperature for samples preserved with potassium sorbate, but storage at 4°C resulted in better quality colostrum than storage at ambient temperatures for colostrum with no preservative or yoghurt added.     

Effect of storage temperatures and duration on quality of prepared chicken breast with paprika oleoresin

The objective of this study was to investigate the effect of storage temperatures and time on discoloration and oxidation of prepared chicken breast with paprika oleoresin. Freshly prepared chicken breast containing paprika oleoresin was stored at ?2, ?10, ?18°C, and an oscillating temperature between ?10 and ?18°C (?10/?18°C). A significant decrease in redness was detected at ?2, ?10, and ?10/?18°C. The lowest TBARS values and carbonyl contents were observed in the samples stored at ?18°C for 5 weeks. Also, the values of sulfhydryl groups gradually decreased with the increase in storage temperatures and duration. The results suggest a positive correlation between the loss of redness and oxidation in all samples. The findings indicated that the discoloration and oxidation of prepared chicken breast added with paprika oleoresin were inhibited significantly when stored at ?18°C.     

Effect of dietary vitamin E on broiler meat qualities,color, water‐holding capacity and shear force value,under heat stress conditions

This study was conducted to evaluate the effect of dietary vitamin E (VE) on broiler meat quality, especially focused on PSE (pale color, soft and exudative), under chronic heat stress (HS) conditions. Twenty‐eight‐day‐old female Ross broilers were kept in independent cages with a controlled temperature of 24°C (normal temperature: NT) or 30°C (high temperature: HT). The NT chickens were fed basal feed. The HT chickens were fed basal feed (HT) or VE (200 mg/kg) added feed (HT + E). Broilers were weighed and slaughtered at 38 days old. The breast muscle was removed immediately and then the samples were used for determination of meat color, pH, water holding capacity (WHC) and shear force value (SFV). Body weight gain and feed intake were significantly decreased in the HT and HT + E groups compared to the NT group. VE supplementation did not affect the growth performance. Chronic HS at 30°C for 10 days may cause deterioration of meat quality such as PSE. The effects of chronic HS on meat quality were most significant in the toughness of broiler breast meat. Supplementation of VE in broiler feed would be effective to prevent the extent of PSE on broiler meat by chronic HS.     

Effects of diurnally cycling versus constant temperatures on chicken growth and food intake

1. Male broiler chickens were exposed in separate experiments to: (a) constant ambient temperatures (Ta) ranging between 10 and 35°C; (b) 12 h: 12 h diurnal high‐low temperature of 10:30°C, 15:35°G and 15:30°C in different trials; and (c) 12 h of 30 or 35°G and 12 h of variable lower temperature.

2. A progressive decline in weight gain and food intake was obtained as Ta increased from 18 to 35°C. Under diurnally cycling temperature, weight gain and food intake were lower than in the average corresponding constant temperature, with the exception of chickens exposed to 15:30°C, where weight gain and food intake were not significandy different from those of the constant average temperature.

3. As the diurnal cold period was made colder, chickens exposed during half of the diurnal cycle to high temperature (30, 35°C) demonstrated a significant (P ≤ 0.05) increase in weight gain and food intake.

4. There was a good correlation between plasma triiodothyronine (T3) and Ta. The correlation between T3 and food intake was highly significant, but that between T3 and weight gain was poor.

5. The results indicate the difficulties in predicting the performance of broilers exposed to diurnally cycling temperatures from knowledge of the average temperature.     

Alleviative effects of α-lipoic acid supplementation on acute heat stress-induced thermal panting and the level of plasma nonesterified fatty acids in hypothyroid broiler chickens

1. The present study was conducted to examine the effects of α-lipoic acid on hypothyroidism-induced negative growth performance and whether α-lipoic acid alleviates acute heat stress in relation to hypothyroid status.

2. Female broiler chickens (14?d-old) were fed diets supplemented with α-lipoic acid (100?mg/kg) and an antithyroid substance, propylthiouracil (200?mg/kg), for 20?d under thermoneutral conditions (25°C). At 42?d of age, chickens were exposed to a high ambient temperature (36°C, 60% RH) for 4?h.

3. Under the thermoneutral condition, propylthiouracil administration decreased feed efficiency and concomitantly increased adipose tissue and thyroid gland weights. Plasma nonesterified fatty acids and triacylglycerol were also increased by propylthiouracil administration. However, α-lipoic acid supplementation did not affect the hypothyroidism-induced effects.

4. In hypothyroid chickens, the rise in respiratory rate induced by heat exposure was greatly inhibited by α-lipoic acid administration at 1?h, but this effect had disappeared at 4?h. In addition, a similar inhibitory effect on the concentrations of plasma nonesterified fatty acids was subsequently observed at 4?h.

5. Therefore, the present study suggested that α-lipoic acid alleviates acute heat stress if chickens are in a hypothyroid status.     

The influences of ambient temperature and crude protein levels on performance and serum biochemical parameters in broilers

This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28–32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially.     

Effects of astaxanthin‐rich dried cell powder from Paracoccus carotinifaciens on carotenoid composition and lipid peroxidation in skeletal muscle of broiler chickens under thermo‐neutral or realistic high temperature conditions

Thirty‐two 15‐day old broiler chicks (Chunky strain ROSS 308) were randomly divided into four treatments in a 2 × 2 factorial design. The main factors were diet (basal diet or basal diet supplemented with 0.15% astaxanthin‐rich dried cell powder (Panaferd‐P [astaxanthin 30 ppm]) and ambient temperature (thermo‐neutral [25 ± 1°C] or high [35 ± 1°C for 6 hr]). Dietary supplementation with Panaferd‐P did not affect growth performance, though high ambient temperature decreased feed intake and the weight of breast tender muscle, liver, and heart. High ambient temperature also decreased redness in both breast and leg muscles of chickens, while Panaferd‐P increased redness and yellowness of breast and leg muscles of chickens. Panaferd‐P increased Paracoccus carotinifaciens‐derived pigments (i.e., adonixanthin, astaxanthin, adonirubin, and cantaxanthin) as well as corn‐derived pigments such as zeaxanthin and lutein in breast and leg muscles. High ambient temperature increased the malondialdehyde (MDA) concentration in breast muscle, while Panaferd‐P decreased the MDA concentration in breast muscle under both temperature conditions. Our results suggest that dietary supplementation with Panaferd‐P increases muscle carotenoid content, the redness and yellowness of meat and decreases the muscle MDA concentration in broiler chickens kept under thermo‐neutral or high ambient temperature conditions.     

Incidence and classification of early embryonic mortality in broiler breeder chickens

1. Unusually high early embryonic mortality (EEM) was observed in hatching eggs from broiler compared with white or brown table‐egg breeders in Atlantic Canada. Broiler breeder EEM in Atlantic Canada was twice the EEM in broiler breeders from other areas of North America.

2. Comparisons of holding temperatures (18 and 30°C) for 24 h after egg collection, in combination with a storage time of 0 or 7 d at 18°C prior to incubation, were made using the criteria: embryo development (stage), and size at 0, 3, 6 and 9 d incubation, EEM, late embryonic mortality (LEM) and hatchability (HAT).

3. Stage of development of embryos, at 0 d incubation, was highest for eggs held for 24 h at 30°C and stored for 7 d. Embryo stage, weight and length at 3, 6 and 9 d incubation were positively correlated.

4. Hatchability of fertile eggs was lowest (66.5%) for eggs held for 24 h at 30°C and stored for 7 d and highest (87.2%) for eggs held for 24 h at 18°C and stored for 0 d. Holding temperature and storage time significantly influenced EEM and LEM.

5. EEM classification differed for strain of breeder. In broiler breeders the majority of the EEM was at a relatively late stage of development (exhibiting an obvious blood ring with a visible embryo). In comparison, EEM from table egg breeders was distributed equally among three categories.     

Early-age cold conditioning of broilers: effects of timing and temperature

1. The aim of the present study was to determine the effects of early-age cold conditioning (CC) on performance, ascites mortality, thyroid hormones status and immune response (leucocytes count) of broiler chickens.

2. A total of 336 chicks at 2 and 3?d of age were exposed to 20 or 25°C (for 3 or 6?h) in a 2?×?2?×?2 factorial experiment, while a control group was kept under normal temperature conditions (30°C). Thereafter, both control and cold conditioned birds were reared under standard conditions until 42?d of age.

3. The results showed that performance (weight gain and feed efficiency) was improved by CC at the end of the rearing period. Carcase traits (breast, thigh and abdominal fat percentage) were not affected by different treatments. Heart weight was lower in cold conditioned birds accompanied with lower ascites mortality. Total leucocyte count was higher in CC birds. Higher concentrations of thyroxin (T₄) were found in plasma of treated groups, while triiodothyronine (T₃) to T₄ ratio was decreased.

4. In conclusion, it seems that early age CC improves performance and reduces ascites mortality of broilers through altered thyroid hormones metabolism and leucocyte function. According to the results, the best timing for CC of broilers was 20°C for 6?h at the age of 2?d, and no significant benefit was observed by repeated CC.     

Effect of low-temperature drying on the nitrogenous compounds and inositol phosphates in broiler chickens and cecectomized laying hen excreta

We investigated how the chemical composition of broiler chicken and cecectomized laying hen excreta is affected by drying in a forced-air drying chamber at low temperatures. Excreta that was immediately frozen after voiding provided the reference values. The excreta were dried in drying chambers for 4 hr, 6 hr, and 12 hr at 23°C or 33°C in the broiler experiment and 19°C or 29°C in the cecectomized laying hen experiment. The total N and inositol phosphate concentrations in the excreta of broiler chickens and cecectomized laying hens were not influenced (p > .050), except for one inositol tetrakisphosphate isomer (p = .026) in broilers. Compared to fresh excreta, drying did not affect the ammonia concentrations in the cecectomized laying hen experiment (p > .050), but the ammonia concentration was lower when dried for 12 hr at 33°C in the broiler experiment (p = .002). Amino acid concentrations in cecectomized laying hen excreta decreased until 4 hr of drying and then increased at both drying temperatures (p < .001). The results indicate that the applicability of drying poultry excreta at low temperatures in forced-air drying chambers to determine the chemical compound concentrations is trait-dependent. Future studies are necessary to investigate whether these results are also dependent upon the amount of excreta stored in the drying chambers.     

Phytase dose effects in practically formulated diets that vary in ingredient composition on feed manufacturing and broiler performance

Considering approaches to efficiently produce broiler chickens, an experiment was conducted to describe the manufacturing and feeding effects of a corn, soybean meal, and wheat based diet with varying levels of corn distillers dried grains with solubles (DDGS) and commercial phytase. Treatments were arranged in a 3 × 2 factorial randomized complete block design varying in phytase (zero, 1,000, and 6,000 FTU/kg) and DDGS inclusion (zero or 5%). Phytase inclusion decreased dietary non-phytate phosphorous (nPP) and total Calcium (Ca) in formulation by 0.12 and 0.1%, respectively. Diets were steam conditioned at 82°C for 10 s, extruded through a 4.7 × 38 mm pellet die, and fed as crumbles (starter and grower) or pellets (finisher). Ten replicate pens of straight-run Hubbard × Cobb 500 chicks consumed one of 6 dietary treatments for 38 days. Phytase improved feed conversion ratio (FCR) in the starter period (P = 0.05), but benefits were not apparent in the grower or finisher periods. Phytase and formulation main effects interacted to affect overall FCR (P = 0.05), demonstrating a 0.05 decrease in FCR when birds were fed a diet containing a super-dose of phytase and without DDGS relative to diets containing a super-dose of phytase and DDGS. The DDGS likely provided reduced nutrient availability relative to their nutrient values used for diet formulation or provided non-starch polysaccharides (NSP) at a level that decreased bird performance. Based on tibia ash measures, performance improvement associated with the super-dose of phytase was likely associated with reducing phytate phosphorus gastrointestinal irritation rather than meeting bird phosphorus requirement.     

The radiation pasteurisation of broiler chicken carcasses

Irradiation of standard broiler carcasses within 24 hr. of slaughter with a dose of 0.15 Mrad of gamma radiation was sufficient to give a shelf life of more than six days at 5° C. followed by one day at 15° C. The carcasses were treated and stored in air and remained unchanged in appearance and odour. After cooking, treated and stored carcasses were indistinguishable, when tasted in blind comparison tests, from un‐irradiated material held at —20° C. for the same time. The storage conditions chosen were taken to represent the upper limits of commercial and domestic handling during distribution of unfrozen broiler chicken. The economics of the radiation process are discussed.     

Feed can be a source of Campylobacter jejuni infection in broilers

1. The aim was to determine the importance of a contaminated diet as a possible cause of Campylobacter jejuni infection in broilers.

2. This study evaluated the viability of C. jejuni in both starter and finisher diets and the interference from other mesophilic bacteria in this viability.

3. Starter and finisher samples of broiler diet were deliberately contaminated with 3 or 5 log CFU·g^?1 of C. jejuni (NCTC 11351) and then maintained at two different storage temperatures (25°C or 37°C) for 3 or 5 d.

4. C. jejuni survived during this period and, when inoculated at 10³ CFU·g^?1, multiplied with greater proliferation at a storage temperature of 37°C. There was no relationship between the amount of mesophilic bacteria and C. jejuni viability.

5. This study highlights the importance of the diet in the epidemiology of C. jejuni in broilers.     

Evaluation of epididymis storage temperature and cryopreservation conditions for improved mitochondrial membrane potential,membrane integrity,sperm motility and in vitro fertilization in bovine epididymal sperm

The maintaining of the epididymis at lower temperatures during storage and transport improves sperm quality. Our study aimed to test whether epididymis storage temperature (post‐mortem) and sperm cryopreservation affect sperm kinetics, membrane integrity, mitochondrial potential and fertility capacity. Thirty‐six epididymides were collected from 18 bulls after slaughter and divided into two groups: at 4 or 34°C for 2–3 hr. The sperm was collected from the epididymis cauda. The evaluation consisted of computer‐assisted sperm analysis (CASA), SYBR14/PI/JC1 to evaluate membrane integrity, mitochondrial membrane potential (MMP) and measurement of lipid peroxidation (TBARS). The sperm was then frozen using an automatic device. After thawing, sperm samples were evaluated by the same variables and further in vitro fertilization rates. Cryopreservation negatively affected sperm motility in samples stored at 4 and 34°C. Nevertheless, the 4°C samples yielded higher rates of blastocyst formation. Pre‐freeze sperm motility, progressive motility and velocity were higher in sperm from epididymis stored at 4°C while post‐thaw sperm motility, progressive motility and velocity remained the same among samples from epididymis stored at 4 or 34°C. However, with regard to the kinetic patterns, samples collected from epididymis stored at 34°C had lower values when compared to those stored at 4°C prior the cryopreservation process. Our results indicate that epididymis handling conditions after cryopreservation may affect sperm quality after thawing, especially due to compromised MMP in sperm collected from epididymis stored at higher temperatures.     

The effect of processing and marketing procedures on the bacteriological condition and shelf life of eviscerated turkeys

Experiments carried out in a turkey processing plant showed that there was a fivefold increase in the number of psychrophilic bacteria present after holding eviscerated carcasses in static slush ice tanks for 24 hr. The predominant bacteria in the 24 hr chill tanks were strains of Flavobacterium, Cytophaga and Pseudomonas.

The carcasses were wrapped in heat‐shrunk‐oxygen‐impermeable film and after freezing packed in individual boxes and held at ‐20° C. The storage life at 1°, 10° and 20° C. was determined together with the time taken for the frozen carcasses to equilibrate to these temperatures. It was found that at 1° C. the carcasses kept for about 3 weeks, but at 10° C. they spoiled within 7 days and at 20° G. within 3 days.

An analysis of the spoilage flora showed that although Pseudomonas strains predominated on the turkeys stored at 1° C. fewer were isolated from turkeys stored at 10° C. and 20° C. At these two temperatures an organism identified as Enterobacter liquefaciens predominated together with atypical lactobacilli resembling unidentified strains previously described by Thornley and Sharpe (1959).     

Effects of ambient temperature on growth performance and carcass traits of male growing White Pekin ducks

ABSTRACT

1. An experiment was conducted to investigate the effects of ambient temperature on growth performance and carcass traits in male growing Pekin ducks from 14 to 42 d of age in order to establish their optimal temperature requirements.

2. A total of 216 14 d old male White Pekin ducks were allocated randomly to six environmentally controlled chambers with ambient temperature set at 20°C, 22°C, 24°C, 26°C, 28°C, and 30°C from 14 to 42 d of age, respectively.

3. As ambient temperature increased from 20°C to 30°C, the body weight and weight gain decreased linearly or quadratically (P < 0.05) and was accompanied by linearly decreasing feed intake (P < 0.05). According to broken-line regression, the upper critical level of ambient temperature during the growing period for body weight, weight gain, and feed conversion ratio were 27.4°C, 27.4°C, and 26.0°C, respectively.

4. The weight of breast meat, leg meat, and abdominal fat decreased linearly or quadratically as ambient temperature increased and declined to a minimum when the temperature increased to 30°C (P < 0.05). The percentage of breast meat and abdominal fat showed a linear or quadratic decreasing response to increasing temperature, but leg meat percentage increased as temperature increased and reached maximum at 30°C (P < 0.05). According to broken-line regression, the upper critical ambient temperatures during the growing period for breast meat weight and percentage were 25.5°C and 25.6°C, respectively.

5. It was concluded that both growth performance and breast meat of growing ducks were sensitive to increasing ambient temperature and this should be kept below the upper critical temperature during the growing period in order to optimise growth performance and carcass traits at market age.     

肉鸡能量需要动态模型的建立和参数估计

本研究通过两个试验评价肉仔鸡的能量需要。试验1选用36只AA肉仔鸡新生雏笼养6周,分别于3周龄和6周龄评定2种饲粮的表观代谢能(AME)和表观氮校正代谢能(AMEn)。结果表明:氮校正使AME降低5%左右,AMEn和AME的相关性较强。试验2选用AA肉鸡新生雏240只,公母分饲笼养6周,每周测定空腹体重及采食量。用Compertz方程拟合公母鸡的生长曲线,微分建立日增重与日龄的函数关系,再与利用一元线性回归法建立的能量需要模型组合,形成动态的能量需要预测机制。     

Effects of storage conditions on hatchability of chicken eggs in a warm climate

1. A total of 3792 eggs from AF Bosbek layer parents were used to determine the effect of storage time on the hatchability of eggs kept either small end up (SEU) or small end down (SED).

2. These eggs were stored at room temperature (27°C‐31°C) or in an air‐conditioned room (20°C‐23°C), for two, three, six or seven days and incubated in four replicate hatches.

3. Eggs kept SEU improved hatchability even for short‐term storage when temperatures were high.

4. Simple air‐conditioning can reduce the temperature sufficiently for the viability of the embryo to be preserved for up to a week.     

In vitro and in vivo assessment of the effect of initial moisture content and drying temperature on the feeding value of maize grain

1. This study assessed the impact of drying temperature (54, 90, and 130°C) and maize grain moisture content at harvest (36% and 29%) on in vitro digestibility, the growth performance and ileal digestibility of broiler chickens.

2. In contrast to the results from the in vitro digestibility, apparent ileal digestibility of starch and energy decreased when the drying temperature was raised from 54 to 130°C, and this effect was more pronounced in maize grain harvested at high initial moisture content (36%). Ileal protein digestibility of maize grain decreased significantly when dried at the intermediate temperature (90°C) and with a high harvest moisture content (36%). Drying temperature and initial moisture content did not significantly affect AMEn.

3. When maize was dried at 130°C, the particle sizes of flour recovered after standard milling procedures decreased significantly, which would influence animal growth performance and in vivo digestibility through animal feed selection.