Effects of post-hatch brooding temperature on performance of starter and growing Pekin ducks

Effects of ambient temperature on growth performance, slaughter traits, meat quality and serum antioxidant function in Pekin duck

The present study investigated the effects of temperature on growth performance, slaughtering traits, meat quality and antioxidant function of Pekin ducks from 21-42 d of age. Single factor analysis of variance was used in this experiment, 144 21 d-old Pekin ducks were randomly allotted to 4 environmentally controlled chambers: T20 (20°C), T23 (23°C), T26 (26°C) and T29 (29°C), with 3 replicates in each group (12 ducks in each replicate), the relative humidity of all groups is 74%. During the 21-day trial period, feed and water were freely available. At 42 d, the BW (body weight) and ADG (average daily gain) of T26 were significantly lower than T20 (p < 0.05), and the T29 was significantly lower than T20 and T23 (p < 0.05). The ADFI (average daily feed intake) of T26 and T29 were significantly lower than T20 and T23 (p < 0.05). Compared to the T29, the T20 showed a significant increase oblique body length and chest width, and both the keel length and thigh muscle weight significantly increased in both the T20 and T23, while the pectoral muscle weight increased significantly in other groups (p < 0.05). The cooking loss of the T29 was the lowest (p < 0.05). The T-AOC (total antioxidant capacity) of T29 was significantly higher than the other groups (p < 0.05), the SOD (superoxide dismutase) in the T29 was significantly higher than the T23 and T26 (p < 0.05). In conditions of 74% relative humidity, the BW and ADFI of Pekin ducks significantly decrease when the environmental temperature exceeds 26°C, and the development of body size and muscle weight follows this pattern. The growth development and serum redox state of Pekin ducks are more ideal and stable at temperatures of 20°C and 23°C.

Brooding Temperature Alters Yolk Sac Absorption and Affected Ovarian Development in Goslings

In order to explore the brooding temperature on the absorption of yolk sac and the ovary development of goslings, 126 1-day-old female goslings were randomly divided into three groups with three replicates in each group. The brooding temperatures were set at 32 °C, 29 °C and 26 °C (represent G32, G29 and G26), respectively, in each group. At 48, 60 and 72 h, two goslings from each replicate were weighed, and the yolk sac was collected and weighed. The fatty acid composition of yolk sac fluid was determined by gas chromatography-mass spectrometry (GC-MS). At 1, 2, 3, and 4 weeks of age, goslings from each replicate were weighed, the ovaries were weighed and fixed for hematoxylin-eosin (HE) staining, Cell cycle checkpoint kinase 1 (CHK1), fibroblast growth factor 12 (FGF12) and Sma-and Mad-related protein 4 (SMAD4) which related to regulation of ovarian development were determined by qRT-PCR. The body weight of G29 and G26 was significantly higher than that of G32 at 72 h (p < 0.05). The contents of C14:0, C16:0, C18:2n6c and total fatty acid (ΣTFA) from G32 were significantly higher than that of G26 (p < 0.05), and the contents of C18:1n9t and C22:0 in G29 were significantly higher than that of G26 (p < 0.05). The ovary index, ovary and body weight were significantly higher in G29 than those of G32 and G26 at 2 weeks of age (p < 0.05). The number of primordial follicles, number of primary follicles and diameter of primary follicles were significantly higher in G29 than those in G32 and G26 at 4 weeks of age (p < 0.05). In G29, the expression of CHK1 and SMAD4 was significantly higher than that in G32, and the expression of FGF12 and SMAD4 was significantly higher (p < 0.05) than that in G26 at 2 and 4 weeks of age. In conclusion, brooding temperature at 29 °C could promote the absorption of fatty acids in yolk sac, body weight gain, and ovarian development through up-regulating the expression of CHK1, FGF12 and SMAD4.

Effects of ambient temperature on the growth performance, fat deposition, and intestinal morphology of geese from 28 to 49 days of age

This study was conducted to investigate the effects of ambient temperature on the growth performance, fat deposition, and intestinal morphology of geese from 28 to 49 d of age. A total of 120 twenty-eight-day-old geese were randomly allotted to 5 environmentally controlled chambers with ambient temperatures set at 18, 21, 24, 27, and 30°C from 28 to 49 d of age, respectively. The feed intake, 49 d body weight, and weight gain decreased linearly or quadratically (P < 0.05) as ambient temperature increased and declined to a minimum when the temperature increased to 30°C. The feed/gain showed a linear or quadratic (P < 0.05) increasing response to increasing temperature. According to broken-line regression, the upper critical levels of ambient temperature from 28 to 49 d of age for weight gain and feed intake were 25.19 and 23.97°C, respectively. As ambient temperature increased from 18 to 30°C, the abdominal fat weight, abdominal fat rate, and subcutaneous fat thickness decreased linearly (P < 0.05) and were accompanied by linearly increasing liver fat content (P < 0.05), but the ambient temperature had no effect on intermuscular fat width or breast muscle fat content (P > 0.05). There were no differences in jejunal, ileal, or cecal morphology for geese raised at 18, 21, 24, 27, and 30°C (P > 0.05). The duodenal villus height showed a linear decreasing response to increasing ambient temperature, but the ambient temperature had no effect on crypt depth, villus width, muscularis thickness, or villus height/crypt depth of the duodenum (P > 0.05). These results indicate that high ambient temperature decreased growth performance and fat deposition and impaired duodenal morphology of geese. Under our experimental conditions, we recommend that the upper critical ambient temperature for geese from 28 to 49 d of age be 25.19°C.

Effects of ambient temperature on growth performance, blood parameter, and fat deposition of geese from 14 to 28 days of age

An experiment was conducted to investigate the effects of ambient temperature on the growth performance, blood parameter, and fat deposition in geese from 14 to 28 d of age in order to establish their optimal temperature requirements. A total of 150 14-day-old geese were allocated randomly to 5 environmentally controlled chambers with ambient temperature set at 18, 21, 24, 27, and 30°C from 14 to 28 d of age, respectively. As ambient temperature increased from 18 to 30°C, the feed intake decreased linearly (P < 0.05) and was accompanied by linearly or quadratically (P < 0.05) decreasing 28-day-old body weight, weight gain, and feed/gain. The upper critical level of ambient temperature from 14 to 28 d of age for 28-day-old body weight and weight gain were 25.83 and 26.17°C, respectively. There were no differences in plasma biochemical parameters or plasma hormones between geese fed at ambient temperature regimen at 18, 21, 24, 27, and 30°C. The abdominal fat weight and abdominal fat rate decreased linearly (P ≤ 0.05) with higher ambient temperature, but the ambient temperature had no effect on subcutaneous fat thickness or intermuscular fat width. It was concluded that the upper critical temperature of the ambient temperature for geese from 14 to 28 d of age was 26.17°C and high ambient temperature could lead to growth depression.

Centennial Review: History and husbandry recommendations for raising Pekin ducks in research or commercial production

By some accounts, ducks were domesticated between 400 and 10,000 yr ago and have been a growing portion of the poultry industry for decades. Ducks specifically, and waterfowl in general, have unique health, housing, nutrition and welfare concerns compared to their galliform counterparts. Although there have been many research publications in regards to health, nutrition, behavior, and welfare of ducks there have been very few reviews to provide an overview of these numerous studies, and only one text has attempted to review all aspects of the duck industry, from breeders to meat ducks. This review covers incubation, hatching, housing, welfare, nutrition, and euthanasia and highlights the needs for additional research at all levels of duck production. The purpose of this review is to provide guidelines to raise and house ducks for research as specifically related to industry practices.

Early age thermal manipulation on the performance and physiological response of broiler chickens under hot humid tropical climate

Initial brooding temperature is critical for post-hatch growth of broiler chickens. A study was conducted to investigate the early age thermal manipulation (EATM) on the performance and physiological responses broiler chickens under hot humid tropical climate. A total of 260 unsexed day-old Arbor-acre broiler chicks were assigned to five thermal treatments of brooding temperature regimens having 4 replicates of thirteen birds each. The heat treatments were: initial brooding temperature of 35 °C for the first 2 days, and then decreased subsequently, gradually to 22 °C at 21 d of age (CT), initial temperature of 35 °C, sustained for the first 4 days and then decreased gradually (conventionally) (FD), initial temperature of 35 °C for the first 7 days (SD), the birds in CT, but the brooding temperature was raised to 35 °C again for another 3 days from day 7 (SD3), initial brooding temperature of 35 °C for the first 10 days (TD). Data were collected on daily feed intake and weekly body weights. Blood samples were collected from 8 birds per treatment weekly for the determination of plasma uric acid, triglycerides, triiodothyronine (T₃) and creatinine kinase. Data obtained were laid out in a Completely Randomized Design (CRD). Results showed that the final weights of the birds in FD were higher (P < 0.05) than those of the other treatments at the finisher phase. Feed intake of the birds in FD was higher than those of SD3 and TD. FCR of broiler chickens in CT, SD, SD3 and TD was higher than that of FD. The rectal temperature, plasma MDA and blood glucose of the thermally challenged birds in FD was generally better (P < 0.05) than those of the other treatments. It was concluded that EATM can be used to improve performance and also protect broiler chickens from acute heat stress at market age.