Effect of cold stress on performance and immune responses of Bedouin and white leghorn hens     

M. Spinu  A. A. Degen 《British poultry science》1993,34(1):177-185

1. Bedouin chickens are kept in deserts mainly for eggs and are well adapted to arid conditions. However, deserts are also characterised by relatively cold winter nights. As a consequence of cold stress there is an involution of lymphoid organs and a depression of immunological function. We compared the performance and immunological responses of Bedouin and White Leghorn hens kept in outdoor pens in the Negev Desert during the winter.

2. Initial mean body mass was similar for the two breeds: 1525 g for Bedouin hens and 1542 g for White Leghorn hens. White Leghorns lost 7–74 g/d, compared with 0.60 g/d for Bedouin hens and produced 0.36 eggs/d, compared with 0.54 eggs/day for Bedouin hens.

3. The heterophil/lymphocyte ratio for Bedouin hens was 0.28, which was lower than the 0.44 for White Leghorn hens. Phagocytic index was higher in Bedouin hens than in White Leghorns. Furthermore, wattle index measured 24, 48 and 72 h after PHA injections and anti‐SRBC antibody titres determined 10 d after challenge were also higher in Bedouin hens than in White Leghorns.

4. We concluded that the Bedouin hens were less stressed by the cold than were the White Leghorn hens.  相似文献   

Utilisation of raw jackbean (Canavalia ensiformis) and jackbean fractions in diets for broiler chicks     

A. D. Ologhobo  D. F. Apata  A. Oyejide 《British poultry science》1993,34(2):323-337

1. An experiment was conducted to examine the effectiveness of some extraction procedures at eliminating the antinutritional properties of jackbean to the broiler chicken. The most pronounced effects were observed in the base‐ and acid‐soluble protein fractions (BSP and ASP) which contained the bulk of the antinutritional factors.

2. The growth of chickens on all diets were significantly (P<0.05) reduced.

3. Examining the weights of broiler organs as a proportion of body weight showed a significant (P<0.05) decrease in the weight of the liver and an increase in the weights of the kidney, brain and pancreas.

4. Serum urea concentrations were elevated (P<0.05) in all groups receiving base‐soluble protein (BSP), acid‐soluble protein (ASP), defatted jackbean (DJB) and raw jackbean (RJB) diets. Enzyme activities were similarly elevated (P<0.01), but serum protein and albumin concentrations were depressed while uric acid was not influenced by dietary treatment.

5. Histopathological examination revealed several pathological lesions in organs of chicks fed on the BSP, ASP, DJB and RJB diets. The presence of lesions was less marked in the organs of chickens fed on diets containing base‐insoluble residue (BIR), acid‐insoluble residue (AIR) and ethanol‐extracted meal (EEM), while those given the aqueous heated jackbean diet did not show any pathological effects.  相似文献   

Effect of warm drinking water on the performance and immunological responses of broiler breeder hens raised at low air temperatures     

M. Spinu  A. A. Degen  A. Rosenstrauch 《British poultry science》1993,34(2):361-366

1. The effect of warmed drinking water on the performance and immunological responses of broiler breeder hens maintained at low air temperatures (5.0° to 12.9°C) was tested. From 22 weeks of age hens (mean body mass = 2.4 kg) were offered either warm water (27.7°C; WARM; n=24) or tap water (12.7°C; CONR; n=24) twice daily for a total time of 2.5 h or tap water ad libitum (CONA; n = 16). Food was restricted for all hens.

2. Daily water intake in the WARM hens (103 ml/kg) was similar to that of the CONR (93 ml/kg) and CONA hens (106 ml/kg).

3. There were no significant differences in either body mass change or egg production among treatment groups.

4. There was no difference among groups in heterophil/lymphocyte ratios. Similarly, there was no difference among groups in either phagocytic activity or wattle index after phytohaemagglutinin (PHA) injection. Total and IgG antibody titres to SRBC tended to be highest in the WARM hens and these titres were significantly higher than in CONR hens 14 d after challenge.  相似文献   

Associations between body weight and rectal temperature in turkey poults     

P. E. Waibel  M. G. Macleod 《British poultry science》1993,34(2):417-423

1. Associations between body weight and rectal temperature were observed in female turkeys.

2. Turkeys with lower weights between 13 and 30 d of age tended to have higher temperatures.

3. Turkeys with lower weights at 7 d exhibited depressed body temperatures.

4. Higher or lower body temperatures may be associated with poorer performance depending on the time of appearance.  相似文献   

Comparison of the rates of proliferation of adipocyte precursor cells derived from two lines of chicken which differ in their rates of adipose tissue development     

L. E. Donnelly  A. Cryer  S. C. Butterwith 《British poultry science》1993,34(1):187-193

1. Putative adipocyte precursor cells were isolated from the white adipose tissue of young broiler and layer chickens and cultured in vitro.

2. The cells from both sources were shown to have the characteristics of adipocyte precursor cells. On reaching confluence, lipoprotein lipase activity was induced and the cells from both strains accumulated large amounts of lipid in the presence of chicken serum.

3. Measurement of cell number over time in culture and calculation of cell doubling times showed that cells from broilers proliferated at a faster rate than those derived from layer‐strain chickens. This was the case whether primary or secondary cell cultures were used. Primary cultures of broiler cells had a doubling time of 22 h versus 39 h for layer cells.

4. The contribution of such a difference in proliferative rate to the differential rate of adipose tissue growth between broiler and layer strains observed in vivo is discussed.  相似文献   

Feeding behaviour in chickens given diets containing medium chain triglyceride     

M. Furuse  R. T. Mabayo  Y. H. Choi  D. M. Denbow  J. Okumura 《British poultry science》1993,34(1):211-217

1. The effect of dietary medium chain triglyceride (MCT) on short‐term food intake was compared with the effect of long chain triglyceride (LCT) in chickens. Maize oil was used as the LCT while glyceryl tricaprylate (C 8) and glyceryl tricaprate (C 10) were used as MCT. Cumulative food intake was determined during the 6 h after the start of feeding.

2. Chicks were given diets containing 200 g C 8/kg diet, 200 g C 10/kg diet or 200 g LCT/kg diet in experiment 1. As early as 30 min after feeding, cumulative food intake in both MCT‐supplemented diets decreased significantly compared with the diet containing LCT.

3. To determine if endogenous cholecystokinin (CCK) was responsible for the decrease in food intake caused by MCT, birds were injected with the CCK‐A receptor antagonist devazepide (DVZ, 1 mg/kg BW) before diet presentation. DVZ had no effect on food intake with either LCT‐ or MCT‐supplemented diets.

4. In experiment 3, chicks were given a choice between either diets containing LCT and C 8, LCT and C 10, or C 8 and C 10 to confirm whether or not the palatability of the diets was influenced by the dietary fat sources. There was no difference in food intake between C 8 and C 10‐supplemented diets. However, chicks preferred the LCT‐supplemented diet compared with either of the diets containing MCT.  相似文献   

Nesting and dust bathing by hens in cages: Matching and mis‐matching between behaviour and environment     

S. F. Smith  M. C. Appleby  B. O. Hughes 《British poultry science》1993,34(1):21-33

1. Medium hybrid hens were housed as groups of 4 at 18 weeks of age in cages of 4 different types: control battery cages allowing 675 cm2/bird; similar cages with a rear‐mounted dust bath, 290×345×240 mm, containing sand (D); cages with a rear‐mounted nest box of the same size, containing wood shavings (N); cages with both (DN). In half the experimental cages access to nests was restricted to the morning and access to baths was restricted to the afternoon, by automatic sliding doors.

2. During the first 24 weeks of lay about 95% of eggs were laid in nest boxes in treatments N and DN. Slightly fewer were laid in boxes where doors were present. Over 90% were laid in dust baths in D cages without doors and 67% with doors, which birds learned to open. Prelaying behaviour was least disturbed in nest boxes, most disturbed on the floor and intermediate in dust baths.

3. Fully developed dust bathing occurred in D and DN as bouts lasting 5 to 10 minutes; its incidence, surprisingly, was greater when doors were present and greater still when nest boxes were present, even though it was not performed in them. It was also performed by some hens in nest boxes in N (without doors). In N with doors and in control cages, dust bathing occurred on the bare floor in truncated form, as serial bouts each lasting only about 10 s. This truncated dust bathing was also occasionally observed in D and DN.

4. Plumage, foot and claw damage were less in hens from modified cages than from controls. Egg production was very good in all treatments but more eggs from control cages were downgraded because they were dirty or cracked.

5. When a choice was available birds generally partitioned their behaviour appropriately between nest box and dust bath. In N and DN virtually all prelaying and nesting behaviour took place in the nest boxes. Matching between dust bathing and the environment was less close; the reasons for its relatively low incidence and occurrence in truncated form outside dust baths remain to be established.  相似文献   

Evaluation of a chromogenic antithrombin III assay using a fixed band spectrophotometer     

Andreasen CB  Lovelady S 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1993,22(2):42-44

  相似文献   

What Is Your Diagnosis?     

Andreasen CB 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1993,22(3):67-69

  相似文献   

The pharmacokinetics of thiamphenicol in lactating cows   总被引：2，自引：0，他引：2  

N. Mestorino  M. F. Landoni  M. Alt  J. O. Errecalde 《Veterinary research communications》1993,17(4):295-303

The pharmacokinetics of thiamphenicol were studied after intravenous and intramuscular administration of 25 mg/kg body weight in lactating cows. Distribution (t _1/2) and elimination (t _1/2) half-lives of 6.10±1.39 min and 1.60±0.30 h, respectively, were obtained after intravenous administration. The body clearance was 3.9±0.077 ml/kg per min and the apparent volume of distribution was 1220.79±256.67 ml/kg. The rate at which thiamphenicol appeared in the milk, as indicated by the penetration half-life (t _1/2P) (serum to quarters), was found to be 36.89±11.14 min. The equivalent elimination half-life (t _1/2E) (quarters to serum) from the milk was 3.62±1.06 h and the peak thiamphenicol concentration in the milk was 23.09±3.42 µg/ml at 2.5±0.32 h.After intramuscular injection, the elimination half-life was 2.2±0.40 h, the absorption half-life was 4.02±1.72 min and the peak concentration in the serum was 30.90±5.24 µg/ml at 23±8.4 min. The bioavailability after intramuscular administration approached 100%. The penetration half-life was 50.59±6.87 min, the elimination half-life was 5.91±4.97 h and the mean peak concentration in the milk was 17.37±2.20 µg/ml at 3.4±0.22 h.Abbreviations AUC area under the concentration-time curve - CAP chloramphenicol - C _max peak concentration - IM intramuscular - IV intravenous - TAP thiamphenicol - t _1/2 distribution half-life - t _1/2 elimination half-life - V _c volume of central compartment - V _d volume of distribution  相似文献