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1.
1. The impact of daylength on productivity in male and female broilers of two genotypes was studied in two replicated experiments. In each experiment, four lighting programs (14 L:10 D (14 L), 17 L:7 D (17 L), 20 L:4 D (20 L) and 23 L:1 D (23 L)) were used to study the relationships between productivity and daylength in two genotypes and both genders. 2. General Linear Model analysis was used to test for differences in daylength, genotype, gender and their interactions, and regression analysis to define relationships between productivity and daylength in experiment one and daylength differences in experiment two. 3. In experiment one, body weights at d 32 ( P?=?0·002) and d 39 ( P?=?0·011) were related in a quadratic fashion to daylength, with the heaviest birds raised under 20 L. The growth curve at d 49 was similar in shape, and body weights under both 17 L and 20 L were significantly higher than under 14 L and 23 L ( P? 4. Feed consumption was highest to d 39 or d 49 under 20 L, and birds under 23 L ate as much (d 39) or less feed (d 49) than under 17 L. 5. Gain-to-feed efficiency (FCR) responded in a quadratic fashion, with maximum efficiency observed under the shortest daylength. 6. Mortality increased linearly with daylength for all time periods in both experiments. 相似文献
2.
1?Dietary phytic acid (PA) reduces the apparent digestion and of dietary nutrients, increases the excretion of endogenous amino acids and minerals and reduces the concentration of blood glucose. 2?An experiment was conducted to examine the effect of phytic acid on the absorption capacity of the intestine in broiler chicken, using a D-xylose absorption test. 3?Three groups of ten 26-d-old apparently healthy broiler cockerels (Ross 308) were dosed with D-xylose solution (500 mg/kg BW, Group 1) or D-xylose solution + PA (330 or 660 mg/5 ml/bird, in groups 2 and 3), respectively. The plasma concentration of D-xylose was measured at 40-min intervals after ingestion of test materials, for a total of 160 min. 4?There was a quadratic correlation between the concentration of plasma D-xylose and time in all experimental groups (P < 0?001, R 2= 0?78, 0?80 and 0?81 for groups 1–3, respectively). Ingestion of PA at 660 mg reduced the concentration of plasma D-xylose by 21?6 and 10?5% at 40 and 80 min after ingestion of the test material, indicating a lower absorption of this sugar. 5?It was concluded that dietary phytates might affect the productive performance of chicken, at least partly, by disturbing the transport mechanisms involved in the absorption of nutrients. 相似文献
3.
Extract D onald R ossdied at Palmerston North on 14 October, 1959, after many months of illness, borne with great fortitude and courage. 相似文献
4.
The aim of the study was to determine the effects of dietary supplementation with sodium nitroprusside (SNP), a nitric oxide (NO) exogenous donor, and NG-nitro-l-arginine methyl ester (l-NAME), a NO inhibitor, on growth performance, some biochemical parameters and ovarian primordial and primary follicles of quail. A total of 480 Japanese quail (Coturnix coturnix japonica), one-day-old, including both males and females, were randomly allocated into one control group and 4 treatment groups each consisting of 96 birds. The control group was fed on the basal diet, whereas the experimental groups were fed on the basal diet supplemented with 50 mg SNP/kg, 200 mg SNP/kg, 50 mg l-NAME/kg or 200 mg l-NAME/kg. In the group receiving 200 mg SNP/kg, BW was lower on d 28 and d 42 compared to the control group and body weight gain (BWG) was lower between weeks 2 and 4 compared to the control group. In the same group, BWG and feed consumption were lower compared with the control group. In the group receiving 200 mg l-NAME/kg, BW on d 42 and BWG were lower, whereas feed consumption and FCR was higher than in the control group. In the groups supplemented with SNP at 50 and 200 mg/kg, serum total protein and albumin were higher than the control group; however, serum lipid profile, and liver and kidney enzymes were not affected by supplementation with SNP or l-NAME. The numbers of ovarian primordial and primary follicles were greater in the group fed on the diet supplemented with 200 mg SNP/kg compared with the control group. Supplementation at 200 mg l-NAME/kg diet reduced the number of primary follicles compared to the controls, whereas the diameter of primordial and primary follicles increased. In conclusion, supplementation with SNP and l-NAME depressed quail growth. Furthermore, the increase in NO following dietary supplementation with the NO-donor SNP delayed the growth process from primordial to primary and primary to secondary follicle transition in quail.
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5.
Abstract Extract A lthough the opinion has been expressed (Andrews, 1971 Andrews, E. D. 1971. Cobalt deficiency in sheep and cattle. N.Z. Dept. Agric. Bull., : 180–180. [Google Scholar]) that cobalt deficiency among cattle has virtually disappeared in New Zealand and that specimens for laboratory examination are rarely required, 15 to 20% of the liver samples submitted by veterinarians to the Animal Health Reference Laboratory for vitamin B 12 assay are from cattle. Diagnostic criteria for cobalt (vitamin B 12) deficiency cy have long been established for sheep but not for cattle In view of the continuing requests for vitamin B 12 analyses on bovine livers, it was desirable to establish normal values for clinically normal cattle so that results of routine diagnostic analyses could be more readily interpreted. 相似文献
6.
The aim of the current study was to investigate the interaction of the nitric oxide and cannabinoidergic systems on feeding behaviour in neonatal chicken. A total of 6 experiments were designed to evaluate the interaction between cannabinoidergic and nitrergic systems on food intake in 3-h food-deprived (FD3) neonatal chickens. In Experiment 1, chickens received intracerebroventricular (ICV) injections of saline, 2-arachidonoylglycerol (2-AG) (a CB1 receptor agonist, 2 µg), l-arginine (nitric oxide precursor, 200 nmol) and co-administration of 2-AG + l-arginine. In Experiment 2, ICV injection of saline, 2-AG (2 µg), l-NAME (a nitric oxide synthesis inhibitor, 100 nmol) and their combination (2-AG + l-NAME) were applied to the birds. In Experiment 3, injections were saline, CB65 (a CB2 receptor agonist, 1.25 µg), l-arginine (200 nmol) and CB65 + l-arginine. In Experiment 4, birds received ICV injection of saline, CB65 (1.25 µg), l-NAME (100 nmol) and CB65 + l-NAME. In Experiment 5, chickens were ICV injected with saline, l-arginine (800 nmol), SR141716A (a selective CB1 receptor antagonist, 6.25 µg) and l-arginine + SR141716A. In Experiment 6, birds were injected with saline, l-arginine (800 nmol), AM630 (a selective CB2 receptor antagonist, 5 µg) and l-arginine + AM630. Cumulative food intake was recorded until 2-h post injection. ICV injection of CB1 and CB2 receptor agonists increased food intake. Co-injection of 2-AG + l-NAME increased the hyperphagic effects of CB1 receptors. CB2 receptor-induced food intake was not affected by co-administration of CB65 + l-NAME. l-Arginine decreased food intake and this effect was amplified by co-injection of l-arginine + SR141716A. However; CB2 receptor antagonists had no effect on l-arginine-induced hypophagia. The results suggest that there is an interaction between endogenous nitric oxide and the cannabinoidergic system on feeding behaviour which is mediated via CB1 receptors in the neonatal chicken.
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7.
1. The effects of Aspergillus oryzae- and Bacillus subtilis-based direct-fed microbials (DFM) were investigated on the performance, ileal nutrient transport and intestinal integrity of broiler chickens, raised under experimental conditions, with increased intestinal microbial challenge. 2. The first study was a 3 × 2 factorial experiment, with 3 dietary treatments (control (CON), CON + DFM and CON + antibiotic growth promoter) with and without challenge. Chicks were fed experimental diets from 1 to 28 d, while the challenge was provided by vaccinating with 10 times the normal dose of commercial coccidial vaccine on d 9. In a second experiment, two groups of 1 d-old broilers, housed on built-up litter (uncleaned from two previous flocks), were fed the same CON and CON + DFM diets from 1 to 21 d. 3. The challenge in the first experiment reduced performance, but no differences were observed among dietary treatments from 8 to 28 d. The challenge reduced the ileal epithelial flux for D-glucose, L-lysine, DL-methionine and phosphorus on d 21. Epithelial flux for D-glucose, L-lysine and DL-methionine were increased by DFM. Ileal trans-epithelial electrical resistance (TER) was increased in challenged broilers fed DFM, although this was not observed in unchallenged birds as indicated by a significant interaction. 4. Ileal mucin mRNA expression and colon TER were increased, and colon endotoxin permeability was reduced by DFM on d 21 in the second experiment. 5. It was concluded that the addition of DFM in the diet improved the intestinal integrity of broiler chickens raised under experimental conditions designed to provide increased intestinal microbial challenge. 相似文献
8.
Extract F rom references made in ancient books of the Hindus and also on terracottas and carvings extending to the Harrapan period, it would appear that a veterinary profession existed in India from at least 2000 b.c. 相似文献
9.
1. This experiment was carried out to evaluate the productive and physiological consequences of a slight but long term food restriction of male broiler chickens from 2 commercial strains. 2. Cobb-500 and Ross chickens were submitted to a 20% food restriction from 8 to 21 d of age. Strain, food programme and their interactive effects were analysed in terms of consequences upon performance, mortality, incidence of sudden death syndrome (SDS) and ascites syndrome (AS), index of right cardiac hypertrophy and plasma concentrations of hormones related to metabolism and growth (T 3, T 4, T 3:T 4 ratio, IGF-I and GH). 3. Although some catch-up growth was observed by refeeding previously restricted birds after 22 d of rearing, food restriction decreased ( P ≤ 0.05) body weight at market age (42 d) irrespective of the strain, but improved ( P ≤ 0.05) food conversion. 4. The incidence of mortality was not high in non-restricted birds but SDS and AS caused more than 50% of deaths. Hypertrophic cardiac index was observed in chickens of both strains after 4 weeks of age and was higher in ad libitum fed birds. 5. During the period of food restriction, plasma T 3 and IGF-I concentrations decreased whereas plasma T 4 and GH concentrations increased compared to those of the age-matched ad libitum fed counterparts. During the subsequent ad libitum feeding period, few differences in circulating hormone concentrations were observed, except for the higher mean GH litres in previously food-restricted chickens at 35 d of age. 6. These results indicate that even a non-severe food restriction negatively affects body weight of 42-d-old male broilers but these are benefits with improved food efficiency and diminished mortality from metabolic disturbances. The hormone results suggest that the degree of food restriction applied was not severe because there was a very fast adaptive response with small and transient alterations in T 3, T 4 and GH plasma concentrations during the period of compensatory growth. 相似文献
10.
Abstract Extract E ach year in N ew Z ealand, many rams are palpated for lesions of the epididymes and testes. Although regarded initially as a method of detecting infertile rams (Crawford and James, 1950 Biberstein, E. L. and McGowan, B. 1958. Cornell Vet., 48: 31–31. [Google Scholar]), the technique is now regarded primarily as a method of detecting infection with the organism for which Buddie ( 1956 Buddle, M. B. 1956. J.Hyg., 54: 351–351. [Google Scholar]) proposed the name Brucella ovis. 相似文献
11.
S tanley F letcher was a well-known and respected general practitioner in Masterton for many years. He will be remembered as a valiant old-timer, kindly and conscientious, humane and ethical. 相似文献
12.
Extract T here can be no doubt that severe depression of animal production occurs as the result of worm infestation in sheep and cattle. 相似文献
13.
1. Simultaneous changes of cloacal gland area (CGA) and plasma luteinising hormone (LH), follicle stimulating hormone (FSH), testosterone (T), prolactin (PRL), thyroxine (T 4) and triiodothyronine (T 3) during photo-induced testicular growth and regression were measured in commercially bred Japanese quail from a heavy body weight line. 2. Somatically mature male Japanese quail were transferred from short days (light:dark 8L:16D) at 10°C, to long days (16L:8D) at 20°C; and sexually mature male Japanese quail were transferred from long to short days. All variables were measured at transfer and every 5?d thereafter for 35?d. 3. Transfer from short to long days caused significant increases in LH, FSH, T and testis weight (TW) after 5?d, and in CGA after 10?d. T3 decreased after 5?d, whereas T4 increased significantly after 25 long days and PRL did not undergo any consistent change. The testicular growth rate was k?=?0·1146. 4. Transferring quail from long to short days caused significant decreases in LH and FSH after 5?d, and decreases in T, TW and CGA after 10?d. T4 decreased after 5?d whilst T3 increased significantly by day 15. PRL decreased significantly after 10?d then rose before declining again. The testicular regression rate was k?=?0·0582. 5. The rates of photo-induced testicular development and regression in a strain of large Japanese quail did not differ from rates reported for other strains of quail. CGA was a better indicator of TW than plasma T concentrations during growth and regression. The role of PRL in photo-induced reproductive cycles in male Japanese quail remains to be determined. 6. The photoperiod-induced changes in gonad size and hormone concentrations, together provide valuable information that can be used in future studies of the endocrinology and neuroendocrinology of photoperiodism in birds. 相似文献
14.
Extract W ith the trend towards heavier stocking of sheep and cattle on New Zealand hill country, considerable stress is being placed on beef calves during the winter months following weaning. 相似文献
15.
Abstract Extract F ollowing the use of pregnancy diagnosis as an aid to farming beef cattle herds as described by McFarlane (1955) McFarlane, D. 1955. Massey Agricultural College Sheepfarming Annual, 1955: 66–66. [Google Scholar], it became apparent that many cows already inoculated with Strain 19 were aborting after pregnancy diagnosis. These abortions occurred only on a small proportion of the properties, so that it was unreasonable to assume that they were in any way associated with the physical interference at pregnancy diagnosis. 相似文献
16.
Extract S ince 1955, a specific entity characterized by siderosis and osteoporosis has been recognized in beef cattle at slaughter from one property. This paperdescribes the preliminary observations. 相似文献
17.
Extract I n the Gisborne-East Coast District, the cattle tick ( Haemaphysalis bispinosa) occurs in fairly well defined areas, most of them with a northerly aspect and with favourable cover such as rushes and low manuka scrub. 相似文献
18.
Extract D uring the course of an investigation into perinatal calf deaths in the Gisborne area during the spring of 1958, seven cases of micrencephaly were recorded. 相似文献
19.
Extract T he following is a method of bleeding cattle from the median ventral coccygeal artery or vein as demonstrated at a refresher course for Government veterinarians and livestock instructors held at Wallaceville Animal Research Station in 1961. 相似文献
20.
Extract R ifamastene § § Trademark of Gruppo Lepetit S.P.A., Milan, Italy. is a water-miscible formulation of the new antibiotic rifamycin SV designed for use as an udder infusion for the treatment of bovine mastitis. 相似文献
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