Relationships among Puberty,Muscle and Fat,and Liveweight Gain during Mating in Young Female Sheep          下载免费PDF全文

CA Rosales Nieto  MB Ferguson  H Thompson  JR Briegel  CA Macleay  GB Martin  AN Thompson 《Reproduction in domestic animals》2015,50(4):637-642

Greater depths of muscle are associated with better reproductive performance in ewe lambs, but, in adult ewes, reproductive performance also seems to vary with liveweight gain during the mating period. Therefore, in a large field study with Merino ewe lambs, we tested whether the relationships among eye muscle depth (EMD), fat depth (FAT) and reproductive performance depend on liveweight gain during the mating period. We selected lambs with a wide range in phenotypic values for depths of eye muscle (EMD) and fat (FAT) and assigned them to dietary treatments designed to achieve low (LOW, n = 244) or high (HIGH, n = 237) rates of liveweight gain during a 28‐day mating period. The LOW treatment maintained live weight, whereas the HIGH treatment gained 179 ± 3.8 g/day (p < 0.001). From those ewe lambs that attained puberty, first oestrus was detected at live weight 37.8 ± 0.2 kg and age 232 days. The proportion of ewes that attained puberty increased with EMD (p < 0.01). Ewes from the HIGH treatment were more fertile (pregnant ewes per 100 ewes exposed to rams) and had a higher reproductive rate (foetuses in utero per 100 ewes exposed to rams; p < 0.001) than those from the LOW treatment. Fertility and reproductive rate were positively correlated with weight gain during mating as well as live weight at the start of mating, FAT and EMD (p < 0.05 to <0.001). We conclude that faster growth, due to either extra nutrition during mating or higher phenotypic potential for fat and muscle, will increase reproductive performance in ewe lambs mated at 8 months of age.  相似文献   

High dietary concentrations of biotin did not prevent foot pad dermatitis in growing turkeys and external scores were poor indicators of histopathological lesions     

Mayne RK  Else RW  Hocking PM 《British poultry science》2007,48(3):291-298

1. A randomised block experiment was conducted to determine the effects of increasing dietary biotin supplementation (0, 200, 800 and 1600 microg/kg) on macroscopic and histological changes associated with the development of foot pad dermatitis (FPD) in growing turkeys. 2. Each treatment was replicated in 4 pens containing 36 birds at the start of the experiment. The birds were weighed and external foot pads were scored at 2-week intervals from 2 to 14 weeks of age. A blood sample was obtained at the same ages from two birds in each pen and tissue from one foot pad was processed for histological examination. Liver samples were obtained for determination of fat content. 3. Increasing dietary biotin supplementation was associated with higher initial plasma concentrations of biotin but there was no effect on external scores or histopathology of foot pad lesions. FPD increased rapidly from 2 to 6 weeks and remained similar thereafter. There was no effect of dietary biotin on liver fat content. 4. The correlations between external foot pad scores at different ages were all less than 0.4. The correlation between external and histopathological scores was 0.56 and the respective correlations with body weight were 0.52 and 0.65. There were no differences between the body weights of birds with different external scores but high histopathological scores were associated with lower body weights. 5. It was concluded that current recommendations for biotin in wheat-soy rations for growing turkeys are adequate for normal growth and development and that higher supplements of biotin in these experimental conditions did not prevent the occurrence of FPD.  相似文献   

Implications of nitrogen fertilizer applications and extended grazing for the N economy of grassland     

Laidlaw  Watson  & Mayne 《Grass and Forage Science》2000,55(1):37-46

The response of swards which have been previously grazed to N fertilizer applied in early February was studied in two experiments in Northern Ireland. The effect of N fertilizer applied at a range of dates in autumn and spring on swards for out-of-season utilization was studied in a further experiment. Deep soil coring was also undertaken, subsequent to grazing with dairy cows, in grazed and protected areas in November and March to investigate the effect of out-of-season grazing on soil mineral N levels.
Dry-matter (DM) yield response to early spring N application in previously grazed swards was low, with no effect on DM yield in February or March. Progressively delaying N application (and commencement of herbage accumulation) in autumn from 8 September until 18 October reduced herbage availability in late autumn and early spring but increased leaf lamina content. The greater the amount of herbage accumulated to 1 December, the lower the tiller density in the following April.
N fertilizer had a greater impact on soil mineral N in spring than in late autumn/early winter, suggesting that fertilizer N was more prone to loss in the latter. Soil mineral N was not significantly affected by out-of-season grazing.
It is concluded that in well-fertilized, previously grazed swards response to N for out-of-season herbage is low and the probability for N loss is increased. Herbage quality will decline and the sward may be damaged if about 2 t DM ha⁻¹ or more of harvestable herbage accumulates for use in winter or in early spring.  相似文献   

Effects of High-Voltage Cathode-Ray Irradiation on Cottonseed     

Lambou MG  Mayne RY  Proctor BE  Goldblith SA 《Science (New York, N.Y.)》1952,115(2984):269-271

  相似文献   

Raymond Greene: Physician, Mountaineer, and Raconteur     

George W. Rodway PhD  Victoria Gibbs BSc  Jeremy S. Windsor MB ChB 《The Forestry Chronicle》2011,22(3):270-276

  相似文献   

Stem Cell–based Therapies for Bone Repair     

Peter I. Milner BVetMed  PhD  CertES  MRCVS  Peter D. Clegg MA  Vet MB  PhD  Matthew C. Stewart BVSc  MVetClinStud  PhD 《Veterinary Clinics of North America: Equine Practice》2011,27(2):299-314

  相似文献   

IDENTIFICATION OF ARACHNOID CYSTS IN THE QUADRIGEMINAL CISTERN USING ULTRASONOGRAPHY     

Miyoko  Saito  DVM  Natasha J.  Olby  VET MB  PhD  Kathy  Spaulding  DVM 《Veterinary radiology & ultrasound》2001,42(5):435-439

The ultrasonographic findings in three small breed dogs with intracranial arachnoid cysts are described. Ultrasound images were obtained via the foramen magnum, temporal window and persistent bregmatic fontanelle (when possible). In transverse, dorsal and sagittal transcranial ultrasound images there was marked dilation of the lateral ventricles and a well-defined, oval to triangular-shaped anechoic area between the caudal aspect of the occipital lobes, dorsal to the midbrain, and rostral to the cerebellum. These findings were consistent with a diagnosis of concurrent hydrocephalus and an arachnoid cyst within the quadrigeminal cistern.  相似文献   

Endogenous Benzodiazepine Activity in the Peripheral and Portal Blood of Dogs With Congenital Portosystemic Shunts     

LILLIAN R. ARONSON VMD    REYNALDO C. GACAD MD    KRISTINE KAMINSKY-RUSS MS    CLARE R. GREGORY DVM  Dipiomate ACVS  KEVIN D. MULLEN MB  FRCPI 《Veterinary surgery : VS》1997,26(3):189-194

Objective- The purpose of this study was to determine whether an endogenous benzodiazepine receptor ligand (EBZ) was present in the arterial and portal blood of dogs with congenital portosystemic shunts (CPSS).
Study Design- The presence or absence of an EBZ was determined by the collection of systemic and portal blood from dogs with CPSS.
Animals- Fifteen client-owned dogs with a confirmed CPSS. All dogs had historical signs compatible with hepatic encephalopathy. Eight healthy dogs were used as controls.
Methods- In all dogs, systemic blood samples were collected after they were anesthetized. Portal blood samples were collected intraoperatively. EBZ was measured by radioreceptor assay.
Results- In 10 of 15 dogs, the portal blood concentration of EBZ was significantly elevated compared with normal dogs (mean, 13.2 ±18.55 ng/mL). Five dogs had elevated systemic blood EBZ levels (mean, 8.2 ±16.08 ng/mL). Eleven of 15 dogs had a higher portal than systemic blood concentration of EBZ. In contrast, control dogs had extremely low EBZ concentrations detected in their portal blood (mean, 0.16 ±0.3 ng/mL) and systemic blood (0 ng/mL). The mean portal and systemic blood concentrations in dogs with CPSS were significantly greater than in control dogs ( P <.05).
Conclusions- Elevated blood levels of EBZ were found in dogs with CPSS. The portosystemic gradient noted in 11 dogs suggests the gastrointestinal tract as a possible source for the endogenous ligand.
Clinical Relevance- Generalized motor seizures have been reported in dogs after surgical correction of CPSS. If the presence of a CPSS results in stimulation of brain receptors for benzodiazepines, post-CPSS ligation seizures may result from a withdrawal of EBZ after ligation of the portosystemic shunt.  相似文献   

TRUE DIAPHRAGMATIC HERNIA IN A CAT     

Andra K.  Voges  DVM  Scott  Bertrand  DVM  Richard C.  Hill  MA Vet MB  PhD  Lisa  Neuwirth  DVM  MS  Michael  Schaer  DVM 《Veterinary radiology & ultrasound》1997,38(2):116-119

A report of a cat with a true diaphragmatic hernia in which only falciform fat had herniated is pressented. The lession was misinterpreted as a pulmonary mass. Additional radiographic studies which may have been of diagnostic benefit are briefly discussed.  相似文献   

Normal and abnormal sex, chromosomes and H-Y antigen     

C.R.E. Hainan MA VET. MB  PhD  FRCVS 《Journal of Equine Veterinary Science》1985,5(1):38-39

  相似文献