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2. Forty young hens and 40 older hens were caged individually. Each group of hens was randomly allotted to four treatments for 21 days: either a control, an oestradiol group, a high energy-low protein diet (HELPD) group or a HELPD + oestradiol group. Blood levels of oestradiol, triglyceride (TG), cholesterol (CHOL), high density lipoprotein-cholesterol (HDL-C) and low-density lipoprotein-cholesterol (LDL-C), liver total lipids, hepatic haemorrhagic scores and productive performance were assessed.
3. In older hens, β-oestradiol increased (P < 0.05) liver total lipids, hepatic haemorrhagic scores and the incidence of FLHS but reduced (P < 0.05) productive performance; however, such changes were not observed in young hens.
4. In two groups of hens, serum TG, CHOL and HDL-C levels were increased (P < 0.001) by β-oestradiol. Hens with FLHS had higher serum TG, CHOL and HDL-C (P < 0.001) than non-FLHS birds in the older layer group of hens.
5. An interaction (β-oestradiol × HELPD) (P < 0.05) for LDL-C levels was observed in both groups of hens. In young hens, β-oestradiol induced a decrease (P = 0.004) in serum LDL-C levels but the effect was attenuated by HELPD. In older hens, HELPD caused an increase (P = 0.02) in serum LDL-C although the effect depended on the presence of β-oestradiol.
6. In conclusion, older layers were more susceptible to FLHS than young layers after oestradiol treatment. Blood TG, CHOL and HDL-C rather than LDL-C levels can be used as a prediction tool for the overall susceptibility to FLHS in older rather than young layers. There were interactions between oestradiol and HELPD on blood LDL-C levels in laying hens. 相似文献
Pet abuse has been identified as a potential risk factor for DV, and DV perpetrators may harm or kill a pet to exert physical, psychological or emotional control over an intimate partner. Given that victims of DV often seek veterinary aid for their pets, veterinarians may act as frontline professionals in the recognition of the link between PA and DV. Veterinarians must assess individual cases for diagnostic indicators of non-accidental injury and consider demographic factors to identify suspected PA and DV. Despite existing legal and ethical obligations of the veterinarian relating to suspected PA and victims of DV, veterinarians have uncertainty and unpreparedness in addressing PA and DV in a clinical context. Many factors may contribute to the lack of veterinary intervention in suspected cases of PA and DV including concern for animal welfare, confusion about the reporting process and uncertainty in differentiating accidental versus non-accidental injuries in pets. Specific published guidelines regarding the recognition and reporting of PA and DV in the veterinary clinical context are required. Limited published evidence exists examining the implementation and success of veterinary training regarding the relationship between DV and PA. Ultimately, veterinary student education is needed to prepare veterinarians for their response to PA and DV in practice. Further research is required to examine the effects of the delivery of content regarding the link between PA and DV in the veterinary curriculum on veterinary student knowledge and attitudes. 相似文献