3Diesel G, Brodhelt D, Laurence C, Survey of veterinary practice policies and opinions on neutering dogs [J]. Veterinary Record, 2010, 166: 455-458.
4Thrusfield M. The dilemma of when to neuter[J].The Veterinary Journal, 2011, 187: 12-13.
5Okkens A C, Kooistra H S, Nickel R F. Comparison of longterm effects of ovariectomy vs ovariohisterectomy in bitches [J]. J Reprod Ferd Suppl, 1997, 51: 227-331.
6Robertson I D. The association of exercise, diet and other factors with owner-perceived obesity in privately owned dogs from metropolitan Perth, W A [J]. Preventive Veterinary Medicine, 2003, 58: 75-83.
7Kanchuk M L, Backus R C, Calvert C C, etal. Neutering induces changes in food intake, body weight, plasma insulin, and leptin concentrations in normal and lipoprotein lipase-deficient male cats [J]. Journal of Nutrtion, 2002, 132: 1730S- 1732S.
8Kienzle E, Edtstadtler-Pietsch G, Rudnick R. Retrospective study on the energy requirements of adult colony cats [J].Journal of Nutrition, 2006, 136: 1973S-1975S.
9Salmeri K R, Bloomberg M S, Scruggs S L, etal. Gonadectomy in immature dogs: effects on skeletal, physical, and behavioral development [J]. Journal of the American Veterinary Medical Association, 1991, 198(7): 1193-1203.
10Toll P W, Yamka R M, Schoenherr W D, et al. Obesity [M]// Hand M S, Thatcher C D, Remillard R L, etal. Small Animal Clinical Nutrition. Kansas: Mark Morris Institute, 2010: 501-542.
