public void Add_Fail()
        {
            var service = GetMockedAnimalService();

            service.Setup(x => x.Add(It.IsAny <AnimalContract>())).Returns(new OperationResult(false, "Fail"));
            var controller = new AnimalsController(service.Object);

            var result = (OperationResult)controller.Add(new AnimalContract()).Data;

            Assert.IsFalse(result.Success);
            Assert.IsNotEmpty(result.Message);
        }