Animation doesn't play

I have a shotgun shooting animation, but i can’t get it to play. Here is my Animator component:


Now here is my script:

using UnityEngine;
using System.Collections;

[RequireComponent(typeof(AudioSource))]
public class AimSys : MonoBehaviour
{
    bool Click = false;
    bool target = false;

    public float fireRate = 0.5F;
    private float nextFire = 0.0F;
    public GameObject Flash;
    public Animator anim;


    void Update()
    {
        nextFire -= Time.deltaTime;

        if (Input.GetButton("Fire1") && target && nextFire <= 0)
        {
            anim.SetTrigger("Shoot");
            AudioSource audio = GetComponent<AudioSource>();
            audio.Play();
            Flash.SetActive(true);
            Debug.Log("Target Hit!");
            nextFire = fireRate;
        }
    }

    void OnCollisionEnter(Collision collision)
    {
        {
            if (collision.gameObject.tag == "Enemy")
                target = true;
        }
    }

    void OnCollisionExit(Collision collision)
    {
        {
            if (collision.gameObject.tag == "Enemy")
                target = false;
            Flash.SetActive(false);
        }
    }
}

What i want to do, is when the player click with the left mouse button (fire1), some effects are displayed such as sound effect and image effect, BUT ALSO i want my shooting animation to be played. The problem is that nothing happens! I didn’t get any error, but still my animation just doesn’t play. Could someone help me here?

you need set the value of anim in Start or Awake.

void Start(){
    anim=GetComponent<AudioSource>();
}