Animals of Farm despawn

My problem is that i have a Server with a Big Farm (I also use KeepChunks Plugin) but i think because of some PaperMC Option the TickRate gets slower if you go away or the Animals even despawn.
Wich of those Settings down there do i need to change so that stops happening?
I use PaperMC 14.4 and the Settings down below are from the Standard paper.yml file.

verbose: false
config-version: 20
settings:
  save-player-data: true
  region-file-cache-size: 256
  incoming-packet-spam-threshold: 300
  use-alternative-luck-formula: false
  use-versioned-world: false
  suggest-player-names-when-null-tab-completions: true
  load-permissions-yml-before-plugins: true
  bungee-online-mode: true
  enable-player-collisions: true
  save-empty-scoreboard-teams: false
  async-chunks:
enable: true
load-threads: -1
  watchdog:
early-warning-every: 5000
early-warning-delay: 10000
  spam-limiter:
tab-spam-increment: 1
tab-spam-limit: 500
  book-size:
page-max: 2560
total-multiplier: 0.98
  velocity-support:
enabled: false
online-mode: false
secret: ''
messages:
  no-permission: '&cI''m sorry, but you do not have permission to perform this command.
Please contact the server administrators if you believe that this is in error.'
  kick:
authentication-servers-down: ''
connection-throttle: Connection throttled! Please wait before reconnecting.
flying-player: Flying is not enabled on this server
flying-vehicle: Flying is not enabled on this server
timings:
  enabled: true
  verbose: true
  server-name-privacy: false
  hidden-config-entries:
  - database
  - settings.bungeecord-addresses
  history-interval: 300
  history-length: 3600
  server-name: Unknown Server
world-settings:
  default:
optimize-explosions: false
filter-nbt-data-from-spawn-eggs-and-related: true
max-entity-collisions: 8
disable-creeper-lingering-effect: false
duplicate-uuid-resolver: saferegen
duplicate-uuid-saferegen-delete-range: 32
remove-corrupt-tile-entities: false
per-player-mob-spawns: false
portal-search-radius: 128
fixed-chunk-inhabited-time: -1
use-vanilla-world-scoreboard-name-coloring: false
enable-treasure-maps: true
treasure-maps-return-already-discovered: false
experience-merge-max-value: -1
prevent-moving-into-unloaded-chunks: false
max-auto-save-chunks-per-tick: 24
falling-block-height-nerf: 0
tnt-entity-height-nerf: 0
disable-teleportation-suffocation-check: false
disable-thunder: false
skeleton-horse-thunder-spawn-chance: 0.01
disable-ice-and-snow: false
count-all-mobs-for-spawning: false
keep-spawn-loaded-range: 10
keep-spawn-loaded: true
auto-save-interval: -1
armor-stands-do-collision-entity-lookups: true
nether-ceiling-void-damage-height: 0
water-over-lava-flow-speed: 5
grass-spread-tick-rate: 1
bed-search-radius: 1
use-faster-eigencraft-redstone: false
allow-non-player-entities-on-scoreboards: false
disable-explosion-knockback: false
fix-zero-tick-instant-grow-farms: true
container-update-tick-rate: 1
parrots-are-unaffected-by-player-movement: false
prevent-tnt-from-moving-in-water: false
non-player-arrow-despawn-rate: -1
creative-arrow-despawn-rate: -1
mob-spawner-tick-rate: 1
all-chunks-are-slime-chunks: false
armor-stands-tick: true
spawner-nerfed-mobs-should-jump: false
allow-leashing-undead-horse: false
baby-zombie-movement-modifier: 0.5
hopper:
  cooldown-when-full: true
  disable-move-event: false
alt-item-despawn-rate:
  enabled: false
  items:
    COBBLESTONE: 300
game-mechanics:
  disable-pillager-patrols: false
  scan-for-legacy-ender-dragon: true
  disable-chest-cat-detection: false
  shield-blocking-delay: 5
  disable-end-credits: false
  disable-player-crits: false
  disable-sprint-interruption-on-attack: false
  disable-relative-projectile-velocity: false
  disable-unloaded-chunk-enderpearl-exploit: true
max-growth-height:
  cactus: 3
  reeds: 3
fishing-time-range:
  MinimumTicks: 100
  MaximumTicks: 600
despawn-ranges:
  soft: 32
  hard: 128
lightning-strike-distance-limit:
  sound: -1
  impact-sound: -1
  flash: -1
frosted-ice:
  enabled: true
  delay:
    min: 20
    max: 40
lootables:
  auto-replenish: false
  restrict-player-reloot: true
  reset-seed-on-fill: true
  max-refills: -1
  refresh-min: 12h
  refresh-max: 2d
anti-xray:
  enabled: false
  engine-mode: 1
  chunk-edge-mode: 2
  max-chunk-section-index: 3
  update-radius: 2
  hidden-blocks:
  - gold_ore
  - iron_ore
  - coal_ore
  - lapis_ore
  - mossy_cobblestone
  - obsidian
  - chest
  - diamond_ore
  - redstone_ore
  - clay
  - emerald_ore
  - ender_chest
  replacement-blocks:
  - stone
  - oak_planks
generator-settings:
  flat-bedrock: false
squid-spawn-height:
  maximum: 0.0