Looks like a food issue

Waldo threw exception in WorkGiver Train: System.NullReferenceException: Object reference not set to an instance of an object
at (wrapper dynamic-method) AnimalControls.Patch.FoodUtility_FoodOptimality.AnimalControls.Patch.FoodUtility_FoodOptimality.Postfix_Patch0(single&,Verse.Pawn,Verse.Thing,Verse.ThingDef,single,bool)
at (wrapper dynamic-method) RimWorld.FoodUtility.RimWorld.FoodUtility.FoodOptimality_Patch4(Verse.Pawn,Verse.Thing,Verse.ThingDef,single,bool)
at (wrapper dynamic-method) RimWorld.FoodUtility.RimWorld.FoodUtility.SpawnedFoodSearchInnerScan_Patch1(Verse.Pawn,Verse.IntVec3,System.Collections.Generic.List`1<Verse.Thing>,Verse.AI.PathEndMode,Verse.TraverseParms,single,System.Predicate`1<Verse.Thing>)
at (wrapper dynamic-method) RimWorld.FoodUtility.RimWorld.FoodUtility.BestFoodSourceOnMap_NewTemp_Patch4(Verse.Pawn,Verse.Pawn,bool,Verse.ThingDef&,RimWorld.FoodPreferability,bool,bool,bool,bool,bool,bool,bool,bool,bool,bool,bool,RimWorld.FoodPreferability,System.Nullable`1<single>,bool)
at (wrapper dynamic-method) RimWorld.WorkGiver_InteractAnimal.RimWorld.WorkGiver_InteractAnimal.TakeFoodForAnimalInteractJob_Patch0(RimWorld.WorkGiver_InteractAnimal,Verse.Pawn,Verse.Pawn)
at (wrapper dynamic-method) RimWorld.WorkGiver_Train.RimWorld.WorkGiver_Train.JobOnThing_Patch4(RimWorld.WorkGiver_Train,Verse.Pawn,Verse.Thing,bool)
at (wrapper dynamic-method) RimWorld.WorkGiver_Scanner.RimWorld.WorkGiver_Scanner.HasJobOnThing_Patch1(RimWorld.WorkGiver_Scanner,Verse.Pawn,Verse.Thing,bool)
at RimWorld.JobGiver_Work+<>c__DisplayClass3_1.<TryIssueJobPackage>b__0 (Verse.Thing t) [0x00013] in <617d4a4b3c1842ffb4eb3fd1337f915c>:0
at Verse.GenClosest+<>c__DisplayClass2_0.<ClosestThingReachable>b__0 (Verse.Thing t) [0x00034] in <617d4a4b3c1842ffb4eb3fd1337f915c>:0
at Verse.GenClosest.<ClosestThing_Global>g__Process|5_0 (Verse.Thing t, Verse.GenClosest+<>c__DisplayClass5_0& ) [0x00047] in <617d4a4b3c1842ffb4eb3fd1337f915c>:0
at Verse.GenClosest.ClosestThing_Global (Verse.IntVec3 center, System.Collections.IEnumerable searchSet, System.Single maxDistance, System.Predicate`1[T] validator, System.Func`2[T,TResult] priorityGetter) [0x00125] in <617d4a4b3c1842ffb4eb3fd1337f915c>:0
at Verse.GenClosest.ClosestThingReachable (Verse.IntVec3 root, Verse.Map map, Verse.ThingRequest thingReq, Verse.AI.PathEndMode peMode, Verse.TraverseParms traverseParams, System.Single maxDistance, System.Predicate`1[T] validator, System.Collections.Generic.IEnumerable`1[T] customGlobalSearchSet, System.Int32 searchRegionsMin, System.Int32 searchRegionsMax, System.Boolean forceAllowGlobalSearch, Verse.RegionType traversableRegionTypes, System.Boolean ignoreEntirelyForbiddenRegions) [0x0014c] in <617d4a4b3c1842ffb4eb3fd1337f915c>:0
at (wrapper dynamic-method) RimWorld.JobGiver_Work.RimWorld.JobGiver_Work.TryIssueJobPackage_Patch3(RimWorld.JobGiver_Work,Verse.Pawn,Verse.AI.JobIssueParams)
UnityEngine.StackTraceUtility:ExtractStackTrace ()
(wrapper dynamic-method) Verse.Log:Verse.Log.Error_Patch6 (string)
(wrapper dynamic-method) RimWorld.JobGiver_Work:RimWorld.JobGiver_Work.TryIssueJobPackage_Patch3 (RimWorld.JobGiver_Work,Verse.Pawn,Verse.AI.JobIssueParams)
(wrapper dynamic-method) Verse.AI.ThinkNode_PrioritySorter:Verse.AI.ThinkNode_PrioritySorter.TryIssueJobPackage_Patch0 (Verse.AI.ThinkNode_PrioritySorter,Verse.Pawn,Verse.AI.JobIssueParams)
(wrapper dynamic-method) Verse.AI.ThinkNode_Priority:Verse.AI.ThinkNode_Priority.TryIssueJobPackage_Patch0 (Verse.AI.ThinkNode_Priority,Verse.Pawn,Verse.AI.JobIssueParams)
Verse.AI.ThinkNode_Tagger:TryIssueJobPackage (Verse.Pawn,Verse.AI.JobIssueParams)
Verse.AI.ThinkNode_Subtree:TryIssueJobPackage (Verse.Pawn,Verse.AI.JobIssueParams)
(wrapper dynamic-method) Verse.AI.ThinkNode_Priority:Verse.AI.ThinkNode_Priority.TryIssueJobPackage_Patch0 (Verse.AI.ThinkNode_Priority,Verse.Pawn,Verse.AI.JobIssueParams)
Verse.AI.ThinkNode_Conditional:TryIssueJobPackage (Verse.Pawn,Verse.AI.JobIssueParams)
(wrapper dynamic-method) Verse.AI.ThinkNode_Priority:Verse.AI.ThinkNode_Priority.TryIssueJobPackage_Patch0 (Verse.AI.ThinkNode_Priority,Verse.Pawn,Verse.AI.JobIssueParams)
(wrapper dynamic-method) Verse.AI.Pawn_JobTracker:Verse.AI.Pawn_JobTracker.DetermineNextJob_Patch4 (Verse.AI.Pawn_JobTracker,Verse.ThinkTreeDef&)
Verse.AI.Pawn_JobTracker:TryFindAndStartJob ()
(wrapper dynamic-method) Verse.AI.Pawn_JobTracker:Verse.AI.Pawn_JobTracker.EndCurrentJob_Patch9 (Verse.AI.Pawn_JobTracker,Verse.AI.JobCondition,bool,bool)
(wrapper dynamic-method) Verse.AI.Pawn_JobTracker:Verse.AI.Pawn_JobTracker.JobTrackerTick_Patch0 (Verse.AI.Pawn_JobTracker)
(wrapper dynamic-method) Verse.Pawn:Verse.Pawn.Tick_Patch4 (Verse.Pawn)
(wrapper dynamic-method) Verse.TickList:Verse.TickList.Tick_Patch2 (Verse.TickList)
(wrapper dynamic-method) Verse.TickManager:Verse.TickManager.DoSingleTick_Patch10 (Verse.TickManager)
Verse.TickManager:TickManagerUpdate ()
(wrapper dynamic-method) Verse.Game:Verse.Game.UpdatePlay_Patch2 (Verse.Game)
(wrapper dynamic-method) Verse.Root_Play:Verse.Root_Play.Update_Patch1 (Verse.Root_Play)