diff --git a/gerbil-manager-web/e2e/tiere.spec.ts b/gerbil-manager-web/e2e/tiere.spec.ts
index 469edc9..30f7a02 100644
--- a/gerbil-manager-web/e2e/tiere.spec.ts
+++ b/gerbil-manager-web/e2e/tiere.spec.ts
@@ -149,3 +149,26 @@ test('Tier bearbeiten — Notizen ändern', async ({ page }) => {
   await expect(page.getByRole('heading', { name: 'Krümel' })).toBeVisible()
   await expect(page.getByText('Sehr zutraulich.')).toBeVisible()
 })
+
+test('Tier bearbeiten — originBreeder Freitext round-trip (FORM-FIELDS-1)', async ({ page }) => {
+  skipUnlessMock()
+  // Fridolin hat originBreeder='Zoohandlung Meier', kein originContactId → Freitext-Feld vorbelegt
+  await page.goto('/rennmaeuse/fridolin/bearbeiten')
+  await expect(page.getByLabel(t.fields.originBreeder)).toHaveValue('Zoohandlung Meier')
+  await page.getByLabel(t.fields.originBreeder).fill('Neue Musterzucht')
+  await page.getByRole('button', { name: t.form.save, exact: true }).click()
+  // Detailseite: Herkunft zeigt den neuen Wert (kein Contact → originBreeder-Text)
+  await expect(page.getByText('Neue Musterzucht')).toBeVisible()
+})
+
+test('Tier bearbeiten — isDeaf Tristate round-trip (FORM-FIELDS-1)', async ({ page }) => {
+  skipUnlessMock()
+  await page.goto('/rennmaeuse/kruemel/bearbeiten')
+  // Standard: Unbekannt (null → value='')
+  await expect(page.getByLabel(t.fields.isDeaf)).toHaveValue('')
+  await page.getByLabel(t.fields.isDeaf).selectOption({ label: t.form.isDeafYes })
+  await page.getByRole('button', { name: t.form.save, exact: true }).click()
+  // Zurück zur Bearbeiten-Seite: Wert muss erhalten sein
+  await page.goto('/rennmaeuse/kruemel/bearbeiten')
+  await expect(page.getByLabel(t.fields.isDeaf)).toHaveValue('true')
+})
diff --git a/gerbil-manager-web/src/api/types.ts b/gerbil-manager-web/src/api/types.ts
index 40024b2..e9b75f9 100644
--- a/gerbil-manager-web/src/api/types.ts
+++ b/gerbil-manager-web/src/api/types.ts
@@ -54,6 +54,8 @@ export interface Gerbil {
    * as resident (backend default true).
    */
   isResident?: boolean
+  /** FORM-FIELDS-1: true=gehörlos, false=hörend, null=unbekannt. */
+  isDeaf?: boolean | null
 }
 
 /** Payload for POST /gerbils. */
@@ -76,6 +78,7 @@ export interface CreateGerbil {
   characterTraits?: string[] | null
   characterNote?: string | null
   isResident?: boolean
+  isDeaf?: boolean | null
 }
 
 /** Payload for PUT /gerbils/{id} (all optional / partial update). */
diff --git a/gerbil-manager-web/src/pages/GerbilFormPage.tsx b/gerbil-manager-web/src/pages/GerbilFormPage.tsx
index f3eea99..7d38582 100644
--- a/gerbil-manager-web/src/pages/GerbilFormPage.tsx
+++ b/gerbil-manager-web/src/pages/GerbilFormPage.tsx
@@ -21,10 +21,12 @@ interface FormState {
   enclosureId: string
   litterId: string
   originContactId: string
+  originBreeder: string
   receiverContactId: string
   genotype: string
   notes: string
   isResident: boolean
+  isDeaf: boolean | null
 }
 
 const EMPTY: FormState = {
@@ -39,10 +41,12 @@ const EMPTY: FormState = {
   enclosureId: '',
   litterId: '',
   originContactId: '',
+  originBreeder: '',
   receiverContactId: '',
   genotype: '',
   notes: '',
   isResident: true,
+  isDeaf: null,
 }
 
 function formFromGerbil(g: {
@@ -57,10 +61,12 @@ function formFromGerbil(g: {
   enclosureId: string | null
   litterId: string | null
   originContactId: string | null
+  originBreeder?: string | null
   receiverContactId: string | null
   genotype: string | null
   notes: string | null
   isResident?: boolean | null
+  isDeaf?: boolean | null
 }): FormState {
   return {
     name: g.name,
@@ -74,10 +80,12 @@ function formFromGerbil(g: {
     enclosureId: g.enclosureId ?? '',
     litterId: g.litterId ?? '',
     originContactId: g.originContactId ?? '',
+    originBreeder: g.originBreeder ?? '',
     receiverContactId: g.receiverContactId ?? '',
     genotype: g.genotype ?? '',
     notes: g.notes ?? '',
     isResident: g.isResident ?? true,
+    isDeaf: g.isDeaf ?? null,
   }
 }
 
@@ -167,10 +175,12 @@ export default function GerbilFormPage() {
       enclosureId: nn(form.enclosureId),
       litterId: nn(form.litterId),
       originContactId: nn(form.originContactId),
+      originBreeder: nn(form.originBreeder),
       receiverContactId: nn(form.receiverContactId),
       genotype: nn(form.genotype),
       notes: nn(form.notes),
       isResident: form.isResident,
+      isDeaf: form.isDeaf,
     }
     const result = await mutation.run(body)
     if (result.ok) navigate(`/rennmaeuse/${result.value.id}`)
@@ -326,6 +336,16 @@ export default function GerbilFormPage() {
           </select>
         </label>
 
+        <label className="field">
+          <span>{t.fields.originBreeder}</span>
+          <input
+            className="input"
+            value={form.originBreeder}
+            placeholder="z. B. Zucht der Kleinen Chaoten"
+            onChange={(e) => set('originBreeder', e.target.value)}
+          />
+        </label>
+
         <label className="field">
           <span>{t.fields.receiver}</span>
           <select
@@ -360,6 +380,21 @@ export default function GerbilFormPage() {
           <textarea value={form.notes} onChange={(e) => set('notes', e.target.value)} />
         </label>
 
+        <label className="field">
+          <span>{t.fields.isDeaf}</span>
+          <select
+            value={form.isDeaf === null ? '' : String(form.isDeaf)}
+            onChange={(e) => {
+              const v = e.target.value
+              set('isDeaf', v === '' ? null : v === 'true')
+            }}
+          >
+            <option value="">{t.form.isDeafUnknown}</option>
+            <option value="true">{t.form.isDeafYes}</option>
+            <option value="false">{t.form.isDeafNo}</option>
+          </select>
+        </label>
+
         <label className="field field--check" title={t.form.isResidentHint}>
           <span>{t.form.isResidentLabel}</span>
           <input
diff --git a/gerbil-manager-web/src/strings/de.ts b/gerbil-manager-web/src/strings/de.ts
index 3b74beb..5e8b2c1 100644
--- a/gerbil-manager-web/src/strings/de.ts
+++ b/gerbil-manager-web/src/strings/de.ts
@@ -80,6 +80,8 @@ export const de = {
         enclosure: 'Gehege',
         colorVariety: 'Farbschlag',
         origin: 'Herkunft',
+        originBreeder: 'Herkunft (Freitext)',
+        isDeaf: 'Gehörlos',
         receiver: 'Abnehmer',
         genotype: 'Genotyp',
         notes: 'Notizen',
@@ -114,6 +116,9 @@ export const de = {
         // BESTAND-FILTER: Zugehörigkeit zum eigenen Bestand (sonst externe Ahne)
         isResidentLabel: 'Gehört zum eigenen Bestand',
         isResidentHint: 'Abwählen für externe Ahnen, die nur für den Stammbaum erfasst sind.',
+        isDeafUnknown: 'Unbekannt',
+        isDeafYes: 'Ja',
+        isDeafNo: 'Nein',
         save: 'Speichern',
         cancel: 'Abbrechen',
         saving: 'Speichern …',