diff --git a/gerbil-manager-web/src/components/GerbilProfilePhoto.tsx b/gerbil-manager-web/src/components/GerbilProfilePhoto.tsx
new file mode 100644
index 0000000..192986c
--- /dev/null
+++ b/gerbil-manager-web/src/components/GerbilProfilePhoto.tsx
@@ -0,0 +1,20 @@
+/**
+ * FEAT-6: Profilfoto im Detail-Kopf — erstes Foto nach sortOrder.
+ * Selbstständig ladend; rendert nichts, solange es keine Fotos gibt
+ * (oder die Foto-Endpunkte noch nicht live sind).
+ */
+import { listGerbilPhotos, photoSrc, profilePhoto } from '../api/photos'
+import { useApi } from '../hooks/useApi'
+
+export default function GerbilProfilePhoto({ gerbilId }: { gerbilId: string }) {
+  const photos = useApi(() => listGerbilPhotos(gerbilId), [gerbilId])
+  const profile = profilePhoto(photos.data ?? [])
+  if (!profile) return null
+  return (
+    <img
+      className="profile-photo"
+      src={photoSrc(profile)}
+      alt={profile.caption ?? profile.fileName}
+    />
+  )
+}
diff --git a/gerbil-manager-web/src/index.css b/gerbil-manager-web/src/index.css
index 2e244f8..f382e0c 100644
--- a/gerbil-manager-web/src/index.css
+++ b/gerbil-manager-web/src/index.css
@@ -602,3 +602,143 @@ textarea {
   color: #7a5a14;
   margin-left: 0.4rem;
 }
+
+/* ── FEAT-6 (Oscar): Tier-Detail-Tabs — Gesundheit / Gewicht / Fotos ── */
+
+/* Eintragskarten (Gesundheit, Gewichtsverlauf) */
+.record-card {
+  padding: 0.75rem 1rem;
+  border: 1px solid var(--color-border);
+  border-radius: 0.6rem;
+  background: var(--color-surface);
+}
+
+.record-card__head {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 0.5rem;
+}
+
+.record-card__date {
+  font-weight: 600;
+}
+
+.record-card__body {
+  margin: 0.4rem 0;
+  white-space: pre-wrap;
+}
+
+.record-card__actions {
+  display: flex;
+  gap: 0.5rem;
+  margin-top: 0.5rem;
+}
+
+.record-card--row {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 0.75rem;
+}
+
+/* Gewicht-Schnellerfassung: großes, daumenfreundliches Eingabefeld */
+.weight-quick-add {
+  margin-bottom: 1.25rem;
+}
+
+.weight-quick-add__row {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 0.75rem;
+  align-items: flex-end;
+}
+
+.input--xl {
+  font-size: 1.5rem;
+  min-height: 56px;
+  max-width: 9rem;
+  text-align: center;
+}
+
+/* Gewichts-Diagramm (eigenes SVG) */
+.line-chart {
+  width: 100%;
+  height: auto;
+  max-width: 40rem;
+  margin: 0.5rem 0 1.25rem;
+}
+
+.line-chart__axis {
+  stroke: var(--color-text-muted);
+  stroke-width: 1;
+}
+
+.line-chart__grid {
+  stroke: var(--color-border);
+  stroke-width: 1;
+  stroke-dasharray: 3 3;
+}
+
+.line-chart__label {
+  fill: var(--color-text-muted);
+  font-size: 12px;
+}
+
+.line-chart__line {
+  stroke: var(--color-accent);
+  stroke-width: 2;
+}
+
+.line-chart__dot {
+  fill: var(--color-accent);
+}
+
+/* Foto-Galerie */
+.photo-grid {
+  list-style: none;
+  margin: 1rem 0 0;
+  padding: 0;
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(10rem, 1fr));
+  gap: 0.75rem;
+}
+
+.photo-card {
+  border: 1px solid var(--color-border);
+  border-radius: 0.6rem;
+  background: var(--color-surface);
+  overflow: hidden;
+  display: flex;
+  flex-direction: column;
+}
+
+.photo-card img {
+  width: 100%;
+  aspect-ratio: 1;
+  object-fit: cover;
+  display: block;
+}
+
+.photo-card__bar {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 0.4rem;
+  padding: 0.4rem 0.6rem;
+}
+
+.photo-card__caption {
+  font-size: 0.8rem;
+  color: var(--color-text-muted);
+  overflow-wrap: anywhere;
+}
+
+/* Profilfoto im Detail-Kopf */
+.profile-photo {
+  width: 56px;
+  height: 56px;
+  border-radius: 50%;
+  object-fit: cover;
+  border: 2px solid var(--color-border);
+}
diff --git a/gerbil-manager-web/src/pages/GerbilDetailPage.tsx b/gerbil-manager-web/src/pages/GerbilDetailPage.tsx
index b697555..755bbed 100644
--- a/gerbil-manager-web/src/pages/GerbilDetailPage.tsx
+++ b/gerbil-manager-web/src/pages/GerbilDetailPage.tsx
@@ -6,6 +6,11 @@ import { listColorVarieties, listContacts, listEnclosures, listLitters } from '.
 import { useApi } from '../hooks/useApi'
 import { formatDate, genderLabel, statusLabel } from '../format/labels'
 import { fromDisplayString, genotypeToFarbschlag, toDisplayString } from '../genetics'
+// FEAT-6 (Oscar): Tab-Inhalte + Profilfoto
+import GerbilHealthTab from '../components/GerbilHealthTab'
+import GerbilPhotosTab from '../components/GerbilPhotosTab'
+import GerbilProfilePhoto from '../components/GerbilProfilePhoto'
+import GerbilWeightTab from '../components/GerbilWeightTab'
 
 type DetailTab = 'photos' | 'health' | 'weight'
 
@@ -79,6 +84,7 @@ export default function GerbilDetailPage() {
     <section className="page">
       <header className="page-head">
         <div>
+          <GerbilProfilePhoto gerbilId={g.id} />
           <h2>{g.name}</h2>
           <span className={`badge badge--${g.status.toLowerCase()}`}>{statusLabel(g.status)}</span>
         </div>
@@ -158,7 +164,9 @@ export default function GerbilDetailPage() {
         ))}
       </div>
       <div className="tab-panel" role="tabpanel">
-        <p className="muted">{t.detail.tabPlaceholder}</p>
+        {tab === 'photos' && <GerbilPhotosTab gerbilId={g.id} />}
+        {tab === 'health' && <GerbilHealthTab gerbilId={g.id} />}
+        {tab === 'weight' && <GerbilWeightTab gerbilId={g.id} />}
       </div>
     </section>
   )