Shepherds solution
by Kegler
As described by the main diagonal, BORDER COLLIES, a "collie" is found on each "border" of the grid.
Across
| 1 | BRONCO (hidden) |
| 7 | LI(EG)ES |
| 13 | B(I)EN + NIA + L |
| 14 | sCARED |
| 15 | O(F)T |
| 17 | VIE (odd letters) |
| 18 | S + EDGE |
| 19 | EASY ("E Z" hom) |
| 21 | LT + D |
| 22 | SCRA[P/m] |
| 23 | BAUD RATE (READ ABoUT anag) |
| 25 | LAIC (1st letters) |
| 27 | CAR(BON + COP + I)ES |
| 29 | OUTLOOK (TOOK LOU anag) |
| 30 | ON + C + ALL |
| 34 | L + APE + L |
| 36 | LAUR(E)A + TE |
| 38 | bILLS |
| 40 | ADENOSINE (rev hidden) |
| 41 | EXOTIC DANCER (CRETIN COAXED anag) |
| 42 | PROTOCOL ("PRO TO CALL" hom) |
| 43 | LIENS (LINES anag) |
|
Down
| 1 | B + U + COLIC |
| 2 | RO(A'S)T |
| 3 | OAR(E)D (A-ROD anag) |
| 4 | CA(D)GED |
| 5 | hOBOES |
| 6 | LIFE JACKET (JACKIE FELT anag) |
| 8 | IN ESSE (hidden) |
| 9 | ENCYCLICALS (CICELY'S CLAN anag) |
| 10 | GIVER (hidden) |
| 11 | SLEEP (rev) |
| 12 | RED + O + UBLE (BLUE anag) |
| 16 | TATTOO (2 defs) |
| 20 | P(AISLE),Y |
| 24 | A(TRFU)L (TURF anag) |
| 26 | CO + L + LIERS (RILES anag) |
| 28 | NOMAD + I + C (DAMON rev) |
| 29 | O + LLI + E (ILL rev) |
| 31 | PALER (PEARL anag) |
| 32 | N(E)ATO |
| 33 | LEND + L |
| 35 | PRInCE |
| 37 | G(O)AL |
| 39 | SO + T |
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