(ShareCast News) - Pet products and services retailer Pets at Home Group said its trading was in line with annual expectations, as it reported an increase in first half sales.In the seven months to 8 October, the FTSE 250 group said like-for-like sales grew 1.8% year-on-year, driven by solid performances in its services, advanced nutrition and VIP Club divisions, which offset weakness in the health and hygiene business.Like-for-like revenue in the merchandise division rose 1%, while they surged 11% in the services arm.Total revenue rose 6% year-on-year to £404.5m, driven higher by a 26% increase in services revenue and by a 4.1% gain in the merchandise business.In a trading update released on Friday, the group said it remained confident of meeting its full-year target in terms of new stores, vet practices and grooming salons."Whilst trading in parts of the business has been weaker than expected, the core strategic drivers are performing well and in order to support their growth, we continue to invest in our colleagues and seamless shopping experience," said group chief executive Nick Wood.Pets at Home Group shares were down 7.13% to 289.00p at 0821 GMT on Friday.