Slider won’t work with custom query

I’m trying to set up a slider with the most recent posts from a certain category, but I can’t seem to get it to work.

When I use the regular loop, the slider works just fine, but as soon as I add the new query for the specific category, the slider won’t work anymore – even though the query seems to be working just fine, since I can see other posts – they’re just static and not sliding.

I’m using carouFredSel for the slider, and this is my code:

<div class="wrapper">
    <div class="list_carousel responsive">
        <ul id="desliza">
            <?php $catquery = new WP_Query( 'cat=19' ); while($catquery->have_posts()) : $catquery->the_post(); ?>
                <li>
                    <div class="feattitle"><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title() ;?></a></div>
                    <?php if ( has_post_thumbnail() ) {the_post_thumbnail('destaque', array( 'itemprop' => "image"));} else { ?>
                        <img src="<?php bloginfo('template_directory'); ?>/images/base-thumb.png" alt="<?php the_title(); ?>" />
                    <?php } ?>
                </li>
            <?php endwhile; ?>
        </ul>
    </div>
</div>

Alternative query I’ve tried:

<?php query_posts( 'cat=19' ); ?>
<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>

(And a couple other variations of this.)

What’s the issue, and how can I get the slider to display just one specific category? Thanks.