不如

[^,\s]+(,[^,\s]+)+

其将匹配一个或多个不是空格或逗号的字符[^,\s]+，后面是逗号，以及一个或多个不是空格或逗号的字符，一次或多次。

• 补充意见 *

要匹配多个序列，请添加g修饰符以进行全局匹配。
下面的代码在,上拆分每个匹配$&，并将结果推送到@matches。

my $str = "sdfds cat_dog,horse,rabbit,chicken-pig then some more pig,duck,goose";
my @matches;

while ($str =~ /[^,\s]+(,[^,\s]+)+/g) {
    push(@matches, split(/,/, $&));
}   

print join("\n",@matches),"\n";

虽然您可能可以构造单个正则表达式，但是正则表达式、split s、grep和map的组合看起来很不错

my @array = map { split /,/ } grep { !/^,/ && !/,$/ && /,/ } split

从右到左：
1.按空格拆分行（split）
1.仅保留两端没有逗号但内部有逗号的元素（grep）
1.将每个此类元素拆分为部分（map和split）
这样，您就可以轻松地更改部件，例如删除grep中的两个连续逗号add && !/,,/。

我希望这是明确的，并符合您的需要：

#!/usr/bin/perl
    use warnings;
    use strict;

    my @strs = ("ewrfs sdfdsf cat_dog,horse,rabbit,chicken-pig",
    "fdsf iiukui aawwe dffg elephant,MOUSE_RAT,spider,lion-tiger hdsfds jdlkf sdf", 
     "dsadp poids pewqwe ANTELOPE-GIRAFFE,frOG,fish,crab,kangaROO-KOALA sdfdsf hkew", 
     "Saturn was long thought to be the only ringed planet, however, this is now known not to be the case.",
     "Another sentence, although having commas, should not confuse the regex with this: a,b,c,d");

    my $regex = qr/
                \s #From your examples, it seems as if every
                   #comma separated list is preceded by a space.
                (
                    (?:
                        [^,\s]+ #Now, not a comma or a space for the
                                 #terms of the list

                        ,        #followed by a comma
                    )+
                    [^,\s]+     #followed by one last term of the list
                )
                /x;

    my @matches = map {
                    $_ =~ /$regex/;
                    if ($1) {
                        my $comma_sep_list = $1;
                        [split ',', $comma_sep_list];
                    }
                    else {
                        []
                    }
                } @strs;

$var =~ tr/ //s;    
while ($var =~ /(?<!, )\b[^, ]+(?=,\S)|(?<=,)[^, ]+(?=,)|(?<=\S,)[^, ]+\b(?! ,)/g) {
      push (@arr, $&);
    }

正则表达式匹配三种情况：

(?<!, )\b[^, ]+(?=,\S) : matches cat_dog
(?<=,)[^, ]+(?=,)      : matches horse & rabbit
(?<=\S,)[^, ]+\b(?! ,) : matches chicken-pig