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Twenty-one mixed-parity (average 2.4 ± 0.49) crossbred sows and their offspring were used to determine whether sow milk leptin at farrowing was re- lated to neonatal serum leptin and pig growth to wean- ing. During farrowing, pigs were randomly allotted to suckling (n = 99) or delayed suckling (n = 89) groups, with delayed suckling pigs placed in a group pen apart from the dam before suckling. Both groups had access to heat lamps. Colostrum samples were collected no more than 2 h after farrowing the first pig. Blood sam- ples were collected from all pigs approximately 2 h af- ter farrowing was complete; pigs were then ear notched and returned to their dams. Pig BW was recorded at 1.2 ± 0.04 d of age and again at weaning. Milk and blood serum were collected after centrifugation; leptin concentrations were estimated using RIA. Leptin was detected in colostral milk, as expected, and averaged 46.0 ± 1.1 ng/mL. Pig serum leptin (P < 0.02) was greater in suckling pigs than in delayed suckling pigs, averaging 0.69 ± 0.08 and 0.54 ± 0.07 ng/mL, respec- tively. Although male pigs were heavier (P < 0.01) at birth than female pigs (1,507 ± 52 vs. 1,381 ± 43 g), ADG to weaning and weaning weights were similar for both sexes, averaging 229 ± 14 g and 5,829 ± 323 g, re- spectively, for all pigs; serum leptin concentrations were not affected by sex of the pig. Milk serum leptin was not associated with litter size, parity, pig birth weight, ADG to weaning, or weaning weight. Suckling status did not influence ADG to weaning or weaning weight of pigs; neonatal pig serum leptin was not related to birth weight, weaning weight, or ADG to weaning. These results indicate that leptin is not directly related to early neonatal growth in the pig; however, more in- depth studies are needed to determine possible indirect or long-term effects of early leptin exposure.

Thousands of hectares of timothy (Phleum pretense L.) grown in the Mid-Atlantic region are infected by cereal rust mite (Abacarus hysterix) that causes discoloration and curling of leaves, decreased nutritional quality, and substantial decreases in yield. A decline in production of timothy hay can lower income for hay producers and cause horse owners to search for alternative hays. Low alkaloid reed canarygrass (Phalaris arundinacea L.) hay has potential as an alternative to timothy hay because it grows well in the Mid-Atlantic region, is believed to have a similar nutrient quality to timothy, and is not as susceptible to cereal rust mite. Eleven mature, stalled Thoroughbred geldings (549 +/- 12.1 kg) that were exercised daily were used to compare voluntary DMI and apparent nutrient DM digestibility of timothy and low-alkaloid Chiefton variety reed canarygrass hay. Horses were paired by age and BW and randomly assigned to timothy or reed canarygrass hay during a 14-d period to measure voluntary DMI followed by a 4-d period to measure apparent DM digestibility. Both hays met the minimum requirements for DE, CP, Ca, P, K, Fe, and Mn, but they did not meet the minimum requirements for Cu, Zn, and Na for horses at maintenance and averaging 550 kg of BW. Timothy hay seemed to have a lower CP concentration (14.4%) compared with reed canarygrass hay (17.1%) and a more desirable Ca:P ratio at 1.6:1 compared with 0.8:1 for reed canarygrass hay. Horses fed timothy consumed more hay (P