Masters Theses

Date of Award


Degree Type


Degree Name

Master of Science


Animal Husbandry

Major Professor

Sam L. Hansard

Committee Members

E. R. Lindvall, S. A. Griffin, Robert R. Shrode


Data from 16 sows and litters in 4 treatment groups were analyzed by least-squares techniques to determine the effects of a pasture en-vironment and forage consumption on lactating sows and nursing pigs. Weight changes in the sows, corrected 56-day pig weights, feed records of sows and litters, analysis of sow feces, hemoglobin and hematocrit values, and various plasma mineral analysis were used as criteria. The mean weight change of self-fed sows without forage in con-finement was significantly higher (P>0.05) than the mean weight changes of sows control-fed with cut forage ad lib, in confinement, control-fed on pasture, or control-fed without forage in confinement. All control-fed sows lost weight while the self-fed sows gained weight. Consumption of fresh cut forage was measured in confinement and used as an estimate of forage consumption by sows on pasture. The average daily intake was 1.19 kilograms of fresh forage and the highest intake recorded for any given day was 3.09 kilograms. Sows and pigs in the control-fed group with forage ad lib, in confinement required less feed per ICQ kilograms of litter gain (315.33 kilograms). However, differences in feed requirements among the control-fed groups were small when compared to the self-fed group which consumed from 51 to 70 percent more feed per 100 kilograms of litter gain. Pigs on pasture consumed considerably more creep feed, but this did not result in proportionally heavier pigs at weaning. Mean corrected 56-day pig weights did not differ significantly between treatments (P >0.05). However, pigs in the control-fed group on pasture were slightly heavier while pigs in the self-fed group without forage in confinement were lighter. Treatment differences in the number of pigs weaned per litter were not significant (P>0.05). Mineral analysis of feeds, forages, and feces indicated a higher fecal excretion by sows on pasture probably due to a higher forage intake than that measured in confinement. Treatment differences in hemoglobin and hematocrit values of sow blood at 21 and 56 days after farrowing did not prove to be significant (P>0.05). Pigs in the control-fed group with forage ad lib, in con-finement had significantly higher (P>0.10) hemoglobin values than pigs in the control-fed groups without forage in confinement at 21 days of age. At this time, hematocrit values were significantly higher (P>0.10) in the pigs on pasture. At 56 days of age, hemoglobin and hematocrit values did not differ significantly (P>0.10) between treatments. Sow plasma mineral concentrations were not significantly different (P>0.10) between treatments at 21 and 56 days after farrowing, with the exception of 56-day inorganic phosphorus. The self-fed sows were found to have consistently higher inorganic phosphorus values at 56 days after farrowing. Mineral concentrations of pig plasma did not differ signi-ficantly (P>0.10) between treatments at either 21 or 56 days of age. Very high relationships were found to exist among certain blood components and weaning weights of pigs.

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