Changes in follicular dynamics were monitored in forty-four Brahman multiparous (n=30) and primiparous (n=14) cows randomly assigned to control (n=22) and once-daily suckling (n=22) treatments. Daily transrectal ultrasonography images were taken from d 21 through 88 post-calving or detection of first estrus. Suckling treatment was introduced on d 28 post-calving. Follicular waves were profiled and characterized by development and regression of a variable number of small and medium sized (2-9 mm) follicles before one of the follicles differentiated and became the dominant follicle. Primiparous cows had 34% more (P<0.04) follicular waves (4.8 + 0.6) than did the multiparous cows (3.1 + 0.4) prior to first ovulation (FO). Once-daily suckled multiparous cows had 37% fewer (P<0.03) follicular waves (2.4 + 0.5) prior to FO than controls. Interval from calving to FO was reduced (P < 0.05) by an average of 12 d by once-daily suckling in multiparous cows. Primiparous cows developed 30% more (P<0.02) dominant follicles (6.3 + 0.6) from d 21 to estrus than did the multiparous cows (4.3 + 0.4). Ovulation before d 88 occurred in 42 of 44 (95%) cows. Behavioral estrus was not detected in 40 of 42 (95%) cows at FO. The length of the subsequent estrous cycle was short (<17 days) in 39 of 42 (93%) cows. We can conclude from these data that ovarian function is resumed shortly after parturition and ovulation of a dominant follicle ends postpartum anestrous. Primiparous cows experienced more follicular waves and therefore grew more dominant follicles prior to first estrus. Once-daily suckling hastened return to estrus and reduced the number of follicular waves prior to first post-partum estrus in multiparous cows. The incidence of first ovulation being associated with behavioral estrus was low. Short cycles followed first ovulation. It appears obligatory that postpartum Brahman cows experience a silent ovulation with formation of functional luteal tissue prior to resumption of normal estrous cyclicity.

Changes in follicular dynamics were monitored in forty-four Brahman multiparous (n=30) and primiparous (n=14) cows randomly assigned to control (n=22) and once-daily suckling (n=22) treatments. Daily transrectal ultrasonography images were taken from d 21 through 88 post-calving or detection of first estrus. Suckling treatment was introduced on d 28 post-calving. Follicular waves were profiled and characterized by development and regression of a variable number of small and medium sized (2-9 mm) follicles before one of the follicles differentiated and became the dominant follicle. Primiparous cows had 34% more (P<0.04) follicular waves (4.8 + 0.6) than did the multiparous cows (3.1 + 0.4) prior to first ovulation (FO). Once-daily suckled multiparous cows had 37% fewer (P<0.03) follicular waves (2.4 + 0.5) prior to FO than controls. Interval from calving to FO was reduced (P < 0.05) by an average of 12 d by once-daily suckling in multiparous cows. Primiparous cows developed 30% more (P<0.02) dominant follicles (6.3 + 0.6) from d 21 to estrus than did the multiparous cows (4.3 + 0.4). Ovulation before d 88 occurred in 42 of 44 (95%) cows. Behavioral estrus was not detected in 40 of 42 (95%) cows at FO. The length of the subsequent estrous cycle was short (<17 days) in 39 of 42 (93%) cows. We can conclude from these data that ovarian function is resumed shortly after parturition and ovulation of a dominant follicle ends postpartum anestrous. Primiparous cows experienced more follicular waves and therefore grew more dominant follicles prior to first estrus. Once-daily suckling hastened return to estrus and reduced the number of follicular waves prior to first post-partum estrus in multiparous cows. The incidence of first ovulation being associated with behavioral estrus was low. Short cycles followed first ovulation. It appears obligatory that postpartum Brahman cows experience a silent ovulation with formation of functional luteal tissue prior to resumption of normal estrous cyclicity.

Th.--Lett.--Paris 4, 1979.

In their first days of life, dairy calves in artificial rearing systems often have difficulty using an artificial teat for feeding. I examined the age at which calves are able to stand up and suckle without lifting assistance, as well as their suckling behavior when presented with a plain dry teat versus a dry teat modified with a presumably attractive odor or taste substance. Single-housed newborn dairy calves (n = 51) were presented for ten consecutive days with a two-minute two-choice test, in which suckling time was recorded for 1) a plain (control) teat vs. a glucose-coated teat (taste test) and 2) a plain teat vs. a teat with a "Freshly Cut Grass" odor (odor test). On average, the calves were able to suckle without lifting assistance from the second or third day of age on. The "Freshly Cut Grass" odor had no significant effect on their suckling behavior. The calves showed a significant preference for suckling the glucose-coated teat and displayed a significantly longer total suckling time in the taste test compared to the odor test. There were no significant differences between sexes regarding suckling preference. The results of the present study show that glucose had a significant effect on the calves' teat preference and significantly increased total suckling time with a dry artificial teat. As such, glucose may increase suckling motivation in non-efficient drinkers or ill calves with low motivation to suckle.

No description available.

Doctor of Philosophy / Department of Animal Sciences and Industry / Duane L. Davis / Jim L. Nelssen / A total of 188 sows and their litters were used in 2 experiments to evaluate methods to induce estrus and ovulation in lactating sows and effects on pig growth. In Exp. 1, an altered suckling method (ALT) was designed to combine split-weaning and intermittent suckling as a means to reduce the suckling stimulus in primi- and multiparous sows during the last week of lactation (d 18 to 25). The ALT sows were also removed for daily boar exposure. The ALT treatment produced lactational estrus in 75% and 95% of primiparous and multiparous sows, respectively. The ALT sows were in estrus earlier (P < 0.01) than controls post-farrowing, with no effect on subsequent reproductive performance. From d 18 to 32, the ALT treatment benefited (P < 0.01) growth of lightweight pigs but decreased (P < 0.01) BW gain of heavyweight pigs, resulting in overall similar growth. However, variation in BW was reduced (P < 0.01) by 50% for ALT litters. In Exp. 2, varying suckling reduction strategies were applied to boar-exposed lactating sows. Overall, 76% of sows in suckling reduction treatments expressed estrus in lactation. Split-weaned and ALT sows performed reproductively similar to controls, whereas sows with daily litter separation or a single 24 h litter removal tended (P < 0.10) to have reduced conception rates versus controls or split-weaned sows. Reduced suckling treatments differed in their ability to induce lactational estrus and impact on pig BW gain immediately post-weaning. However, no evidence was found of benefit for pig growth to market weight or litter BW variation. Four additional experiments using 902 nursery pigs were conducted to test the efficacy of potential detoxifying agents against deoxynivalenol (DON) in swine diets. The effects of DON were not offset by adding an algae-modified montmorillonite clay nor by a proprietary blend of preservatives and clays. However, hydrothermally treating DON-contaminated diets with sodium metabisulfite modified the structure of DON to a non-toxic DON-sulfonate adduct and restored nursery pig growth via improved (P < 0.05) ADG, ADFI and G:F.

For centuries Aloe vera has been exploited for several verified and unverified medicinal uses such as wound healing, treatment of gastrointestinal ulcers and for its many biological effects including anti-microbial, laxative, anti-inflammatory and immunostimulatory activities. Studies have generally focused on its effects in vitro and in adults. When nursing mothers use Aloe vera extracts, their suckling infants are at risk of indirect exposure to Aloe vera via breast feeding or directly as dietary/health supplements. The gastrointestinal tract (GIT) of the neonate is sensitive to dietary manipulations during the suckling period with long lasting effects that can be irreversible. Thus babies may be at risk if administered Aloe vera extracts directly as dietary supplements or indirectly via breast milk. The main objectives of this study were to evaluate the effects of orally administered aqueous and alcohol extracts of Aloe vera on growth performance, the morphometry and morphology of the gastrointestinal tract and accessory organs, and liver function of suckling rats. Suckling Sprague-Dawley rats (77), males (n=38) and females (n=39) of 6 days old were randomly assigned to one of five treatment groups and given once daily by oral gavage a suspension of lyophilized crude alcohol or aqueous extracts of Aloe vera suspended in distilled water. Group I (control) was gavaged with distilled water (vehicle). Group II received a low dose of the aqueous extract (AqL) at 50mg. kg-1; Group III received a high dose of the aqueous extract (AqH) at 500mg. kg-1; Group IV received a low dose of the alcohol extract (AlcL) at 50mg. kg-1 whilst Group V received a high dose of the alcohol extract (AlcH) at 500mg. kg-1. The extracts and distilled water were 2 administered at a volume of 10ml.kg-1. The pups remained with their dams for the duration of the study and after 8 days on the treatments, the pups were humanely killed to harvest their tissues for measurements and physiological analysis. All data were expressed as mean ± SD and analyzed by one way ANOVA, the values were considered statistically significant when p < 0.05 and then a Bonferroni Post hoc test was applied. The suckling rats fed respectively with high doses of AlcH and AqH had a significantly higher body mass gain than the other groups (p < 0.05, one way ANOVA). Linear growth as measured by tibial length was significantly increased in the AqH group compared to the other groups. There was no significant difference in the mass and relative density of the tibia bones of the rats from the different treatment groups. The differences in growth could not be attributed to circulating concentrations of the somatotrophic hormone, Insulin-like growth factor-1 (IGF-1) which was not significantly different between the groups. The treatments did not result in any significant differences in lengths, and mass of the small and large intestine, however the caecum was significantly enlarged (hypertrophy of muscularis, submucosa and mucosa) in the rats that received the Aloe vera extracts. Although, there was no significant difference in the mass of the rats’ livers, the lipid and glycogen content were significantly higher (p < 0.001) for the AqH group compared to the other groups. Histologically, the hepatocytes showed enlarged nuclei, granular cytoplasm and dilated sinusoids for AqH and AlcH as compared to the control group. An indirect assessment of liver function by measurement of blood concentrations of alkaline phosphatase (ALP) and alanine amino transaminase (ALT) did not reveal a significant difference between the groups. The non fasting concentration of metabolic substrates (glucose and triglycerides) was also not significantly different between the groups. The pups given high doses of the extracts had a significantly greater (p < 0.05) thymus mass (hyperplastic) than the other groups. The short term administration of Aloe vera extracts has shown a growth promoting effect, enhanced hepatic storage of metabolic substrates and hypertrophy of the caecum and thymus of neonatal rats. These effects need to be explored further to enhance animal production and health.

Inaug.-diss.--University Rostock. / Includes bibliographical references.

Thesis (Ph.D.)--Virginia Commonwealth University, 2005. / Prepared for: Dept. of Anatomy and Neurobiology. Bibliography: leaves 75-83. Also available online.

Thesis (Ph. D.) -- Virginia Commonwealth University, 2005. / Title from title-page of electronic thesis. Prepared for: Dept. of Anatomy and Neurobiology. Bibliography: leaves 75-83.