65,000 sheep skin cDNA clones were gridded in high density on to nylon membranes and screened for... more 65,000 sheep skin cDNA clones were gridded in high density on to nylon membranes and screened for (CA)n and (GA)n repeat containing clones. 296 dinucleotide repeat-containing clones were identified with ∼85% non-redundancy. Clones were single-pass 5′ sequenced and we compared the Expressed Sequence Tag (EST) sequences to the Swiss-Prot database to ascertain their identity and/or putative function. We then aligned the ESTs against the human genomic sequence to determine the locations of human orthologous sequences. Finally, we developed a subset of polymorphic microsatellite markers and positioned them on the ovine linkage map.
Timing of conceptus growth and attachment to the uterine luminal epithelium is regulated by proge... more Timing of conceptus growth and attachment to the uterine luminal epithelium is regulated by progesterone secretion from the corpus luteum and by expression of progesterone receptor in the uterine epithelia and stroma. Conceptus growth and uterine attachment are temporally associated with the disappearance of progesterone receptors from uterine epithelia. While the loss of progesterone receptor from the endometrial epithelia on day 10 of the oestrous cycle and pregnancy has been well documented, the factors involved with cell specific down-regulation of progesterone receptor are yet to be established. We propose that several progesterone stimulated factors activate nuclear factor kappa B (NF-kB) within the uterine epithelia, which leads to inhibition of progesterone receptor and concomitant stimulation of endometrial genes expressed during early conceptus development. Although oestrogens secreted by pig conceptuses function to establish pregnancy, timing of endometrial exposure to oestrogen is critical. Early oestrogen administration alters the pattern of gene expression through the NF-kB system desynchronising the uterine environment for conceptus implantation resulting in later embryonic loss.
Cathelicidins are an important family of cationic host defense peptides in vertebrates with both ... more Cathelicidins are an important family of cationic host defense peptides in vertebrates with both antimicrobial and immunomodulatory activities. Fowlicidin‐1 and fowlicidin‐2 are two newly identified chicken cathelicidins with potent antibacterial activities. Here we report structural and functional characterization of the putatively mature form of the third chicken cathelicidin, fowlicidin‐3, for exploration of its therapeutic potential. NMR spectroscopy revealed that fowlicidin‐3 comprises 27 amino‐acid residues and adopts a predominantly α‐helical structure extending from residue 9 to 25 with a slight kink induced by a glycine at position 17. It is highly potent against a broad range of Gram‐negative and Gram‐positive bacteria in vitro, including antibiotic‐resistant strains, with minimum inhibitory concentrations in the range 1–2 µm. It kills bacteria quickly, permeabilizing cytoplasmic membranes immediately on coming into contact with them. Unlike many other host defense peptides with antimicrobial activities that are diminished by serum or salt, fowlicidin‐3 retains bacteria‐killing activities in the presence of 50% serum or physiological concentrations of salt. Furthermore, it is capable of suppressing lipopolysaccharide‐induced expression of proinflammatory genes in mouse macrophage RAW264.7 cells, with nearly complete blockage at 10 µm. Fowlicidin‐3 appears to be an excellent candidate for future development as a novel antimicrobial and antisepsis agent, particularly against antibiotic‐resistant pathogens.
It is generally accepted that “temperamental” cattle are more anxious or experience higher stress... more It is generally accepted that “temperamental” cattle are more anxious or experience higher stress, causing differences in intake and performance. The objective of this study was to examine whether temperament affects how steers perform during prolonged water restriction, a chronic stressor. Steers from numerous sources in 4 groups (n = 469) were randomly allocated to 2 weight blocks. Steers were fed ad libitum 3 times a day for 70 d. After a 28 d step-down period, steers were maintained at 50% of normal water allotment for 42 d while feed continued to be offered ad libitum. Individual feed and water intake (WI) were measured daily using an Insentec RIC feeding system. Body weight, exit velocity (EV; measured over 1.5m), and chute score (CS; reported on a 1–4 scale) were measured every 14 d. Lower scores indicate calmer temperament. Due to the study design, DMI, ADG, G:F, and WI were split into 7 periods (d 0–28, 28–70, 0–70, 98–140, 98–112, 112–126, and 126–140). Data were analyzed using the MIXED procedure of SAS where the model included EV, CS, the interaction, and block; group was included as a random effect. Gain, DMI, and G:F d 0–28 were affected by both CS and EV. Slow EV steers had higher DMI than fast EV steers (P < 0.02) during d 28–70 and 0–70. During d 28–70, intermediate CS steers had the highest DMI (P < 0.05). During d 0–70 and 98–140, intermediate CS steers had the highest ADG (P < 0.05). All measures of DMI and WI were higher in the heavy weight block (P < 0.05); ADG and G:F were also higher in the heavy weight block during d 0–70 (P < 0.001). This experiment indicates that there may be performance benefits for steers with intermediate CS during long periods of water restriction.
Reducing dietary crude protein (CP) beyond a certain threshold leads to poor growth performance i... more Reducing dietary crude protein (CP) beyond a certain threshold leads to poor growth performance in pigs; however, the underlying mechanisms are not well understood. Following an adaption period, thirty-seven weaned pigs were weight matched (8.41 ± 0.14 kg), housed individually and randomly assigned into three groups with different dietary CP levels: 24% CP (CON; n = 12), 18% CP (n = 12) and 12% CP (n = 13) for 28 days. The body weight was not different between the CON and 18% CP diets, but 12% CP significantly decreased body weight after day 21. Compared to the CON, pigs fed with 12% CP decreased feed intake day 17 onwards. The 12% CP diet increased the energy expenditure during week 1 compared to the CON. The 12% CP influenced starch and sucrose, nitrogen, and branched-chain amino acids metabolism pathways. The feces of pigs fed with 12% CP were less enriched in Prevotella, but had higher relative abundance of Christensenedilaceae, Aligiphilus and Algoriphagus than CON and 18% CP. ...
65,000 sheep skin cDNA clones were gridded in high density on to nylon membranes and screened for... more 65,000 sheep skin cDNA clones were gridded in high density on to nylon membranes and screened for (CA)n and (GA)n repeat containing clones. 296 dinucleotide repeat-containing clones were identified with ∼85% non-redundancy. Clones were single-pass 5′ sequenced and we compared the Expressed Sequence Tag (EST) sequences to the Swiss-Prot database to ascertain their identity and/or putative function. We then aligned the ESTs against the human genomic sequence to determine the locations of human orthologous sequences. Finally, we developed a subset of polymorphic microsatellite markers and positioned them on the ovine linkage map.
Timing of conceptus growth and attachment to the uterine luminal epithelium is regulated by proge... more Timing of conceptus growth and attachment to the uterine luminal epithelium is regulated by progesterone secretion from the corpus luteum and by expression of progesterone receptor in the uterine epithelia and stroma. Conceptus growth and uterine attachment are temporally associated with the disappearance of progesterone receptors from uterine epithelia. While the loss of progesterone receptor from the endometrial epithelia on day 10 of the oestrous cycle and pregnancy has been well documented, the factors involved with cell specific down-regulation of progesterone receptor are yet to be established. We propose that several progesterone stimulated factors activate nuclear factor kappa B (NF-kB) within the uterine epithelia, which leads to inhibition of progesterone receptor and concomitant stimulation of endometrial genes expressed during early conceptus development. Although oestrogens secreted by pig conceptuses function to establish pregnancy, timing of endometrial exposure to oestrogen is critical. Early oestrogen administration alters the pattern of gene expression through the NF-kB system desynchronising the uterine environment for conceptus implantation resulting in later embryonic loss.
Cathelicidins are an important family of cationic host defense peptides in vertebrates with both ... more Cathelicidins are an important family of cationic host defense peptides in vertebrates with both antimicrobial and immunomodulatory activities. Fowlicidin‐1 and fowlicidin‐2 are two newly identified chicken cathelicidins with potent antibacterial activities. Here we report structural and functional characterization of the putatively mature form of the third chicken cathelicidin, fowlicidin‐3, for exploration of its therapeutic potential. NMR spectroscopy revealed that fowlicidin‐3 comprises 27 amino‐acid residues and adopts a predominantly α‐helical structure extending from residue 9 to 25 with a slight kink induced by a glycine at position 17. It is highly potent against a broad range of Gram‐negative and Gram‐positive bacteria in vitro, including antibiotic‐resistant strains, with minimum inhibitory concentrations in the range 1–2 µm. It kills bacteria quickly, permeabilizing cytoplasmic membranes immediately on coming into contact with them. Unlike many other host defense peptides with antimicrobial activities that are diminished by serum or salt, fowlicidin‐3 retains bacteria‐killing activities in the presence of 50% serum or physiological concentrations of salt. Furthermore, it is capable of suppressing lipopolysaccharide‐induced expression of proinflammatory genes in mouse macrophage RAW264.7 cells, with nearly complete blockage at 10 µm. Fowlicidin‐3 appears to be an excellent candidate for future development as a novel antimicrobial and antisepsis agent, particularly against antibiotic‐resistant pathogens.
It is generally accepted that “temperamental” cattle are more anxious or experience higher stress... more It is generally accepted that “temperamental” cattle are more anxious or experience higher stress, causing differences in intake and performance. The objective of this study was to examine whether temperament affects how steers perform during prolonged water restriction, a chronic stressor. Steers from numerous sources in 4 groups (n = 469) were randomly allocated to 2 weight blocks. Steers were fed ad libitum 3 times a day for 70 d. After a 28 d step-down period, steers were maintained at 50% of normal water allotment for 42 d while feed continued to be offered ad libitum. Individual feed and water intake (WI) were measured daily using an Insentec RIC feeding system. Body weight, exit velocity (EV; measured over 1.5m), and chute score (CS; reported on a 1–4 scale) were measured every 14 d. Lower scores indicate calmer temperament. Due to the study design, DMI, ADG, G:F, and WI were split into 7 periods (d 0–28, 28–70, 0–70, 98–140, 98–112, 112–126, and 126–140). Data were analyzed using the MIXED procedure of SAS where the model included EV, CS, the interaction, and block; group was included as a random effect. Gain, DMI, and G:F d 0–28 were affected by both CS and EV. Slow EV steers had higher DMI than fast EV steers (P < 0.02) during d 28–70 and 0–70. During d 28–70, intermediate CS steers had the highest DMI (P < 0.05). During d 0–70 and 98–140, intermediate CS steers had the highest ADG (P < 0.05). All measures of DMI and WI were higher in the heavy weight block (P < 0.05); ADG and G:F were also higher in the heavy weight block during d 0–70 (P < 0.001). This experiment indicates that there may be performance benefits for steers with intermediate CS during long periods of water restriction.
Reducing dietary crude protein (CP) beyond a certain threshold leads to poor growth performance i... more Reducing dietary crude protein (CP) beyond a certain threshold leads to poor growth performance in pigs; however, the underlying mechanisms are not well understood. Following an adaption period, thirty-seven weaned pigs were weight matched (8.41 ± 0.14 kg), housed individually and randomly assigned into three groups with different dietary CP levels: 24% CP (CON; n = 12), 18% CP (n = 12) and 12% CP (n = 13) for 28 days. The body weight was not different between the CON and 18% CP diets, but 12% CP significantly decreased body weight after day 21. Compared to the CON, pigs fed with 12% CP decreased feed intake day 17 onwards. The 12% CP diet increased the energy expenditure during week 1 compared to the CON. The 12% CP influenced starch and sucrose, nitrogen, and branched-chain amino acids metabolism pathways. The feces of pigs fed with 12% CP were less enriched in Prevotella, but had higher relative abundance of Christensenedilaceae, Aligiphilus and Algoriphagus than CON and 18% CP. ...
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