bluuebunny/crossref_metadata_2025_split huggingface dataset:
The requirements of weaned piglets for a training period prior to a choice-feeding regime
Authors: Dalby J. A. , Forbes J. M. , Varley M. A. , Jagger S. 
Published: September 2010

AbstractThe requirement for a training period prior to a choice feeding regime was assessed using 36 weaned piglets whose initial live weight was 6·2 (s.d. 1·21) kg. Two foods (H and L) were offeredad libitumas the choice and these were similar in energy but differed in crude protein (CP) concentration (291 g/kg and 155 g/kg fresh matter respectively). The pigs ivere subjected to one of three training treatments: treatment ALTERNATE allowed piglets the two foods separately on alternate days for 6 days, followed by a free choice of the two foods; treatment THREE allowed 3 days of one food followed by 3 days of the other prior to the free choice; treatment CHOICE gave the animals free choice immediately. Piglets on a fourth treatment, CONTROL, were given a single food M (242 g CP per kg fresh food) as a control. Weight gain (0·60, 0·59, 0·59 and 0·61 (s.e. 0·005) kg/day) and food intake (0·776, 0·752, 0·771 and 0·747 (s.e. 0·010) kg/day) did not differ significantly between treatments ALTERNATE, THREE, CHOICE and CONTROL respectively in the 19-day post-training period. A significant difference was seen in the protein consumption (0·145, 0·150, 0·139 and 0·177 (s.e. 0·005) kg/day). This together with a tendency for the proportion of food H selected to decline as the growth period progressed, indicated that newly weaned piglets are capable of regulating their protein intake when offered a free choice of two foods differing in their CP concentration, without a necessity for an initial training period.
Ontogenic study of insulin-like growth factor-1 and growth hormone receptor mRNA expression in porcine liver and skeletal muscle
Authors: Brameld J. M. , Weller P. A. , Pell J. M. , Buttery P. J. , Gilmour R. S. 
Published: September 2010

AbstractThe growth hormone-insulin-like growth factor (GH-IGF) axis is involved in the control of postnatal growth in all animals studied to date. At birth, blood levels of IGF-1 are low, although levels of GH are high. Thus a switching occurs during the postnatal period, which involves an increase in liver GH-receptors (GHR). This study investigates the changes in serum IGF-1 and IGF-1 and GHR mRNA in liver and skeletal muscle of growing pigs. The period from birth to 20 days of age showed a gradual increase in both IGF-1 and GHR mRNA expression by the liver, thus accounting for the gradual increase in serum IGF-1. The IGF-1 mRNA expressed was found to be predominantly class 1 transcripts with very few class 2 transcripts. There was a plateau of liver IGF-1 mRNA levels after 20 days and up to 140 days, even though the expression of GHR mRNA continued to increase. The levels of expression of the two genes were found to correlate in the first 20-day period (r = 0·76,P< 0·005), but not in the later period (r = 0·44,P> 0·05).Levels of expression of both genes in the LD muscle were highly variable, with no age related changes being observed. However, a significant negative correlation of expression of the two genes was observed (R = 0·60,P< 0·001), with the correlation still being significant in the two age periods.The data are consistent with a likely initial dependence for postnatal growth upon GH-stimulated IGF-1 mRNA expression by the liver, up to 20 days of age. After this time, hepatic expression of IGF-1 mRNA reaches a plateau, even though the serum IGF-1 and hepatic GHR mRNA levels continue to rise. A possible explanation for this could be an increase in either turn-over or stability of IGF-1 mRNA, giving rise to increased levels of peptide with no apparent change in mRNA level. Another possibility is that an increased expression/production of the IGF-binding proteins leads to an increase in the half-life of the peptide in the circulation.
Changes in the composition of plasma very low density lipoprotein during pregnancy and lactation in genetic lines of pigs
Authors: Wright M. M. , Lean I. J. , Herrera E. , Dodds P. F. 
Published: September 2010

AbstractPlasma very low density lipoproteins (VLDL) of gilts were separated into two sub fractions according to their affinity for heparin. The proportion of VLDL present as subfraction 2 (higher affinity for heparin) varied, according to the genetic line of the pigs, between 0·21 and 0·78 in virgin gilts. The proportions were related to the variation in piglet survival in the same nine genetic lines by a quadratic equation, which predicted that greater than 90% survival to weaning was to be found in piglets born to gilts having between about 0·3 and 0·7 of their VLDL as subfraction 2. This observation suggests a simple measurement that could be used in the selection of sows for a breeding programme. The proportion of subfraction 2 fell throughout pregnancy in each of three genetic lines measured and only returned to pre-pregnant values after weaning: these changes did not correlate with the changes in the lipid composition of plasma VLDL measured during pregnancy and lactation. The findings suggest a role for the VLDL subfractions in controlling the nutrition of the neonatal pig.
Relationship between puberty in heifers and the cessation of luteal activity after nutritional restriction
Authors: Vizcarra J. A. , Wettemann R. P. , Bishop D. K. 
Published: September 2010

AbstractThe relationship between puberty and the cessation of luteal activity after nutritional restriction was evaluated in 15 Angus × Hereford heifers. Heifers attained puberty at a body weight of 297 (s.e. 6) kg and a body condition score (BCS) of 5·5 (s.e. 0·1) on a scale of 1 (emaciated) to 9 (obese). After 154 (s.e. 16) days of nutritional restriction, heifers became anoestrus at a weight of 273 (s.e. 8) kg and a BCS of 3·0 (s.e. 0·2). The Spearman's rank correlation coefficient between date of-puberty and date of cessation of luteal activity was (r = –0·49; P < 0·06). This indicates that the heifers that attained puberty first were the last to cease luteal activity during nutritional restriction.
The effect of sward height on grazing behaviour and herbage intake of three sizes of Charolais cattle grazing cocksfoot (Dactylis glomerata) swards
Authors: Cazcarra R. Ferrer , Petit M. , D'hour P. 
Published: September 2010

AbstractMature non-lactating cows, 18-month-old heifersand7-month-oldfemale calves of the Charolais breed (eight animals of each age) were strip-grazedon short (S, sward surface height: 7·5 cm), medium (M,10·2 cm) and tall (T, 21·1 cm) cocksfoot (Dactylis glomerata) swards at a daily herbage allowance of 40 g dry matter per kg live weight over three 15-day experimental periods. The swards were leafy regrowths of 1 (S), 2 (M)and 3·5 (T)weeks of age. Herbage intake was estimated by the n-alkane method, and grazing behaviour was recorded visually.Intakes per kg live weight of calves and heifers were higher than those of cows on all swards(P < 0·01). Calves tended to maintain intake, whereas cows and heifers reduced their intake as sward height decreased. Bite weight decreased linearly with sward height, this decrease being greater for larger animals (P < 0·001). As sward height decreased, the scaling factor of bite weight to live weight decreased. Biting rates increased as sward height decreased (P < 0·001) and were lower in calves than in older cattle (P < 0·001). Calves had lower intake rates per kg live weight than cows in T swards, and the reverse was true in S swards (P < 0·001). Younger cattle always grazed longer than cows, but differences were reduced as sward height decreased (P < 0·01). Cows and heifers wereunable to increase their grazing time sufficiently to compensate for lower intake rates in S and M swards, resulting in reduced herbage intakes. Faecal markers and grazing behaviour suggested a greater selectivity by calves compared with older cattle.
The effects on milk yield and composition of incorporating lactose into the diet of dairy cows given protected fat
Authors: Garnsworthy P. C. 
Published: September 2010

AbstractTwenty-eight Holstein/Friesian dairy cows were divided into four groups of seven. From weeks 4 to 15 of lactation they were given a basal diet consisting of 8 kg hay, 2 kg sugar-beet feed and 2 kg grass nuts, together with a concentrate allowance of 8 kg/day. Concentrates for group A were based on cereals and soya (control). Concentrate B contained 60 g protected fat supplement per kg; concentrate C contained 100 g lactose per kg; concentrate D contained 60 g fat supplement and 100 g lactose per kg. Milk yields were 24·6, 27·7, 25·6 and 26·5 kg/day and milk protein concentrations were 32·3, 30·7, 32·7 and 31·9 g/kg for groups A, B, C and D respectively. The effect of fat supplementation on milk yield and protein concentration was significant (P < 0·05) but the effect of lactose was not significant. Milk fat concentration was not significantly affected by treatment. It is concluded that lactose can partially alleviate the depression in milk protein concentration often observed when cows are given protected fat.
Keeping growing cattle outside during winter: behaviour, production and climatic demand
Authors: Redbo I. , Mossberg I. , Ehrlemark A. , Ståhl-Högberg M. 
Published: September 2010

AbstractKeeping cattle inside on concrete slatted floors can be detrimental to their health and behaviour and is also costly. Therefore, 22 steers of the Swedish Red and White Dairy breed were used to investigate the effect of wintering outdoors on growing cattle. The steers had a mean weight of 310 kg at the onset of the study. During winter, 11 ‘indoor’ steers were housed in pens with concrete slatted floors and 11 ‘outdoor’ steers were kept in a field with access to a shelter and trees. From the end of April until slaughter in September, both groups grazed together. During winter, all steers were given clover silagead libitum. They were weighed every month. The behaviour of the outdoor steers was recorded from November to the end of March. Outdoor temperature, wind speed and solar radiation were measured continuously. A heated model was used in order to calculate the climatic energy demand. The steers were never observed to shiver. They were not observed to use the shelter during daytime. The most frequently observed behaviour was ‘eating’, followed by ‘standing’. The lower the temperature, the more time the steers were observed lying down (P < 0·01). ‘Moving’ increased with increasing temperature (P < 0·05) as well as with increasing wind speed (P < 0·01). During the grazing period following the experiment, the former outdoor steers grew significantly (P < 0·05) better than the former indoor steers. However, there was no significant difference in overall growth rate from start to slaughter. This study suggests that the winter climate in this part of Sweden (latitude 60°N) did not affect in a negative way the welfare or the growth rate of steers kept outdoors.
Correlation of serum GH and IGF-1 with satellite cell responsiveness in Targhee rams
Authors: Dodson M. V. , Hossner K. L. , Vierck J. L. , Mathison B. , Krabbenhoft E. 
Published: September 2010

AbstractThis study was performed to assess the relationship between serum growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels, slaughter weight, and myogenic satellite cell growth kinetics of Targhee rams. Serum was collected from 19 rams at 15-min intervals over a period of 4h. Radioimmunoassays of serum samples for GH revealed considerable variation (within individual rams) over the sampling period, with mean values ranging from 0·63 to 4·88 μg/l (mean overall 2·3 (s.e. 0·33) μg/l; no. = 19). There was no significant correlation between GH levels and slaughter weight (r = −0·11; P > 0·05) at 155 (s.e. 1·08) days. Serum IGF-1 levels of (individual) rams were invariant over the sampling period, with individual means ranging from 62 to 233 μg/l (mean overall of 117 (s.e. 45·6) ugll; no. = 19). IGF-1 was not strongly correlated with slaughter weight (r = +0·35; P > 0·05). Satellite cells were isolated from the left m. semimembranosus of all rams at slaughter and grown in culture to evaluate proliferation amount and differentiation extent. The correlations between serum GH levels and satellite cell proliferation and differentiation in vitro were r = −0·53 (P < 0·05) and r = −0·52 (P < 0·05), respectively. Serum IGF-1 showed no significant correlations to proliferation (r = +0·07; P > 0·05) or to differentiation (r = −0·07; P > 0·05) of the satellite cells. These data suggest that serum GH levels in Targhee rams may not reflect muscle growth potential if correlated to body weight of 155 days. Furthermore, as IGF-1 was not correlated significantly with slaughter weight or to variables of satellite cell proliferation and differentiation, another mode of satellite cell regulation (possibly paracrine controllers) is more likely at play to coordinate the satellite cell involvement in muscle growth in Targhee rams at 155 days.
Effect of progesterone priming on gonadotropin secretion and luteal function in GnRH-treated seasonally anoestrous ewes
Authors: Haresign W. , Basiouni G. F. , Khalid M. 
Published: September 2010

AbstractThe main objective of the experiment was to investigate the mechanism by which progesterone priming eliminates defective luteal function in anoestrous ewes induced to ovulate with GnRH. Animals in group 1 (no. = 10) were primed with a single i.m. injection of progesterone in corn oil 3 days before the start of GnRH treatment, while ewes in group 2 (no. = 10) received corn oil alone and served as untreated controls. Ewes in group 3 (no. = 10), which served as positive controls, were treated with an intra-vaginal progestagen sponge for 7 days, and this was removed just before the start of GnRH treatment. Ewes in all three groups were induced to ovulate by administration of 2-h injections of GnRH (250 ng per injection) for 54 h. Frequent blood samples for LH, FSH and progesterone analysis were taken around the time of both progesterone injection and GnRH treatment, as well as daily thereafter to monitor luteal function, and laparoscopy was performed 3 and 7 days after GnRH treatment.The incidence of ovulation was similar for all the three groups (8/10, 7/10 and 9/10 for groups 1, 2 and 3 respectively). Hoioever, both laparoscopic examination and plasma progesterone concentrations revealed that the incidence of normal luteal function was significantly higher in progesterone-primed animals group 1:7/8; group 3:9/9) compared ivith controls (group 2:0/7), P < 0-05) with no difference between groups 1 and 3. Injection of progesterone on day −3 significantly suppressed mean LH concentrations (P < 0·05), but mean FSH concentrations were not altered. However, there were no significant differences between groups in LH and FSH concentrations over the period of GnRH treatment, nor in the timing, duration and height of pre-ovulatory LH and FSH surges. These results suggest that progesterone priming may eliminate defective luteal function either by changing LH concentrations at the time of progesterone administration or through mechanisms not involving gonadotropin secretion.
Effects of dry sow housing conditions on muscle weight and bone strength
Authors: Marchant J. N. , Broom D. M. 
Published: September 2010

AbstractConfinement has been shown to affect bone strenth in poultry but this weakness has not been documented in other species housed in confinement. The objectives of this experiment were to compare muscle weight and bone strength in non-pregnant sows, of similar age and parity, housed throughout eight or nine pregnancies in two different dry sow systems: (1) individually in stalls and (2) communally in a large group. Following slaughter, the left thoracic and pelvic limbs were dissected and 14 locomotor muscles removed and c. ???lied. A proportional muscle weight was then calculated by dividing individual muscle weight (g) by total body weight (kg). Where there were significant differences, stall-housed sows had lower absolute and proportional muscle weights than group-housed sows. The left humerus and femur were also removed. The bones were broken by a three-point bend test using an Instron Universal Tester. Both bones from stall-housed sows had breaking strengths that were about two-thirds those of group-housed sows. The results indicate that confinement of sows, with a consequent lack of exercise, results in reduction of muscle weight and considerable reduction of bone strength.
Villous height and crypt depth in piglets in response to increases in the intake of cows' milk after weaning
Authors: Pluske J. R. , Williams I. H. , Aherne F. X. 
Published: September 2010

AbstractThe hypothesis tested in this experiment was that the structure and function of the small intestine of piglets given a milk liquid diet after weaning depends on their level of energy intake. At weaning (28 days), 42 piglets were allocated to one of five treatments: (1) control group killed at weaning; (2) piglets offered a dry starter dietad libitum; (3) piglets given cow's fresh milk at maintenance energy intake (Ma); (4) piglets given cow's fresh milk at 2-5 Ma; and (5) piglets given cow's fresh milkad libitum. On the 5th day all piglets were killed and samples of gut were taken for histological and biochemical examination. Piglets given milkad libitumgrew faster (P < 0·001) than piglets on all other treatments. Piglets offered the dry starter diet ingested similar quantities of dry matter and energy, and grew at the same rate as piglets given cows' milk at 2·5 Ma. As predicted, piglets given milk at maintenance energy intake grew slower (P < 0·001) and consumed less food (P < 0·001) than piglets in all other treatments. For piglets given both cows' fresh milk and the dry starter diet, there were significant linear relationships (r = 0·72 to 0·82,P< 0·05) between villous height and crypt depth with dry matter (energy) intake after weaning. In turn, mean villous height in both milk-fed and starter-fed piglets was significantly correlated (r = 0·68 to 0·79,P< 0·05) to empty body-weight gain in the first 5 days after weaning. Estimates of digestive enzyme activity and absorptive capacity of the gut did not corroborate the large differences seen between treatments in villous height and crypt depth, and possible reasons are discussed. These data illustrate the interdependence between voluntary food intake and mucosal architecture in determining piglet performance after weaning.
Feeding level and oral stereotypies in dairy cows
Authors: Redbo I. , Emanuelson M. , Lundberg K. , Oredsson N. 
Published: September 2010

AbstractThe aim of the present study was to investigate the effect of feeding strategy on the performance of oral stereotypies, such as tongue-rolling and bar-biting, and other behaviours in lactating dairy cows. Thirty–seven cows of the Swedish Red and Wliite breed were randomly assigned into three treatments with different feeding strategies. Cows in treatment (AL) were given food ad libitum during the whole experimental period, which lasted from weeks 3 to 26 post partum. The second group (AL–R) was given food ad libitum during weeks 3 to 14 post partum, thereafter they were given food at a restricted level. The third group (R) was given food at a restricted level during the whole experiment period. All cows were offered a total mixed ration consisting of 650 g concentrate and 350 g forage per kg twice a day and their individual daily food intakes were registered. Behavioural recordings were made for 4 h on a fixed day every 2nd week, where each individual cow was observed every 2nd minute.During the complete experimental period, 27 out of the 37 cows showed stereotypies; 13 cows in group R, 10 in group AL–R and four in the AL group. The proportions of cows showing stereotypies were not independent of feeding treatment within the respective periods (P < 0·01). The stereotypy levels, counted as the mean frequency of recordings per treatment period, increased significantly between period 1 (lactation weeks 3 to 14) and period 2 (weeks 17 to 26) in group AL–R (P < 0·01) and in group R(P < 0·01), but not in the AL group. In period 2 the R cows had significantly higher stereotypy levels than the cows in the AL–R group (P < 0·01). Group R decreased the time spent eating between the periods (P < 0·001), with the same tendency in group AL–R. The AL group had longer eating time in period 2 than the AL–R (P < 0–001) and the R (P < 0·001) cows. The AL cows had a higher frequency of rumination than the other treatments in period 2 (P < 0·01). Both the AL–R and the R cows increased their activity levels between the periods (P < 0·001 for both). There were also differences between treatments in period 2, where the AL cows were less active than the AL–R (P < 0·05) and the R cows (P < 0·01).It is concluded that oral stereotypies in dairy cows are highly affected by feeding strategy, where restrictive feeding of a mixed food induces significant increases of stereotypies. The results of this investigation clearly indicate that restricted feeding of a diet with high levels of concentrate has a negative effect on the well being of lactating cows.
The influence of day length and temperature on food intake and growth rate of bulls given concentrate or grass silage ad libitum in two housing systems
Authors: Mossberg I. , Jönsson H. 
Published: September 2010

AbstractIn order to study the effect of day length and temperature on performance, data from 495 growing, non-castrated bulls of the Swedish Red and White breed were analysed. Groups of 11 bulls were housed in either an insulated building in pens having slatted floors or in an uninsulated building with pens having both a deep straw bed and a concrete floor. The majority of the bulls (330) were given a concentrate diet ad libitum, while the remainder (165) were given grass silage ad libitum supplemented with concentrate. Energy intake, live-weight gain, housing temperature, day length and change in day length were calculated as 14-day period means for the two housing systems. Regression analyses showed that live-weight gain was associated with increasing day length in bulls on both feeding treatments. For bulls given concentrate ad libitum, metabolizable energy intake was associated with increasing day length. The intake of heavier animals was more influenced by day length than that of those which were lighter. The seasonal influence on daily energy intake in bulls given silage did not show the same pattern as for bulls given concentrate ad libitum. The intake was highest in June and lowest in December for the bulls given concentrate but for the bulls given silage it was highest in August, September and October and lowest in March and April. This was due to the varying quality of the grass silage over the year. No effect or very little effect of temperature or housing system on energy intake or on weight gain was found.