bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diet selection of sheep: sodium bicarbonate, but not the offering of hay, modifies the effect of urea on diet selection
Authors: James S. M. , Kyriazakis I. , Emmans G. C. , Tolkamp B. J. 
Published: August 2016

AbstractThe hypotheses tested were that the expected preference of sheep for a food with adequate rumen degradable protein (RDP) supplemented with urea would be reduced both by the addition of a buffer (sodium bicarbonate (SB)) and by offering ad libitum access to hay. A control food (C), calculated to be adequate in its ratio of effective RDP to fermentable metabolizable energy (fME), was formulated. Other foods were made by adding 12·5 (U1) or 25 (U2) g urea per kg fresh matter (FM) to C and 20 g SB per kg FM to C, U1and U2. The acid buffering capacity (ABC) of each food was measured in vitro. The experiment consisted of two successive periods, each of 4 weeks. Ninety-eight female, Texel ✕ Greyface sheep were randomly allocated to 14 groups each with seven animals. Groups 1 to 6 were offered one of: C, U2, C + SB, U2+ SB, C with hay or U2with hay throughout the experiment. Groups 7 to 10 were offered the choices of C v. U1or C v. U2, either with or without hay in a change-over design; animals that received hay during period 1 (groups 8 and 10) did not do so during period 2 and vice versa (groups 7 and 9). Groups 11 to 14 (no. = 7) were offered the choices of C v. U1or C v. U2, either with or without SB supplemented to both foods, in a change-over design. Adding either urea, or SB, or both to C had no effects on intake or live-weight gain when offered alone. Both supplements significantly (P 0·001) increased the ABC of food C. Throughout the experiment hay consumption was very low (overall mean: 23 (s.e. 2·5) g hay per sheep day). Offering hay caused no change in the preference for the urea-supplemented foods. Sheep offered the choices C v. U1or C v. U2, with neither hay nor SB, selected 0.466 (s.e. 0·036) and 0.588 (s.e. 0·025) kg/kg total food intake (TFI) of U1and U2respectively. The proportions of the urea-supplemented foods were significantly reduced (P 0.01) by SB supplementation: to 0.348 (s.e.0·045) and 0·406 (s.e.0·059) kg/kg TFI of U1and U2respectively. The effect of SB addition on the diet selection of sheep could be due to its buffering properties. When SB is added to both foods the need for urea to be used as a buffer is reduced with a consequent decrease in the proportion selected as the urea-supplemented food. Effects of diet on buffering may override other diet selection objectives, such as the avoidance of an excess intake of RDP.
Effects of selection for production and maternal diet on maiden dairy heifer fertility
Authors: Pryce J. E. , Simm G. , Robinson J. J. 
Published: August 2016

AbstractThe objectives of this study were to investigate reproductive performance and the influence of maternal environment on reproductive performance in two genetic lines of maiden heifers. These were given food and managed in the same way at the Langhill Dairy Cattle Research Centre. The two genetic lines were established in 1973; one has been selected for high combined yield of fat plus protein (selection line; S) and the other has been maintained at around the UK average for genetic merit of yield of fat plus protein (control line; C). Analysis of the reproductive performance of 988 heifers born between 1981 and 1998 showed that S heifers were poorer (all P < 0·05) than C heifers for all reproductive measures: conception at first service (S: 0·64, s.e. 0·02; C: 0·71, s.e. 0·03), interval between first and last service (S: 18·2 days, s.e. 2·2; C: 13·4 days, s.e. 2·2) and number of services per conception (S: 1·49 services, s.e. 0·06; C: 1·39 services, s.e. 0·06). S heifers were also younger at first service than C heifers (474·9 days v. 480·1 days, s.e. 1·9, for S and C respectively; P • 01). Fertility of service sires may have had some influence on these results, but this could not be investigated here, as S heifers were mated only to high merit bulls and C heifers to average merit bulls. However, within genetic line, the yearly downward trend in the average number of services per conception of heifers was significantly different from zero for the S line, but not the C line. There were no statistically significant relationships between conception rates in maiden heifers and their subsequent reproductive performance in first lactation. The effect of maternal environment on the reproductive performance of daughters as maiden heifers was investigated. There were no statistically significant relationships between daughter reproductive performance and dam parity or the feeding system of the dam (either a high or low level of concentrates). Within the limited range of nutritional status of dams during the periods post calving and in early pregnancy, there was no statistically significant effect of maternal nutrition on daughter reproductive performance.
Effects of rearing regime on body size, reproductive performance and milk production during the first lactation in high genetic merit dairy herd replacements
Authors: Carson A. F. , Dawson L. E. R. , McCoy M. A. , Kilpatrick D. J. , Gordon F. J. 
Published: August 2016

AbstractOne hundred and thirteen high genetic merit Holstein-Friesian heifers were used in a study to determine the effect of rearing regime, in terms of diet offered and target calving weight, on body size, reproductive performance and milk production in high genetic merit heifers. Eighty of the heifers were supplied from 11 commercial farms, the remainder were supplied from the herd at the Agricultural Research Institute of Northern Ireland. The heifers commenced the experiment at 7 weeks of age when they were allocated on the basis of source, live weight and genetic merit to one of four rearing regimes. The target weights at calving were 540 kg (treatment 1) and 620 kg (treatments 2, 3 and 4). Treatment 1 heifers were offered grass silage-based diets during the winter and grass-based diets during the summer. Treatment 2 heifers were offered the same forage base plus additional concentrate supplementation. Treatment 3 heifers were offered a straw/concentrate diet during the winter and grass-based diets during the summer. Treatment 4 heifers received the same diets as treatment 3, except for the first summer period when they remained housed and were offered a straw/concentrate diet. The heifers were mated at 14 months of age and were returned to the 11 source farms one month prior to calving. Heifers reared on treatment 1 had a lower withers height (P < 0·001) and were of a lower condition score (P < 0·001) before calving than heifers reared on treatments 2, 3 and 4. During early lactation (3 months post calving) heifers reared on treatment 1 lost less weight and condition score than the heifers reared on the other treatments. Thus at the end of the first lactation live weights did not differ significantly between the treatments. However, body length remained shorter (P < 0·01) in treatment 1 compared with treatments 2, 3 and 4. First lactation milk yield (305 days) was lower for heifers reared on treatment 1 (7222 l) compared with heifers reared on treatment 2 (8020 l) (P < 0·01), 3 (7956 l) (P < 0·01) and 4 (7901 l) (P < 0·05). Similarly, milk fat plus protein yield was lower (P < 0·05) for heifers reared on treatment 1 (511 kg) compared with treatments 2 (544 kg), 3 (544 kg) and 4 (554 kg). The interval from calving to first recorded oestrus was shorter in treatment 1 compared with treatments 2 and 3 (P < 0·05). There was a tendency (P < 0·10) for heifers reared on treatment 1 to have a shorter calving interval (394 days) compared with treatments 2 (426 days), 3 (435 days) and 4 (458 days). In conclusion increasing the live weight of Holstein-Friesian heifers at first calving from 540 to 620 kg pre-calving increased milk yield proportionally by 0·11 but tended to increase the calving interval. Diet type during the rearing period had no effect on milk fat plus protein yield or reproductive performance.
The effects of graded levels of dietary tannin on the epithelial tissue of the gastro-intestinal tract and liver and kidney masses of Boer goats
Authors: Mbatha K. R. , Downs C. T. , Nsahlai I. V. 
Published: August 2016

AbstractThis study was conducted to determine the effects of different levels of dietary tannin on gastrointestinal tract (GIT) histology and on liver and kidney masses. Five groups of Boer goats were given diets containing 0, 50, 100, 150 and 200 g/kg of tannin for 6 weeks before data collection. Differences in the histopathology of the oesophagus, reticulum, rumen, omasum, abomasum and duodenum were evaluated. Increased dietary tannin levels induced thickening and/or keratinization of epithelial tissue in the reticulum, rumen, omasum and abomasum. Increased tannin levels also resulted in a loss of epithelial cells, erosion of microvilli and shortened villi height in the duodenum, which could impair the absorption of nutrients. Consequently, condensed tannins had a negative effect on the histopathology of the Boer goats.
Comparison of lactational responses of dairy cows in Georgia and Israel to heat load and photoperiod
Authors: Aharoni Y. , Ravagnolo O. , Misztal I. 
Published: August 2016

AbstractThe seasonal effects of heat load and photoperiod on yield and composition of milk from primiparous cows in the course of lactation were studied using test day records from 8968 primiparous cows on 76 farms in Georgia, collected from 1990 through 1997. The effect of prepartum photoperiod on milk production in the subsequent lactation of these cows was also evaluated. These estimated seasonal effects were compared with those estimated for 4728 primiparous cows on 13 farms, and for 1538 multiparous cows on three farms during consecutive lactations in Israel from 1994 through 1996. During lactation, the day length had a positive effect on milk yield and negative effects on fat and protein concentrations in the milk, but the daily change in day length had positive effects on milk yield and fat concentration, and a smaller positive effect on protein concentration. The day length during the prepartum period had negative effects on milk yield and fat and protein concentrations. The heat load during lactation had negative effects on milk yield and fat and protein concentrations. Most of the effects were highly (P < 0·001) significant. There was a very good match between the results obtained for primiparous cows in Georgia and Israel, for the combined effects of heat load and photoperiod during lactation on milk yield and protein and fat concentrations. The match between primiparous and multiparous cows in Israel was better for milk yield and protein concentration than for fat concentration. The estimated effects of pre-partum photoperiod were higher for multiparous cows in Israel than for primiparous cows in either country.
Introgression of genes responsible for disease resistance in a cattle population selected for production: genetic and economic consequences
Authors: van der Waaij E.H. , van Arendonk J.A.M. 
Published: August 2016

AbstractThe genetic and economic consequences of introgression of either one or two genes that explain the complete between-breed difference for disease resistance between donor and recipient breeds were investigated. Four backcross strategies (0, 1, 3 or 7 generations of backcrossing) were compared for four initial breed differences (0·1, 1, 2·5 and 5 phenotypic s.d.) when female reproductive capacity was either high (10 offspring) or lower (four offspring). Selection in donor and recipient populations was for production using a selection index. Genetic comparison was based on production level between the hybrid population, after fixation of the disease resistance alleles, and the donor population. Tor a large initial breed difference and high female reproductive capacity, application of seven generations of backcrossing resulted in the largest genetic difference between donor and hybrid populations. Introgression of one or two genes made no difference to the genetic results. From an economic point of view, optimal number of generations depends on the number of genes involved in the introgression, on the female reproductive capacity and ön the initial breed difference. Seven generations of backcrossing in most cases are too many and none to three generations of backcrossing often is more optimal. Introgression of two genes is economically less attractive, especially in case of low female reproduction capacity.
Carcass and meat quality of Talaverana breed sucking lambs in relation to gender and slaughter weight
Authors: Velasco S. , Lauzurica S. , Cañeque V. , Pérez C. , Huidobro F. , Manzanares C. , Díaz M.T. 
Published: August 2016

AbstractForty-five Talaverana breed sucking lambs of both sexes were slaughtered at 10 and 12 kg live weight in order to study the effect of gender and slaughter weight on carcass, meat and fat traits. Carcass dressing proportions and fatness (by various measures) were higher in females and heavier lambs, which also showed better conformation. Lightness (L*) of the carcass fat was higher in males and heavier lambs. Females and heavier lambs also displayed a greater proportion of fat on dissection, primarily due to a higher percentage of subcutaneous fat tissue. Water-holding capacity was greater in males and in lower-weight lambs. Males presented higher total collagen and lower soluble collagen values than females. In general, a high percentage of short-chain (C12:0 and C14:0) fatty acids, as well as of palmitic acid (C16:0), was observed in the intramuscular fat of the longissimus dorsi muscle, corresponding with an exclusively milk diet.
The nutritive value of extruded and raw peas for growing and finishing pigs
Authors: O’Doherty J.V. , Keady U. 
Published: August 2016

AbstractTwo experiments were conducted to determine the nutritive value of extruded or raw peas (Pisum sativum as an energy and protein supplement for pigs of 33 to 100 kg live weight. Experiment 1 determined the effects of extrusion on the nutrient apparent digestibility of peas when included at 200 g and 400 g/kg in the diet. In experiment 2, performance was determined in individually fed pigs (no. = 70) offered diets ad libitum including a control (no peas, T1), 200 g/kg raw peas (T2), 400 g/kg raw peas (T3), 200 g/kg extruded peas (T4), 400g/kg extruded peas (T5). The peas were extruded at 120°С for 30 s. All diets were formulated to have similar concentrations of digestible energy (DE) and total lysine. There was a significant interaction effect (P < 0·05) between level of peas and extrusion on the digestibility of the organic matter (OM), nitrogen (N), energy and the DE content of the peas. The inclusion of 400 g/kg raw peas led to a lower estimated digestibility of OM (P < 0·001), N (P < 0·001), gross energy (P < 0·05) and DE content (P < 0·05) of the peas compared with the 200 g/kg peas. However, there was no difference (P > 0·05) between the digestibility of the 200 and 400 g/kg peas when the peas were extruded. In experiment 2, there was a significant interaction (P < 0·05) between the level of peas in the diet and extrusion. As the level of raw peas increased from 200 to 400g/kg, growth rate decreased (P < 0·01) and food conversion ratio (FCR) increased (P < 0·01). However, as the level of extruded peas was increased from 200 to 400g/ kg, there was no difference in either growth rate or FCR. It is concluded that extrusion of peas improved the nutrient digestibility and improved overall gain and FCR of the pigs.
Survival of Swedish Landrace and Yorkshire sows in relation to osteochondrosis: a genetic study
Authors: Yazdi M. H. , Lundeheim N. , Rydhmer L. , Ringmar-Cederberg E. , Johansson K. 
Published: August 2016

AbstractA genetic study was carried out to: (1) conduct a genetic analysis of longevity of Swedish Yorkshire sows, (2) study the environmental and genetic factors that influence the presence and severity of osteochondrosis, and (3) investigate the relationship between breeding values for osteochondrosis and longevity of sows. The data for the longevity analyses were extracted from the Swedish litter-recording scheme data bank (Quality Genetics, former Scan Avel HB). After editing original data, records of 9814 Yorkshire sows with 7553 (77%) uncensored and 2261 (23%) censored born 1986 through 1997 were used in the analyses. Litter size at first and last farrowing, age at first farrowing, backfat thickness, daily gain and weight at completion of performance test (~170 days) were included as fixed effects in all analyses. The combination of herd-year effect was treated as fixed or random, time-independent or time-dependent in different analyses. Sire effect was considered as the source of genetic variation and thus a sire model was used. The analyses of osteochondrosis were based on information on 14 388 Landrace and 14 458 Yorkshire pigs from the Swedish pig progeny-testing scheme, recorded from 1987 through 1997. The birth herd and the combination of sex, testing station, year and month for start of test were included as fixed effects in the statistical model. Variance and covariance components for osteochondrosis recorded at elbow and knee joints were estimated in a bivariate animal model by the restricted maximum likelihood method within each breed. In the survival analyses (Yorkshire sows), the fixed effects of herd-year (when it was treated as fixed effect), litter size at first and at last farrowing, age at first farrowing, backfat and gain at completion of performance test were highly significant (P < 0·01). Herd-year combination was the major cause of variation for risk of culling, compared with other fixed effects. The risk of being culled at a certain time decreased as the litter size at first and at last farrowing, or backfat of the gilt at completion of performance test increased. With increasing age at first farrowing, the risk of being culled at a certain time increased. Heritability in the original scale for longevity ranged from 0·21 to 0·31. The results for osteochondrosis showed that the combined effect of sex-testing station-year and month of start of test was highly significant (P < 0·01). Estimates of heritabilities for osteochondrosis score were similar for both Landrace and Yorkshire breeds and was, on average, 0·21. The correlations between breeding values for longevity and osteochondrosis were low (on average 0·07, adjusted for genetic trends) but were significant (P < 0·01) and in a favourable direction: higher osteochondrosis load associated with higher risk of being culled.
Effects of cow families on production traits in dairy cattle
Authors: Roughsedge T. , Visscher P. M. , Brotherstone S. 
Published: August 2016

AbstractThe components of phenotypic variance attributable to maternal lineage for production traits of the UK Holstein Friesian dairy population were estimated. First lactation production records of 55 230 cows calving between 1996-1998 in the UK Holstein Friesian population were used in the analysis. Maternal pedigree records were traced back to 1960 to establish maternal lineages. The tracing resulted in 36 320 cows being assigned to 11 786 cow families with more than one cow per maternal lineage. Using test day records it was possible to explore aspects of the lactation curve in terms of persistency and different periods of production. The traits analysed were 305-day milk yield and composition traits, the first three milk yield tests of lactation and two measures of persistency. A contemporary record design was used to minimize pair-wise additive direct genetic relationships between cows within a maternal lineage and to remove both the effect of heterogeneous variance over time and the complications of permanent environment effects. No significant component of variance attributable to maternal lineage was found for yield traits. When data were restricted to maternal lineages with five or more records, persistency, as a ratio of cumulative yield in the last third to that in the first third of a 300-day lactation, was estimated to have a 4·4% component due to maternal lineage variance significant at the 5% level. The study also investigated the preferential treatment of cow families. Some evidence of maternal lineage×herd interaction was found.
Increasing food intake in late gestation improved sow condition throughout lactation but did not affect piglet viability or growth rate
Authors: Miller H. M. , Foxcroft G. R. , Aherne F. X. 
Published: August 2016

AbstractIncreasing sow food intake in late gestation prevents loss of sow fatness prior to farrowing. However, this may result in reduced food intake and greater overall fat loss during lactation and has also been associated with increased incidence of agalactia. In this experiment 78 Camborough sows (parities 1 to 3) were given food at one of two levels: either 1·15×maintenance energy (normal-N sows, 2·3 (s.e. 0·03) kg/day) or 2·00×maintenance energy (high-H sows, 3·9 (s.e. 0·04) kg/day) from day 100 of gestation until farrowing. Lactation food intake, changes in sow live weight and backfat thickness and piglet growth rates were then measured. Diet digestibility in early lactation was measured using a chromium III oxide marker in the food. There was no change in backfat thickness in late gestation in H sows (0·2 (s.e. 0·25) mm), whereas N sows lost backfat during this period (1·6 (s.e. 0·23) mm,P<; 0·001). There was no difference in lactation food intake between the two groups (6·5 (s.e. 0·13) kg/day) and differences in backfat thickness at parturition were maintained through to weaning. H sows did not show increased incidence of agalactia compared with N sows. There was no difference in diet digestibility between the two treatment groups. Food intake level in late gestation did not affect piglet birth weights, growth rates or mortality. It is concluded that the main benefit of increasing sow food intake in late gestation was to reduce sow backfat loss during the reproductive cycle.
Growth hormone response to infusion of somatostatin in dairy calves: testing its use as a diagnostic tool for genetic merit
Authors: Wiener P. , Angus K. D. , McCullough E. , Woolliams J. A. 
Published: August 2016

AbstractThis paper describes a two-part study evaluating the use of growth hormone (GH) response to infusions of somatostatin (SRIF) and GH-releasing factor (GRF) as an indicator of genetic merit in dairy cattle. The first part of the study involved the development of a standard test procedure. This was achieved in two sub-trials, the first testing three SRIF doses, 0·6, 3·0 and 15 µg/kg per h, given over an infusion length of 3 h. The second involved infusing 3·0 μg/kg per h SRIF for either 20 min, 1 h or 3 h. The GH response was measured in serum during the infusion and for 2 h following cessation, during which time a rebound response in GH occurred. As a consequence of these trials, a total of 40 British Friesian calves from two lines genetically divergent for yield traits were infused with 3·0 μg/kg per h for a period of 1 h and at the end of the infusion given 0·1 μg/kg GRF. Five hours later, GRF was administered without SRIF. The protocol was repeated on 2 days consecutively. Results suggested that calves of high merit had lower SRIF-induced baselines than their low-line contemporaries. There were no differences in the GH concentrations immediately following GRF administration, either with or without SRIF. The results from this trial, together with previously published work, indicated that calves selected for high milk fat plus milk protein production may be more sensitive to SRIF such that GH is regulated by lower concentrations of SRIF. However, the practical use of GH response to SRIF as an indicator of genetic merit for dairy cattle may be limited because of logistical difficulties in implementation.