Relevance of ovarian follicular development to the seasonal impairment of fertility in weaned sows

A field study was conducted to estimate seasonal differences in follicular development in weaned sows and to evaluate the implication of these differences on seasonal infertility. A total of 110 sows were selected at weaning during winter–spring (WS, n = 58) and summer–autumn (SA, n = 52). Ovaries were scanned once daily from weaning to the onset of oestrus and twice daily from then until ovulation. Six sows during WS were removed from study for not showing growing follicles at weaning. Oestrus was evaluated twice daily from day 1 after weaning to day 14 post-weaning. One of 52 (1.9%) sows in WS and 9/52 (17.3%) in SA showed no signs of oestrus within 14 days of weaning (P < 0.05). The diameters of the follicles at weaning, at the onset of oestrus and just before ovulation were smaller (P < 0.01) in SA sows than in WS sows. There were fewer follicles in SA sows than in WS sows just before ovulation (P < 0.05). Fifty of 51 (98.0%) sows in WS and 31/43 (72.1%) sows in SA experienced a weaning-to-oestrus interval (WOI) of 3–6 days (P < 0.05). Fifty-one of 52 (98.1%) sows in WS and 43/52 (82.7%) sows in SA were inseminated; the percentage of pregnant sows that failed to farrow was lower in WS (1/51, 2.0%) than in SA (5/43, 11.6%; P < 0.05). The percentage of farrowed sows was greater in WS (46/51, 90.2%) than in SA (32/43, 74.4%; P < 0.05). Sows in WS had on average 1.5 more piglets than sows in SA (P < 0.05). Sows with a WOI of 3–6 days had lower rates of pregnancy losses (P < 0.05) and higher farrowing percentages (P < 0.01) than those with a WOI > 6 days, irrespective of season.     

Effect of Lactation Diet Fat Level on Sow and Litter Performance

The primary objective of this study was to determine the effects of supplemental dietary fat during lactation on sow BW, sow backfat thickness, sow feed consumption, litter size, and pig growth rate. Dietary treatments included 0, 3, 6, and 9% supplemental low acid yellow fat in a traditional corn-soybean meal basal lactation diet. A total of 160 Landrace and crossbred sows (approximately 40 per treatment) were included in the study. Sows fed 3 and 6% supplemental fat had greater (P<0.10) average backfat thickness at weaning. Sow weight change and feed consumption were inconsistent among dietary fat levels. Dietary fat level during lactation did not affect number of pigs born alive or number of stillborns. However, the 9% fat level was associated with more mummified pigs at birth. Number of pigs weaned was greater for the 0% supplemental fat than for the 9% fat level. The largest average pig weights at 21 (5.8±0.29 kg) and 28 (7.48±0.38) d of age were those from sows fed the 3% added fat diet. Sows with ≤25.4 mm backfat at farrowing had more pigs born alive (P<0.05), had less backfat at 21 and 28 d of lactation (P<0.05), and consumed more feed during wk 2 and 3 of lactation. Of all sows fed the control diet, sows with >25.4 mm backfat at farrowing consistently had heavier pigs throughout the lactation phase (P<0.05). Backfat loss during lactation was lower (P<0.05) for sows with ≤25.4 mm at farrowing within all dietary treatments. Consistent significant differences were not observed in sow weight loss or feed consumption between low and high backfat sows for each dietary treatment. Sow backfat loss during lactation is dependent on body condition at farrowing, in that, fatter sows at farrowing have greater backfat loss during lactation. Sows with ≤25.4 mm of backfat at farrowing responded to added dietary fat treatments and produced heavier pigs throughout the lactation period.     

Supplementing Guinea grass with fresh sweet potato foliage for milk production by Bunaji and N'Dama cows in early lactation

Forage from three sweet potato cultivars (A = TIS-87/0087; B = TIS-8164; C = TIS-2532.OP.1.13 at 30% daily dry matter intake), dried brewers' grains (DBG) and cottonseed meal (CSM) each at 2.5 kg were supplemented to Guinea grass (GG) to form four diets: Diet A = GG + TIS-87/0087; Diet B = GG + TIS-8164; Diet C = GG + TIS-2532.OP.1.13, and Diet D = GG + DBG + CSM (as control). Treatments were assigned as 4 × 4 Latin squares design over 60 days (10-day adaptation and 5-day sampling) using Bunaji and N'Dama cows in early lactation. The 48-h rumen dry matter (DM) degradation ranged (P < 0.01) from 407 g kg^? 1 DM for GG to 791 g kg^? 1 DM for sweet potato cultivar TIS-87/0087. Bunaji dry matter intake varied (P < 0.05) between 7.1 kg day^? 1 in Diet B and 8.9 kg day^? 1 in Diet D, but was similar (P > 0.05) among diets for the N'Dama cows. The metabolisable energy (ME) intakes were higher for Diet D although, it recorded the least efficiency of ME utilization for milk production. Milk yields were significantly (P < 0.01) higher in the Bunaji than the N'Dama cows, which is typical of their true breed differences. Total solids, ash, protein, fat, and sugar contents of the milk were similar among diets for both cow breeds, except Bunaji ash contents that ranged (P < 0.05) from 0.77 g 100 g^? 1 for Diet B to 0.83 g 100 g^? 1 for Diet D. The results suggest that sweet potato forage could be utilized as whole or partial replacement for DBG and CSM to save cost under smallholder farming systems.     

High occurrence of multi-antimicrobial resistance in Staphylococcus intermedius isolates from healthy and diseased dogs and domesticated pigeons

Staphylococcus intermedius isolates (n = 106), including 44 dog isolates and 62 pigeon isolates, were examined for their susceptibility to ampicillin, cephalexin, erythromycin, gentamicin, kanamycin, lincomycin, norfloxacin, oxacillin, tetracycline, and vancomycin by standard disk-diffusion test. The frequencies of resistance to ampicillin, kanamycin, and tetracycline were significantly higher in dog isolates than pigeon isolates (95.5% vs. 0%, 31.8% vs. 0%, and 45.5% vs. 9.7%, respectively; P < 0.01). Antimicrobial resistance patterns of dog isolates and pigeon isolates were categorized respectively into nine and five distinct profiles. Significantly higher occurrence of resistance to two or more antimicrobials was observed in dog isolates than pigeon isolates (54.5% vs. 12.9%; P < 0.01) and also in domesticated pigeon isolates than non-domesticated pigeon isolates (53.3% vs. 0%; P < 0.01).     

The effect of sea transport from Ireland to the Lebanon on inflammatory,adrenocortical, metabolic and behavioural responses of bulls

The objective was to investigate the effect of sea transport on the physiological, behavioural and performance responses of bulls. One-hundred and eleven bulls (mean body weight (standard error of the mean) 429 (5.7 kg)) were randomly assigned to one of three treatments; control (C; n = 54) bulls were housed in 6 pens at Teagasc, Grange Research Centre at a stocking density of (1), 1.7 m²/head (C1.7; 3 pens) and (2), 3.4 m²/head (C3.4; 3 pens) and (3), transported (T) bulls (n = 57) were penned at a space allowance of 1.7 m²/head (6 pens) and allocated to one of five decks on the shipping vessel. C and T bulls were subjected to the same live weight (d −2), blood sampling and rectal temperature (d −1) measurements pre-transport and on d 3, d 6, d 9 and d 11 of the study. T bulls had greater (P < 0.05) live weight gain (+4.4%) compared with C1.7 bulls (−2.0%) and C3.4 (+0.13%)). Time spent lying was greater (P < 0.05) among C1.7 and C3.4 bulls (9.9% and 53.3%, respectively) compared with T bulls (45.8%). Rectal body temperature was not different (P > 0.05) among treatment groups throughout the study. At d 11, neutrophil % was greater (P < 0.05) in transported bulls on decks 1, 2, 4 and 5 compared with C1.7 and C3.4 treatments. Plasma cortisol concentrations were not different (P > 0.05) between control and transported bulls. Plasma creatine kinase (CK) activity was lower (P < 0.05) among C3.4 and T bulls on decks 2, 3, 4 and 5 compared with d 3 values. In conclusion, the welfare of bulls transported by sea on the sea journey was not adversely affected. Housing control bulls at a reduced space allowance (1.7 m²) had a negative effect on live weight gain.     

Age and Body Condition of Goats Influence Consumption of Juniper and Monoterpene-Treated Feed

Redberry juniper (Juniperus pinchotii Sudworth) is an invasive, evergreen tree that is rapidly expanding throughout western and central Texas. Goats will consume some juniper on rangelands; however, intake is limited. The objective of our research was to determine how the age and body condition of goats influence their consumption of juniper and an artificial feed containing 4 monoterpenes. Two separate experiments were conducted. Experiment 1 examined the intake of redberry juniper foliage and used 39 goats either young (2 yr) or mature (> 6 yr). One-half of each age group was fed appropriate basal rations to reach either a high (HBC) or low body condition (LBC). Goats in LBC ate more (P < 0.01, 8.6 g · kg⁻¹ body weight [BW] ± 0.7 SE) juniper than those in HBC (2.3 g · kg⁻¹ BW ± 0.3 SE), and young animals consumed more (P < 0.05, 7.2 g · kg⁻¹ BW ± 0.7 SE) juniper than mature goats (3.9 g · kg⁻¹ BW ± 0.5 SE) across body condition treatments. In experiment 2, 36 goats, either young (2 yr) or mature (> 6 yr) and in either HBC or LBC, were offered a synthetic ration treated with 20.8 g · kg⁻¹ of 4 monoterpenes found in redberry juniper. Goats in LBC ate more (P < 0.01, 25.3 g · kg⁻¹ BW ± 1.0 SE) of the terpene-treated feed than those in HBC (17.5 g · kg⁻¹ BW ± 0.7 SE), and young animals ate more (P < 0.05, 22.5 g · kg⁻¹ BW ± 0.8 SE) than mature goats (20.3 g · kg⁻¹ BW ± 0.8 SE) across body condition treatments. Total intake as a proportion of body weight was also affected by body condition. Age and body condition are important factors that influence intake of chemically defended plants. A better understanding of how these attributes affect diet selection will aid livestock producers in improving grazing management.     

Iron metabolism in hamsters experimentally infected with Leptospira interrogans serovar Pomona: Influence on disease pathogenesis

The aim of this study was to analyze the classic iron markers associated to the storage process in hamsters experimentally infected by Leptospira interrogans serovar Pomona. Four groups with six hamsters each were used; two were negative controls (C7 and C14) and two were composed by infected animals (T7 and T14). Blood samples were collected on the seventh (C7 and T7) and fourteenth days (C14 and T14) post-inoculation. Iron availability was determined in sera samples through the assessment of iron, ferritin, transferrin, and iron binding capacity, whereas the bone marrow was also evaluated for the presence of iron by Pearl's reaction. Additionally, the total antioxidant capacity (TAC) and total oxidant status (TOS) were assessed, along with hepcidin and IL-6 levels. Based on the results, it was possible to observe the onset of an anemic profile, predominantly hemolytic and regenerative. Also, The other parameters showed an increase in seric iron (P < 0.01) and ferritin (P < 0.01), and a positive Pearl's reaction in T7 and T14, when compared with the control groups. Transferrin levels decreased (P < 0.05) in animals of T14 with saturation index. TAC was increased in both periods (P < 0.01), while TOS was increased only on T14 (P < 0.05). Hepcidin and IL-6 were increased on T7 and T14 (P < 0.01). Therefore, it was observed that the serum profile from infected animals showed a strong hemolytic pattern, with some demonstration of ferric tissue sequestration when the infection tended to become chronic. The results show that iron metabolism is activated in hamsters infected by L. interrogans serovar Pomona.     

Effects of Lactation and Prenatal Androgenization on the Performance,Carcass Composition,and Longissimus Muscle Sensory Characteristics of Heifers in the Single-Calf Heifer System

Two experiments were conducted to evaluate feedlot performance, lactational characteristics, and carcass composition and quality of heifers and the performance of their calves in a single-calf heifer (SCH) system. In Exp. 1, 13 [10 lactating (L) and 3 nonlactating (NL)] prenatally androgenized (PA) heifers, born to cows implanted with testosterone propionate (TP) and 19 (13 L and 6 NL) control (C) heifers, born to nonimplanted cows, were used. Heifers were calved and the pairs were placed in feedlot pens to evaluate the effects of PA on feedlot performance and lactation. Heifers were fed an 85% concentrate diet and fed to a compositional endpoint of 1.1 cm of subcutaneous fat cover, at which point calves were weaned and heifers slaughtered approximately 12 h later. The NL heifers consumed 17.0% less (P<0.01) dry matter and were 30.8% more (P<0.01) efficient in feed conversion. When calf performance was included, overall feed efficiency of L heifers was 26.9% greater (P<0.05; 0.151 vs 0.119) than that of the NL feedlot heifers. Prenatal androgenization had no effect on heifer performance. Four percent fat-corrected milk yield averaged 7.79 and 5.62 kg/d for PA and C heifers, respectively. The NL heifers had 11.0% greater (P<0.01) marbling score and yield grades were 3.77 and 3.03 (P<0.05) for NL and L heifers, respectively. Livers (P<0.01) and kidneys (P<0.05) as a percentage of shrunk weight were heavier for L heifers than for NL heifers. Two carcasses were classified as hard-boned (C-maturity) and 74% received a USDA Choice grade. The L heifers tended (P<0.10) to have lower taste panel tenderness scores; however, shearforce was similar (P=0.81) for L and NL heifers. In Exp. 2, 24 Angus × Holstein heifers were utilized in the single-calf heifer system, similar to Exp. 1. Calves were weaned from their dam between d 64 and 89 postpartum. Heifers that had their calves early weaned (EW) gained 44.2% faster (P<0.01) and consumed 10.8% less (P<0.05) DM than L heifers. The EW heifers were 60.0% more (P<0.01) efficient than L heifers. However, when calf performance was included with heifer performance, L heifers were 23.7% more (P<0.05) efficient than EW heifers. The EW heifers had 18.9% heavier (P<0.01) hot carcasses than L heifers. Backfat thickness was 1.07 and 0.66 cm (P<0.01) for the EW and L heifers.     

Administration of anesthetic and analgesic prevent the suppression of many leukocyte responses following surgical castration and physical dehorning

The objectives of the current research were to determine the physiological effects and responses of many leukocytes following surgical castration and/(or) physical dehorning and the influence of anesthetics and analgesics in 3-month-old calves. Eighty 3-month-old Holstein bull calves were completely randomized to treatments in a 2 × 2 × 2 factorial arrangement with castration, dehorning, and anesthetic/analgesic as the main effects. Peripheral blood samples were collected just before (0) and 0.5, 1.5, 2.5, 4, 6, 24, and 72 h after the respective procedure(s) and analyzed for total leukocyte and differential counts, as well as plasma cortisol and haptoglobin concentrations. Blood from the 0, 0.5 and 24 h collections were analyzed for many ex vivo leukocyte responses. Data were analyzed using a repeated measures analysis of variance with the fixed effects of treatment, time, and the interaction of treatment × time. Pre-planned contrasts were performed to determine the effect of (1) management procedure (castration and/(or) dehorning), (2) anesthetic/analgesic, and (3) were the management procedures additive. There were treatment × time interactions (P < 0.05) on plasma cortisol and haptoglobin concentrations as well as for total leukocyte and neutrophil concentrations in blood. Castration and dehorning increased cortisol concentrations and the effect of the procedures was additive (P < 0.02). Dehorning alone elicited a greater (P < 0.05) cortisol response than castration alone. In contrast, the leukocytosis and neutrophilia was greater (P < 0.01) among castrated calves. In addition, haptoglobin concentrations at 24 h after castration were elevated (P < 0.01) in calves that were castrated. Both castration and dehorning suppressed (P = 0.04) many leukocyte responses including the secretion of tumor necrosis factor-α when whole blood cultures were stimulated with lipopolysaccharide, surface expression of l-selectin on peripheral blood neutrophils, and the oxidative burst intensity of peripheral blood neutrophils when co-cultured with an Escherichia coli. The effects of castration and dehorning on blood leukocyte counts or any of the leukocyte responses were not additive (P > 0.23). Castration and dehorning effects of plasma haptoglobin concentrations tended (P = 0.10) to be additive at 72 h after the procedure(s). Prior administration of local anesthetic and a systemic analgesic attenuated (P < 0.001) the cortisol response and prevented (P = 0.03) the observed leukocytosis, neutrophilia, and leukocyte suppression. These data suggest that calves should be castrated and dehorned on the same day rather than spreading them out across two days and calves should be administered pain relief prior to performing either procedure.     

Relationship between oxidative stress and clinical–pathological aspects in dogs experimentally infected with Rangelia vitalii

The aim of this study was to evaluate lipid peroxidation, protein oxidation and activity of enzymes that are indicators of oxidative stress in Rangelia vitalii infection in dogs. Animals were divided into two groups: negative control (n = 5) and infected with R. vitalii (n = 7). After inoculation, the parasitemia was estimated daily by microscopic examination of smears. Lipid peroxidation (TBARS) and advanced oxidation protein products (AOPP); and delta-aminolevulinate dehydratase (δ-ALA-D), superoxide dismutase (SOD) and catalase (CAT) activities in blood were evaluated. The samples were collected at days 10 and 20 post-inoculation (PI). TBARS and AOPP levels were higher in the infected group in both analyzed periods (P < 0.01). The δ-ALA-D activity was reduced in blood of dogs infected with R. vitalii on days 10 and 20 PI. SOD activity was significantly increased (P < 0.01) in the blood of dogs infected with R. vitalii at days 10 and 20 PI, while CAT activity was significantly increased (P < 0.01) only at day 20 PI when compared to non-infected animals. A positive correlation was observed between the degree of parasitemia and TBARS and AOPP levels and activity of antioxidant enzymes. The δ-ALA-D activity was negatively correlated with the degree of parasitemia. Based on the increased levels of TBARS, AOPP, SOD and CAT activities, and inhibition δ-ALA-D activity, we concluded that dogs experimentally infected with R. vitalii develop a state of redox unbalance and that these changes might be involved in the pathophysiology of disease.     

The influence of spasmolytic agents on heart rate variability and gastrointestinal motility in normal horses

The effects of hyoscine-N-butylbromide (hyoscine) and propantheline-bromide (propantheline) on heart rate (HR), HR variability (HRV) and gastrointestinal tract (GIT) contractions in the normal horse were determined. Five adult horses had ECG recordings for 180 min after treatment with propantheline (100 mg), hyoscine (120 mg) or saline. Both propantheline and hyoscine reduced GIT sounds, with propantheline having a longer duration of effect (⩾120 min). Both drugs elevated HR relative to the control baseline period (P < 0.05), with the effects of propantheline again being of longer duration. HRV analysis indicated that propantheline suppressed Total Power (P < 0.05), and both the high frequency (HF) and low frequency (LF) components of the power spectral analysis for up to 60–90 min post treatment. Hyoscine had no effect on HRV Total Power but reduced the HF component for 30 min after drug injection. Time domain variables correlated with Total Power and HF data (P < 0.01). The marked effect of these compounds on parasympathetic control of cardiac and GIT function in normal horses should be taken into consideration when evaluating a clinical response to these agents.     

Kenaf Dry Matter Production,Chemical Composition,and In Situ Disappearance When Harvested at Different Intervals

Kenaf (Hibiscus cannabinus L.) is a tropical plant that has potential as a forage crop. However, data on the amount and quality of forage produced by kenaf is scarce. The objectives of this research were to determine 1) the DM yield, proportions of leaf and stalk, and chemical composition and 2) the in situ OM and N disappearance of kenaf harvested throughout the growing season. Kenaf (‘Everglades 41’) was planted in June of 1990, 1991, and 1993. The seeding rate was 5.6 kg/ha and 100 kg of N /ha was applied shortly before or after planting. Harvesting began 40 d after planting (DAP) with additional harvests at 10-d (1991 and 1993) or 20-d (1990) intervals. Daily whole plant DM accumulation ranged from 12.6 to 17.2 g/m². At 101 DAP, 726 to 974 g of DM were harvested/m². As kenaf matured, the proportion of the total plant DM represented in leaves decreased (P<0.01) from 68% at 40 DAP to 44% at 101 DAP. Leaf DM contained more (P<0.01) than twice the CP as stalk DM at all harvests. Delaying harvest decreased (P<0.01) whole plant CP concentration from 22% at 40 DP to 15% at 101 DAP, because the stalks made up a larger proportion of the total biomass. The OM in the leaves was twice as digestible (P<0.01) as the OM in the stalks (89.3 vs 44.8%). The N in the leaves was more (P<0.01) digestible than the N in the stalks (93.2 vs 61.5%). Kenaf can be grown during the summer season and harvested as high quality forage as early as 40 DAP. Whole plants harvested at 80 DAP produced from 426 to 729 g/m² of DM and had a CP content of 14 to 19%. Harvesting later than 80 DAP will increase DM yield, but CP content and in situ OM and N disappearance will decrease.     

The impact of dystocia on dairy calf health,welfare, performance and survival

Up to one-third of dairy calves are born after dystocia and this is a major cause of calf mortality. This study investigated the neonatal physiology, survival, health and subsequent growth of dairy calves following dystocia and is the first longitudinal study to analyse multiple effects and to look beyond the perinatal period.A total of 455 live born Holstein calves (N: No assistance, n = 360; FN: Farmer assistance but normally presented calf, n = 82; FM: Farmer assistance of malpresented calf, n = 13) were followed from birth to first service (heifers) or until leaving the farm (bulls). Compared to N calves, FN and FM animals had higher salivary cortisol concentrations at day 1 (P < 0.001) and FN calves had lower passive immune transfer (P = 0.03). Dystocia had no biologically significant impact on rectal temperature throughout the first 4 days (P > 0.05). During the first 60 days, FM calves had a higher proportion of days with non-routine health treatments (P < 0.05) and, by the time of weaning, mortality in FN and FM heifers was higher than in N calves (2.8×; P < 0.01). However, in surviving calves, growth to first service was not affected by dystocia category (P > 0.05).Calves which survive dystocia experience lower passive immunity transfer, higher mortality and higher indicators of physiological stress. Such calves have poorer welfare in the neonatal period and possibly beyond. Strategies need to be implemented to improve the subsequent health and welfare of such calves and to lower the incidence of dystocia.     

Grade is an independent prognostic factor for feline mammary carcinomas: A clinicopathological and survival analysis

Feline mammary carcinomas (FMC) are highly infiltrative tumours which show a strong tendency for local recurrence and metastasis. Histological type assessment of these tumours is not sufficiently discriminatory in predicting prognosis and in this study the prognostic significance of the Elston and Ellis method of histological grading was evaluated. Ninety-two feline mammary carcinomas from 84 cats were graded and 64 queens were included in a follow-up study.Grade was significantly related to tumour size (P = 0.006), clinical stage (P = 0.005), lymphovascular invasion (P < 0.0001), mitotic index (P < 0.0001), Ki67 index (P = 0.001), overall survival (P = 0.0001) and disease-free survival (P < 0.0001). Cox regression analysis identified grade as an independent prognostic factor. Multivariable analysis also showed regional lymph node metastasis and lymphovascular emboli as independent prognostic factors related to overall survival and to disease-free-survival, respectively. The study demonstrated that histological grading can be used as a prognostic factor to evaluate the biological behaviour of FMC.     

A simple novel measure of passive transfer of maternal immunoglobulin is predictive of preweaning mortality in piglets

Two factors that contribute to preweaning mortality in piglets are the initiation of lactation by sows and their ability to nurse their piglets. The objective of this study was to determine if the quantification of the transfer of immunoglobulins (Igs) from sow to piglet could act as a measure of these sow factors in terms of their influence on preweaning mortality. To measure passive transfer, a simple, rapid Ig immunocrit method was developed. For validation, the smallest piglets from 204 gilts were sacrificed on day 1 after birth and blood was collected.Piglet serum Ig concentrations were measured three ways: (1) by protein A sepharose precipitation, SDS–PAGE, and densitometry of the IgG heavy chain; (2) by precipitation of Ig with (NH₄)₂SO₄ followed by spectrophotometric measurement; and (3) by precipitation of Ig with (NH₄)₂SO₄ and measurement of the ratio of precipitate to sample volume using a hematocrit microcapillary (the Ig immunocrit method). Results from the (NH₄)₂SO₄ methods correlated (r = 0.86) with those obtained using SDS–PAGE. Day 1 weights and immunocrit ratios and preweaning survival data were then collected from every piglet from first (n = 90), and second (n = 145) parity sows. Bodyweight and immunocrit ratios accounted for 4.8% and 16.7% (P < 0.01) of the variation in preweaning mortality, respectively. Litter average immunocrit ratios were not correlated with preweaning mortality. In conclusion, the Ig immunocrit method is a simple, rapid measure of passive transfer from sow to piglet, and is useful in assessing the initiation of colostrum and the nursing ability of sows, and the effect of these events on preweaning piglet mortality.     

Selection for breed-specific long-bodied phenotypes is associated with increased expression of canine hip dysplasia

Hip dysplasia (HD) is the most common skeletal disease in purebred dogs. Radiographic schemes developed to reduce prevalence through selective breeding have had limited success, but the role of selecting for morphological characteristics prized in the show-ring and dictated by breed standards has not been fully explored. This study correlated published scores of hip pathology with measurements of body length to height ratio from photographs of Best-of-Breed specimens from 30 breeds (n = 12/breed) to establish whether selection criteria could be compromising welfare by increasing susceptibility to HD.Relative body length correlated strongly with higher rates of HD by breed data from the Orthopedic Foundation for Animals (Spearman r = 0.727, P < 0.001), the British Veterinary Association (r = 0.701, P < 0.001), and the Australian Veterinary Association (r = 0.577, P < 0.01). By favouring body shapes that are longer than they are tall, judges may be inadvertently selecting for conformational attributes predisposing dogs to HD, suggesting that ambiguity in breed standards and extreme relative body length phenotypes can engender serious welfare consequences and need to be re-evaluated.     

Evaluation of Precision Xceed® meter for on-site monitoring of blood β-hydroxybutyric acid and glucose concentrations in dairy sheep

The accuracy of the Precision Xceed® hand-held meter as an on-site method for measuring blood β-hydroxybutyric acid (BHBA) and glucose concentrations, for the diagnosis of pregnancy toxemia and ketosis in dry and lactating dairy sheep, was assessed. Five to eight hours after the start of the morning feed, blood was collected once from 193 clinically healthy sheep (143 dry and 50 lactating). BHBA and glucose analyses were performed with serum in the laboratory, and with whole blood with the Precision Xceed®. Overall, BHBA and glucose determinations by the two methods were not statistically different (P > 0.05). Strongly significant positive correlations were found for glucose and BHBA concentrations between the Precision Xceed® and laboratory results (r = 0.76, n = 150, P < 0.01 and r = 0.99, n = 193, P < 0.01, respectively). The Precision Xceed® was highly sensitive (98.6%) and specific (98.2%), and had excellent test agreement for the detection of pregnancy toxemia and ketosis.     

Effects of early weaning and breed on calf performance and carcass and meat quality in autumn-born bull calves

This study assessed the effects of age at weaning (early weaning at 90 d or traditional weaning at 150 d) and breed (Parda de Montaña or Pirenaica) on calf performance and carcass and meat quality in autumn-calving beef cattle. At calving, 14 Parda de Montaña and 14 Pirenaica cow–calf pairs were randomly assigned to one of two weaning treatments, and kept indoors during lactation. After weaning, calves were fed an intensive diet until slaughter at 450 kg. The interaction between age at weaning and breed was not significant for any of the parameters studied. From 90 d to 150 d, early weaned calves had greater ADG (P = 0.001) and IGF-I concentrations (P = 0.001) than traditionally weaned calves, but their leptin concentrations were similar (P = 0.15). During the finishing phase, performance, daily feed intake, and efficiency did not differ between treatments. Early weaning did not affect age at slaughter, carcass weight, fatness score, fat colour, and meat quality, but improved carcass conformation (P = 0.04). Early weaned calves had greater total DMI (P = 0.002) with greater concomitant feed costs (P = 0.001) and yielded a slightly greater income than traditionally weaned calves; therefore, economic margins did not differ. Parda de Montaña calves tended to have greater ADG from birth to 90 d and were heavier at 90 d (P = 0.01) than were Pirenaica calves. From 90 d to 150 d, performance and IGF-I and leptin concentrations did not differ between breeds; thus, Parda de Montaña calves remained heavier at 150 d. During the finishing phase, at times, weight gains of Parda de Montaña and Pirenaica calves differed, but the overall performance, feed intake, and efficiency of the two breeds were similar. Pirenaica calves had heavier carcasses (P = 0.04) with greater conformation scores (P = 0.04) than Parda de Montaña calves; thus, income per carcass was greater for the former than the latter (P = 0.007). As feed costs were similar for both breeds, the economic margin of Pirenaica calves was greater than that of Parda de Montaña calves (P = 0.01). In conclusion, in both breeds weaning strategies had similar effects on performance and carcass and meat quality; however, from an economic point of view, and considering only the costs associated with the calf, raising Pirenaica calves would be more profitable, at either age at weaning.     

Effect of Sustained-Release Ivermectin on Performance of Grazing Cattle in the Intermountain West

Five studies (trials I to V) were conducted on ranches located in the intermountain west to determine the effect of sustained-release parasite control (Ivomec SR Bolus®, Merial Limited, Rahway, NJ) on cattle performance and fecal nematode egg counts. Cattle in trials I to IV grazed irrigated meadows for 156 d (n=250 yearling heifers), 117 d (n=250 yearling steers), 85 d (n=150 yearling heifers), and 85 d (n=60 calves), respectively. In trial V, yearling steers (n=200) grazed dry high-desert range for 190 d. Weights and fecal samples were taken initially and at the end of each trial. Cattle were paired by weight and randomly assigned to treatment 1) Control: no deworming for the grazing period or 2) SRI: sustained-release ivermectin. For trials I to V, total gain difference (SRI minus Control) and ADG difference were 10.0 kg and 0.064 kg/d (P<0.001), 13.9 kg and 0.119 kg/d (P<0.001), 6.9 kg and 0.082 kg/d (P<0.01), 8.0 kg and 0.095 kg/d (P=0.05), and −0.48 kg and −0.003 kg/d (P=0.86), respectively. For trials I to V, mean initial, final Control, and final SRI fecal egg counts in eggs per gram were 0.4, 15.2, and 0.1; 6.0, 8.3, and 0.0; 75.8, 57.0, and 16.6; 76.0, 39.1, and 0.0; and 1.8, 2.0, and 0.0; respectively. Treatment of cattle grazing irrigated meadows with sustained-release ivermectin resulted in improved weight gain and fecal egg counts that were diminished to near zero. No differences (P>0.05) in weight gains were detected for cattle administered sustained-release ivermectin that grazed dry high desert range.     

Stocking Rate and Fuels Reduction Effects on Beef Cattle Diet Composition and Quality

An experiment was conducted to evaluate the influence of forest fuels reduction on diet quality, botanical composition, relative preference, and foraging efficiency of beef cattle grazing at different stocking rates. A split plot factorial design was used, with whole plots (3 ha) being fuel reduced or no treatment (control), and split plots (1 ha) within whole plots were grazed to three levels of forage utilization; (low) 3 heifers · ha^?1, (moderate) 6 heifers · ha^?1, (high) 9 heifers · ha^?1, with a 48-h grazing duration. Grazing treatments were applied in August of 2005 and 2006. Cattle diet composition and masticate samples were collected during 20-min grazing bouts using six ruminally cannulated cows in each experimental unit. Relative preference indices indicated a strong preference for grass regardless of treatment and stocking rate. Grass consumption was lower in control pastures (P < 0.05) and tended (P < 0.095) to decrease with increased stocking rates. Shrub use was higher in control pastures displaying a quadratic effect (P < 0.05) due to stocking, whereas shrub use increased with stocking rate across all treatments. Cattle grazing control pastures consumed diets higher in crude protein compared to cattle grazing treated pastures (P < 0.05). In vitro dry matter digestibility values were lower (P < 0.05) in control sites and tended (P = 0.10) to decrease with increased stocking rates. In both control and treated pastures, bites per minute and grams consumed per minute declined (P = 0.003) with increased stocking, indicating foraging efficiency of cattle decreases with increased stocking rates. Our data indicated cattle grazing late season grand fir habitat types have a strong preference for grasses regardless of treatment or stocking rate. However, as stocking rate increased in both control and treated pastures, grass consumption decreased, shrub consumption increased, and foraging efficiency decreased.