Sperm distribution in the reproductive tract of sows after intrauterine insemination

The purpose of the present study was to compare the number of spermatozoa obtained from different parts of the oviducts and the uterine horns of sows after intrauterine insemination (IUI) and conventional artificial insemination (AI), 24 h after insemination. Twelve crossbred (Landrace x Yorkshire) multiparous sows were used in the experiment. The sows were examined for standing oestrus using a back pressure test and were examined every 4 h after standing oestrus by real-time B-mode ultrasonography to estimate the time of ovulation. The sows were allocated to two groups, group I sows (n = 6) were inseminated by a conventional AI technique with 3 x 10(9) motile spermatozoa in 100 ml of extended semen, and group II sows (n = 6) were inseminated by an IUI technique using 1 x 10(9) motile spermatozoa in 50 ml of extended semen. A single dose of AI or IUI was given using the same boar, 8-10 h before the expected time of ovulation during the second oestrus after weaning. Twenty four hours after insemination, the sows were ovario-hysterectomized. The oviducts and the uterine horns were removed and divided into seven parts, the cranial, middle and caudal uterine horns, the utero-tubal junction (UTJ), the cranial and caudal isthmus, and the ampulla. All parts of the reproductive tract were flushed and the spermatozoa were counted using a haemocytometer. The results revealed that the spermatozoa were found in both the oviducts and the uterine horns in all animals. The number of flushed spermatozoa in the UTJ of groups I and II, was 142,500 and 131,167 (p > 0.05), and in the caudal isthmus was 1411 and 1280 (p > 0.05), respectively. The proportion of spermatozoa in different parts of the reproductive tract in relation to the total number of spermatozoa within the tract was not significantly different between groups I and II (p > 0.05). It could be concluded that IUI, with a three-time reduction in the number of spermatozoa used resulted in the same number of spermatozoa to be deposited in the sperm reservoir around ovulation time.     

Warm weather transport of broiler chickens in Manitoba. II. Truck management factors associated with death loss in transit to slaughter

This observational study was conducted to identify the cause of death and load level factors associated with mortality in 1 090 733 Manitoba broiler chickens transported to slaughter in spring and early summer. Death loss in transit was 0.346% and accounted for 19% of the total carcass condemnation. The death loss pattern was clearly bimodal, with a low death loss in 180 of 198 shipments. Cumulative death loss during the growing phase of production was consistently associated with increased transport mortalities in load level models and when comparing high death loss with low death loss truckloads. High ambient temperature at the time of slaughter and loading density of the truck were the major factors associated with exceptional death loss.     

Evaluation of an antigen capture ELISA for the early diagnosis of Hypoderma lineatum in cattle under field conditions

An antigen capture or sandwich ELISA (sELISA) was evaluated for the diagnosis of Hypoderma lineatum in cattle under field conditions in northwestern Spain. The kinetics of circulating hypodermin C (HyC) and specific antibodies during the course of natural infestation were determined in a group of 10 Frisian calves. In addition, oesophagi and blood samples were taken from 105 cows at a slaughterhouse in order to compare three methods for the diagnosis of H. lineatum: sandwich ELISA for the detection of the antigen HyC (sELISA), indirect ELISA for the detection of antibodies anti-HyC (iELISA) and the detection of first instars (L1) in the oesophagus. In naturally infested cattle, HyC was present in circulation at low levels during the early and late phases of the infestation. However, in the middle phase, coinciding with the presence of L1 in the oesophagus, two peaks of increased HyC concentration were observed. Specific antibodies increased progressively until the first appearance of larvae in warbles on the back. There was no correlation between antigen or antibody levels and the number of grubs in the back. Prevalence of first instars in the oesophagi of slaughtered cows was 21.9% (23/105). The percentage of cattle that were positive for circulating antigen was slightly higher (24.8%), suggesting the recent destruction of migrating larvae in some animals. However, there was no correlation between the number of L1 and HyC levels. With the iELISA, 79% of the animals were positive to Hypoderma, which means that a high percentage of those animals have been exposed to the parasite but they had no apparent current infestation. The sELISA is a good tool to follow larval development within the host; however, the episodic elevation of HyC levels limits the usefulness of this test for the early diagnosis of Hypoderma under field conditions.     

B-cell lymphoma in a dog with ehrlichiosis (Ehrlichia canis) and systemic histoplasmosis (Histoplasma capsulatum)

A mixed breed dog treated for ehrlichiosis and systemic histoplasmosis developed a refractory thrombocytopenia. When an abdominal mass was detected, exploratory laparotomy and biopsies confirmed lymphoma, which on immunohistochemical stains was determined to be of B-cell origin. Conceivably, the B-cell lymphoma in this dog was associated with chronic inflammation from ehrlichiosis, histoplasmosis, or both.     

Evaluation of the effectiveness of two infectious bronchitis virus vaccine programs for preventing disease caused by a California IBV field isolate

Infectious bronchitis virus CA99 serotype was isolated from several broiler flocks in Northern California. The virus caused late-onset respiratory disease and increased airsacculitis condemnation in affected flocks despite the use of an established infectious bronchitis virus vaccination program. An experimental study compared Holland/Arkansas and Massachusetts/Arkansas vaccination protocols to determine the efficacy of commercial infectious bronchitis virus vaccines in reducing respiratory disease and airsacculitis lesions found at processing that were associated with a CA99 field isolate. All vaccination groups were given Massachusetts/Connecticut strains of infectious bronchitis virus vaccines at age 1 day followed by vaccination with either Holland/ Arkansas or Massachusetts/Arkansas vaccine strains at 18 days of age. Birds were challenged at age 31 days with a CA99 field isolate. Gross pathology, histopathology, and virus isolation were evaluated. Chickens vaccinated with Holland/Arkansas had marginally better protection against CA99 challenge than chickens vaccinated with Massachusetts/Arkansas, although differences were not statistically significant.     

Effect of carazolol on the oestrous behaviour and concentrations of luteinising hormone and steroids in lactating cows during the periovulatory period

Twelve multiparous, cycling, lactating Holstein-Friesian cows were synchronised with prostaglandin F(2alpha) and treated with either 2.5 mg carazolol or saline. There were no differences between the peripheral blood concentrations of oestradiol or progesterone, but in the cows treated with carazolol the periovulatory surge of luteinising hormone was delayed, and oestrous behaviour was expressed later than in the control cows.     

A ten-year review of commercial vaccine performance for control of tick infestations on cattle

Ticks are important ectoparasites of domestic and wild animals, and tick infestations economically impact cattle production worldwide. Control of cattle tick infestations has been primarily by application of acaricides which has resulted in selection of resistant ticks and environmental pollution. Herein we discuss data from tick vaccine application in Australia, Cuba, Mexico and other Latin American countries. Commercial tick vaccines for cattle based on the Boophilus microplus Bm86 gut antigen have proven to be a feasible tick control method that offers a cost-effective, environmentally friendly alternative to the use of acaricides. Commercial tick vaccines reduced tick infestations on cattle and the intensity of acaricide usage, as well as increasing animal production and reducing transmission of some tick-borne pathogens. Although commercialization of tick vaccines has been difficult owing to previous constraints of antigen discovery, the expense of testing vaccines in cattle, and company restructuring, the success of these vaccines over the past decade has clearly demonstrated their potential as an improved method of tick control for cattle. Development of improved vaccines in the future will be greatly enhanced by new and efficient molecular technologies for antigen discovery and the urgent need for a tick control method to reduce or replace the use of acaricides, especially in regions where extensive tick resistance has occurred.     

Treatment of severe immune-mediated thrombocytopenia with human IV immunoglobulin in 5 dogs

BACKGROUND: Glucocorticoids with or without other immunotherapy are the initial treatment of choice for dogs with severe immune-mediated thrombocytopenia (IMT). The majority of treated dogs will have improvements in platelet counts within 5 to 7 days of starting therapy, but complications from hemorrhage often occur before a response is seen. Human IV immunoglobulin (hIVIG) blocks Fc receptors on mononuclear phagocytic cells in dogs; it is used in people with idiopathic thrombocytopenic purpura. HYPOTHESIS: The purpose of this study was to describe adverse effects and benefit of hIVIG in addition to conventional immunosuppressive therapy in dogs with severe IMT. ANIMALS: Five client-owned dogs with severe primary IMT. METHODS: Case series. The hospital database was searched for dogs with primary IMT treated with hIVIG. RESULTS: No adverse effects were noted during or after hIVIG infusion in any treated dog. Over a 6-month follow-up, all dogs were clinically normal when using conventional immunosuppressive therapy. Human IVIG was administered 3 days after initiation of immunosuppressive therapy in 4 dogs, and, after 2 days, in 1 dog. In all dogs, the mean platelet counts pre- and 24 hours post-hIVIG infusion (0.28-0.76 g/kg) were 2,500/pL and 50,600/microL (62,750/microL for the 4 responders), respectively. One dog failed to respond as promptly to hIVIG (0.34 g/kg), and the platelet count increased to 66,000/microL after 9 days of immunosuppressive therapy. The mean duration of hospitalization post-hIVIG in all 5 dogs was 1.8 days (12 hours for responders), and the mean total length of hospitalization was 4.6 days (3.5 days for responders). Active hemorrhage resolved and no packed red blood cell transfusions were required after hIVIG infusion for responders. CONCLUSIONS AND CLINICAL IMPORTANCE: Human IVIG was well tolerated and appeared to be associated with rapid platelet count recovery and amelioration of clinical signs in most dogs with IMT.