The role of histamine and fish meal in the incidence of gizzard erosion and pro‐ventricular abnormalities in the fowl

1. The role of certain fish meals in the production of localised gizzard erosion is confirmed.

2. Lesions typical of gizzard erosion could be produced by the addition of histamine to the diet.

3. The amount of histamine occurring naturally in fish meal depends on the species of fish and the extent and nature of bacterial spoilage.

4. These variables may explain why histamine has not been implicated previously and also why there have not been consistent associations between the condition and geographical source or common factors in bulk consignments of the meal.     

Light at the end of the tunnel? Advances in the understanding and treatment of glaucoma and inherited retinal degeneration

Glaucoma and inherited retinal degeneration/dystrophy are leading causes of blindness in veterinary patients. Currently, there is no treatment for the loss of vision that characterizes both groups of diseases. However, this reality may soon change as recent advances in understanding of the disease processes allow researchers to develop new therapies aimed at preventing blindness and restoring vision to blind patients. Elucidating the molecular mechanisms of retinal ganglion cell death in glaucoma patients has led to the development of neuroprotective drugs which protect retinal cells and their function from the disastrous effects of elevated pressure. Identification of the genetic mutation responsible for inherited degenerations and dystrophies of the outer retina has enabled researchers using gene therapy to restore vision to blind dogs. Other patients may benefit from retinal transplantation, stem cell therapy, neuroprotective drugs, nutritional supplementation and even retinal prostheses. It is possible that soon it will be possible to restore sight to some blind patients.     

Evaluation of Dairy–Yeast Prebiotic Supplementation in the Diet of Juvenile Goldfish in the Presence or Absence of Phytoplankton and Zooplankton

Abstract

Prebiotics recently have been shown to increase immune responses and disease resistance in certain fish species; therefore, the current study was conducted to evaluate the commercially available dairy–yeast prebiotic, GroBiotic-A, for use with juvenile goldfish Carassius auratus. The study consisted of two 10-week feeding trials in which juvenile goldfish were fed practical diets that were either unsupplemented or supplemented with the dairy–yeast prebiotic at 2% by dry weight. Juvenile fish were sorted by size and stocked into 12 units within each of two culture systems: one indoor system supplied with recirculated well water and one system located outdoors with a continuous flow of pond water to provide a source of phytoplankton and zooplankton. Both diets were fed to fish in six units within each system at the same fixed percentage of body weight twice daily. Culture system (i.e., presence or absence of phytoplankton and zooplankton) was the primary factor influencing (P < 0.0001) percent weight gain, feed efficiency, and survival of goldfish during the feeding trials. No dietary effect was detected, although there was a significant (P < 0.05) interaction between culture system and diet, with supplementation of the dairy–yeast prebiotic tending to improve weight gain and feed efficiency of fish in the presence of phytoplankton/zooplankton. During a controlled disease challenge with an intraperitoneally administered dose of Aeromonas hydrophila that was equivalent to a predetermined LD50 (dose lethal to 50% of test fish), average survival values ranged between 67% and 83% for fish that previously had access to phytoplankton/zooplankton compared with 17–33% for fish that had no access to phytoplankton/zooplankton. The dairy–yeast prebiotic, however, did not enhance resistance of goldfish to the bacterial pathogen and did not greatly alter microbiota of the anterior or posterior gastrointestinal tract based on denaturing gradient gel electrophoresis analysis. In conclusion, the dairy–yeast prebiotic did not improve feed efficiency in goldfish or resistance to a bacterial pathogen as previously observed in golden shiners Notemigonus crysoleucas and hybrid bass (white bass Morone chrysops × striped bass M. saxatilis).     

Involvement of tannins and flavonoids in the in vitro effects of Newbouldia laevis and Zanthoxylum zanthoxyloïdes extracts on the exsheathment of third-stage infective larvae of gastrointestinal nematodes

The present study aimed at examining the possible role of tannins and flavonoids on the in vitro anthelmintic properties of the extracts of two plants from the southern area of Western Africa, i.e. Newbouldia laevis and Zanthoxylum zanthoxylo?des. Extracts of the two plants were prepared by use of acetone/water (70/30) and their anthelmintic activity was measured by use of the larval exsheathment inhibition assay (LEIA) applied on the abomasal species, Haemonchus contortus and the intestinal species Trichostrongylus colubriformis. Three concentrations of extracts were evaluated to examine the possible dose effect. In addition, the possible involvement of tannins and flavonoids was examined by comparing the levels of inhibition of larval exsheathment obtained with the same extracts, after of not addition of PVPP which forms complexes with these compounds. The results indicate significant effects with both plants and both nematode species. In the range of concentrations examined, the results were dose-dependent for N. laevis extracts but not for Z. zanthoxylo?des because the three doses applied provoked a similar highly significant inhibition whatever the tested dose. The use of PVPP indicated for both plant and nematode species, that tannins and flavonoids are involved partly in the effect but that some other biochemical compounds were also involved in both plants.     

Expression and Localization of Integrin αv in Different Parts of the Fallopian Tube in Reproduction Cycle of Yak

The objective of this study was to explore the expression differences of integrin αv in different parts of the fallopian tube at different reproduction stages of yak, and provide some important theoretical foundations for understanding the effect of integrin αv on the reproductive performance of yak. The samples of the tubal umbrella, ampulla, and isthmus of healthy female yaks (3-6 years old) during follicular, luteal and pregnancy stages were collected, the fallopian tubes of the follicular phase, the luteal phase and the pregnancy phase were divided into 9 groups according to the umbrella, ampulla and isthmus. Real-time PCR (qRT-PCR) and Western-blotting (WB) were used to detect the expression of integrin αv gene and protein. The expression of integrin αv protein was localized by immunohistochemistry. Results: 1) qRT-PCR results showed that, during the follicular phase, the expression of the integrin αv gene in the umbrella of the fallopian tube was the highest and extremely significantly higher than those in the ampulla and isthmus (P<0.01). During the luteal phase, the expression of the integrin αv gene in the isthmus of the fallopian tube was the highest and extremely significantly higher than those in the umbrella and ampulla (P<0.01). During the pregnancy phase, the expression of the integrin αv gene in the umbrella of the fallopian tube was the highest and extremely significantly higher than those in the ampulla and isthmus (P<0.01). 2) Western-blotting results showed that, during the follicular phase, the expression of integrin αv protein in the umbrella of the fallopian tube was the highest and extremely significantly higher than those in the ampulla and isthmus (P<0.01). During the luteal phase, the expression of integrin αv protein in the isthmus of the fallopian tube was the highest and extremely significantly higher than those in the umbrella and ampulla (P<0.01). During the pregnancy phase, the expression of integrin αv protein in tubal isthmus and umbrella was not significantly different, but these were extremely significantly higher than that in the ampulla (P<0.01). 3) The results of immunohistochemistry showed that integrin αv protein was positively expressed in ciliated cells, secretory cells, basal cells, muscular layers and serous glands of the fallopian tube umbrella, ampulla and isthmus. The results indicated that the expression of integrin αv in different parts of the fallopian tube at different reproduction stages of the yak were significantly different, which showed that αv might be involved in a series of reproductive processes such as fertilization and early embryonic development, the results provided basic information for the study of yak's reproductive performance.     

Effect of Freezing Rates and Supplementation of α-Tocopherol in the Freezing Extender in Equine Sperm Cryosurvival

This study was conducted to determine the impact of antioxidant (α-tocopherol) supplementation in the cryopreservation extender and three different freezing rates (FRs) on quality of post-thaw semen to elaborate a new protocol for stallion semen cryopreservation. Six ejaculates from each of four stallions were subjected to cryopreservation with a commercial extender (Gent, Minitub Iberia, Spain), without any supplementation (control) or supplemented with 2 mM α-tocopherol. The semen was exposed to three different freezing rates between 5°C and −15°C: slow (5°C/min), moderate (10°C/min), and fast (20°C/min). After thawing, the sperm viability (Sybr-14 and propidium iodide [PI]), mitochondrial membrane potential (MMP) (5,5′,6,6′-tetrachloro-1,1′,3,3′tetraethylbenzimidazolyl carbocyanine iodine), lipid membrane peroxidation (LPO; C₁₁-BODIPY^581/591), and apoptosis status (fluorescein isothiocyanate–conjugated annexin V and PI) of the plasmatic membrane of each sample were determined by flow cytometry. For both extenders, the percentage of viable cells was higher for spermatozoa cooled at 5°C/min than at 10°C/min and 20°C/min (P ≤ .05). The FR of 20°C/min demonstrated a lower value of MMP than the FR of 5°C/min and 10°C/min (P ≤ .05). The α-tocopherol extender improved (P ≤ .05) post-thaw membrane LPO; however, it did not improved viability and the apoptosis status of the sperm plasmatic membrane after thawing. In conclusion, results clearly indicate that the cryosurvival of stallion spermatozoa is improved when FR of 5°C/min is used from 5°C to −15°C.     

Variation among individual white‐leghorn hens in the concentration of minerals in the albumen and yolk content of their eggs

1. The mineral composition of the albumen and yolk was determined in several eggs from each of a number of individual hens from the same White‐Leghorn strain. X‐ray fluorescent spectrometry was used to undertake two independent series of analyses. A total of 8 minerals (calcium, chlorine, iron, magnesium, phosphorus, potassium, sodium, sulphur) were included in the analyses of the yolk and the same minerals, but excluding iron (which is present in only small amounts), in the albumen.

2. There was considerable variation between individuals in the mineral concentration in their eggs (coefficients of variation ranged between 3.8% for sodium to 19.9% for calcium in the albumen, and between 4.3% for phosphorus to 11.8% for iron in the yolk).

3. At the same time, the moderately high repeatability of mineral concentration (t = 0.4?0.6) in successive eggs from the the same hen for several of the minerals analysed is indicative of some positive control by the hen of the mineral composition of her eggs.

4. There was a highly significant correlation (P≤ 0.001) between the mean concentration of potassium in the albumen and the hatchability of the eggs, supporting the claim that a deficiency of potassium in the egg could be the basis of some failures in hatchability.

5. The study also revealed variation among individual birds in the concentration of iron in the yolk which was negatively correlated (P≤0.01) with hatchability. No clear basis could be suggested for this variation among individual birds.     

Changes in the acid‐base parameters of venous porcine blood caused by the period of storage and the method of sampling

Summary

The experiments demonstrate that the acid‐base status of porcine blood does not change significantly during a six hours’ storage period at 0° C. They further show that the sampling of blood via a vena cava puncture in comparison with sampling via an indwelling ear vein catheter is associated with severe stress that affects the acid‐base statuts of the blood.     

A survey of the prevalence of blowfly strike and the control measures used in the Rûens area of the Western Cape Province of South Africa

Blowfly strike and the methods used to combat blowfly strike were recorded on 33 properties in the R?ens area of South Africa during 2003/2004. Data were recorded on Merino and Dohne Merino hoggets (n = 4951) with at least 3 months' wool growth. The following data were captured: presence or absence of strike, site of the strike (body or breech), presence or absence of dermatophilosis as well as subjective scores for wool quality and wool colour. Control measures recorded include: chemical treatment (preventative and spot treatment), crutching, mulesing and the use of the Lucitrap system. Blowfly strike was not significantly influenced by gender or breed. Hoggets suffering from dermatophilosis were more likely to be struck, compared with contemporaries not suffering from the skin disorder (0.057 vs 0.027; P < 0.05). Merino hoggets generally had higher scores than their Dohne Merino contemporaries for wool quality (32.6 vs 27.4; P < 0.05) and wool colour (29.0 vs 27.2; P < 0.05). There was an indication that the Lucitrap system may have reduced flystrike, but the effect was not statistically significant (P = 0.19 for overall strikes and P = 0.12 for body strike). The Mules operation benefited overall flystrike (0.013 vs 0.110; P < 0.05); mainly through an effect on breech strike (0.010 vs 0.109; P < 0.05). The proportion of fly strikes increased with wool length, and declined with an increase in farm size in wool colour score. None of the ethically acceptable control measures assessed could substantially reduce blowfly strike on their own, and an integrated pest management programme was proposed.     

Serological and parasitological survey of dourine in the Arsi–Bale highlands of Ethiopia

This study was conducted from August 2005 to January 2007 to determine prevalence and distribution of dourine in horses and to investigate the occurrence of clinical and carrier cases in donkeys and mules in the Arsi–Bale highlands. Study methodology was based on questionnaire, serological, clinical and parasitological survey. The questionnaire indicated that dourine is a major health problem of equines in the Arsi–Bale highlands. Though dourine is commonly observed throughout the year, it has a seasonal character and occurs mostly during the breeding season from June to late September. Serological screening of 646 horses showed a seroprevalence of 184 (28%), 161 (25%) and 125 (19%) for card agglutination test for trypanosomosis, LATEX and enzyme-linked immunosorbent assay, respectively. Risk factors were parity number, previous history of abortion and body condition score. No trypanosomes could be detected by Giemsa staining or by haematocrit centrifugation technique. Ten puppies inoculated with blood samples, genital washes and oedematous fluids remained parasitologically negative. Different characteristic signs of dourine were observed. During the genital stage, mares showed vaginal oedema, discharge and presence of depigmented scars over the external genitalia. In stallions, oedema of the scrotum and prepuce, prepucial and urethral discharge, and ulceration of the genital mucosae mainly of the penile were observed. In both sexes, lameness in one or both legs, partial dragging and stiffness of the hind legs and incoordination were the dominant signs observed as nervous form of the disease.     

The role of Bcl-xL and nuclear factor-��B in the effect of taxol on the viability of dendritic cells

Taxol has been used effectively in cancer therapies. Our previous study demonstrated that taxol induced altered maturation and improved viability of dendritic cells (DCs). However, the effects of taxol on DC viability have not been fully elucidated. In the present study, flow cytometric analyses revealed that taxol treatment significantly increased the number of viable DCs and the expression levels of a representative anti-apoptotic protein Bcl-xL. Furthermore, mobilization of the p65 subunit of nuclear factor-κB (NF-κB) from the cytosol to the nucleus in DCs was observed by confocal microscopy. An inhibition assay using N-p-tosyl-_L-phenylalanine chloromethyl ketone confirmed that NF-κB was intimately involved in the effects of taxol on DC viability. In addition, we investigated the mechanisms of taxol enhancement of DC viability. Since taxol is a popular anticancer agent used in clinic, this study may provide a rationale for the use of taxol in DC immunotherapy to treat cancer patients. Taken together, these results confirm that taxol increases DC viability, and this information may provide new insights for new clinical applications of both taxol and DCs.     

Role of interleukin-1β in the regulation of porcine corpora lutea during the late luteal phase of the cycle and during pregnancy

Interleukin-1β (IL-1β) may regulate ovarian physiology. In this study, the influence of IL-1β on secretory activity within the corpora lutea (CL) of cyclic and gravid pigs was determined in vitro during different stages of the CL lifespan, e.g. on Days 10-11, 12-13 and 15-16 of the oestrous cycle and pregnancy. IL-1β (10 ng/ml) increased prostaglandin E2 (PGE2) secretion from CL of the cyclic and gravid pigs during studied days of the oestrous cycle and pregnancy. Increase (P < 0.05) of prostaglandin F2α (PGF2α) in IL-1β-treated CL was demonstrated only on Days 10-11 of the oestrous cycle. More potent stimulatory effect of IL-1β on PGE2 than PGF2α secretion resulted in the enhancement of the PGE2:PGF2α ratio in cyclic and early pregnant CL. IL-1β increased (P < 0.05) progesterone (P4) secretion only in gravid CL and had no effect on oestradiol-17β (E2) release. Expression of cyclooxygenase-2 (COX-2) mRNA was stimulated (P < 0.05) in IL-1β-treated cyclic and gravid CL. Expression of prostaglandin synthase mRNAs in response to IL-1β did not increase. In conclusion, IL-1β modulates PGE2, PGF2α and P4 secretion from porcine CL, depending on luteal stage and the surrounding hormonal milieu. The cytokine may act locally in porcine CL for luteotrophic support throughout the PGE2-mediated synthesis and secretion.     

A Comparison of the Concentrations of C-reactive Protein and α1-Acid Glycoprotein in the Serum of Young and Adult Dogs with Acute Inflammation

The concentrations of C-reactive protein (CRP) and ₁-acid glycoprotein (AAG) were evaluated in 1-, 3- and 18-month-old dogs (four of each age) that had been inoculated with turpentine oil. The CRP and AAG in 3-month-old and younger dogs subjected to surgery or inoculated with either Staphylococcus aureus or a viral vaccine were also evaluated. The average CRP concentration in the sera peaked 2 days after inoculation of turpentine oil. The peak CRP concentrations in 3- and 18-month-old dogs were significantly (p<0.05) greater than those in 1-month-old dogs. The average AAG concentration in the sera peaked 4 days after inoculation of turpentine oil. No significant difference was found in AAG concentrations between any of the age groups. When experimentally inoculated with S. aureus or subjected to oophorohysterectomy, the CRP and AAG concentrations increased in 3-month-old dogs, but they increased little in 1-month-old dogs. The CRP and AAG in dogs inoculated with the viral vaccine did not increase. In dogs with fractures or subjected to percutaneous gastrostomy, the CRP and AAG concentrations correlated with the condition of dogs.     

Characteristics of Nutrient Contents and Evaluation of Nutritional Value of the Alpine Grassland Plants in the Source Area of the Yellow River北大核心CSCD

In order to explore the characteristics of nutrient contents and scientifically evaluate the nutritional value of the alpine grassland plants in the source area of the Yellow River, the plants of the five different alpine grasslands were selected as the research objects, and the content of crude protein (CP), ether extract (EE), crude fiber (CF), crude ash (CA), total phosphorus (TP) of the plants were determined. At the same time, the principal component analysis method was used for quantitative comprehensive evaluation of the plants nutritional value. The results showed that the CP content of the plants in all alpine grasslands was between 12.78%~15.35%, the EE content was between 2.63%~3.38%, the CF content was between 17.56%~25.16%, the CA content was between 5.52%~11.53% and the TP content was between 0.11%~0.27%. The order of nutrient value of plants in different alpine grassland from high to low was: degraded alpine meadow > native alpine meadow > swamp meadow > degraded alpine steppe> native alpine steppe;The order of yield per unit area of the total nutrients of plants in different alpine grasslands from high to low was: swamp meadow > native alpine meadow > native alpine steppe> degraded alpine steppe> degraded alpine meadow;The order of nutrient value of different plant species from high to low was: Leguminosae>Forbs >Cyperaceae>Gramineae. © 2019 Authors. All rights reserved.     

An overview of themes in the agrarian and environmental history of the Karoo since c.1800§

This article explores some themes in the agrarian and environmental history of the Karoo since 1800. It argues that environmental change cannot be understood without incorporating social, economic and political history. This is especially so in the case of the Karoo because the landscape and ecology was transformed by intensive commercial livestock production in the nineteenth and twentieth centuries. The scale and economic significance of sheep farming and wool production up to the 1960s is generally underestimated in histories of the Cape and South Africa. The article outlines the patterns of economic growth and also the technologies required, such as fencing and water provision. The environmental impact of intensive livestock farming was recognised from the late eighteenth century and new scientific approaches helped to define understandings of environmental change. Environmental degradation was at its height in the first half of the twentieth century; simultaneously, conservationist ideas were developed and gradually implemented. In the second half of the twentieth century, these approaches, together with socio-economic factors that led to lower levels of stocking, resulted in a stabilisation and even some environmental recovery.     

Morphological Observation on the Test and Epididymis in Hybrid of Wild and Domestic Yaks During the Growth Periods

This paper was carried out on the morphological character of the test and epididymis of three types of yak bull age 6,12,18,24 months old (1/2 wild yak, cross 1/2 wild yak and domestic yak). The results showed that the weight and size of testes and epidiymis was increased with the age which was hardly affected by imbalance of food supply during the cold and warm seasons. The development were similar for three kinds of yak at the same age(P＞0.05).     

Dose measurement in small animal radiology: how intense is the influence of distance and position of the investigator in relation to the patient?

Radiation exposure of body parts of persons, needed to restrain small animal during the examination, varies depending on the distance and position in relation to the patient, the region investigated, and the exposure settings applied. The aim of the study was to quantify the effects of these factors on the ambient dose. The dosimeter was positioned with varying distance from the direct beam (from 30 to 150 cm) and on different level above the floor (55 cm, 85 cm, and 150 cm. The study consisted of two parts. In the first part a plastic water tank (thickness: 18 cm) was used as source of scatter radiation. Different exposure settings (77 kVp; 20 - 10 - 5 - 2.5 - 1.25 mAs) were applied. In the second part dose was measured during the examination of the abdomen of a large dog (thickness: 18 cm; 77 kVp, 20 mAs) and of the skull of a cat (thickness: 6 cm; 55 kVp, 20 mAs). At the level of the patient (85 cm above the floor) the dose decline relative to the distance followed a quadratic function. In the series "abdomen-dog" the mean dose values ranged from 51.6 microSv (30 cm distance) to 1.02 microSv (150 cm distance). The corresponding doses for the series "skull-cat" were 0.98 microSv and 0.02 microSv, respectively. Comparably lower doses were measured on the lines along the table, when non-irradiated parts of the body were located between the exposed patient volume and the dosimeter. At 150 cm above the floor higher doses were observed relative to the doses at the level of the table. The following conclusions can be drawn: (1.) Depending on the target volume the ambient dose varies in a wide range. (2.) An increase of the distance of only few centimetres is reducing exposure considerably. Therefore persons should make use of it whenever this is possible. (3.) Persons should stand on the short sides of the table while fixing the patient. (4.) Head and neck are relatively highly exposed. Methods to protect the thyroid gland and the eye lens are indicated. (5.) Since different exposure levels can be applied in digital radiography, the range of dose levels is rather wide. Therefore strict dose discipline (e.g. by use of exposure tables and dose indicators) is necessary to avoid continuing overexposure.