Egg production responses of hens given a complete mash or unground grain together with concentrate pellets

Thirty‐three light hybrids aged 11 months were caged individually and fed for S weeks according to three regimes, viz. A, a conventional mash ad libitum; B, a mixture of whole wheat, barley and kibbled maize ad libitum in the morning, with concentrate pellets ad libitum in the afternoon; or C, ad libitum the same grain mixture together with concentrate pellets and oystershell grit in the ratio 70 : 23 : 7 so that the nutritive value of the complete diet was similar to that of the conventional mash. The concentrate pellets used in the two regimes differed. Those used in regime B contained ground limestone while those used in regime C did not.

Egg production was similar on the three regimes (74.8, 74.7 and 74.5% respectively) . Food intake was lowest on regime C and highest on regime B, although the intakes of metabolisable energy were very similar on the three regimes. Compared with the results obtained with the conventional mash diet (regime A), the conversions of food and dietary protein to eggs were lower on regime B but higher on regime C.     

The effect of bovine viral diarrhea virus infections on health and performance of feedlot cattle

The aim of this study was to investigate the effect of bovine viral diarrhea virus (BVDV) infections (unapparent acute infections and persistent infections) on the overall health and performance of feedlot cattle. Calves from 25 pens (7132 calves) were enrolled in the study. Overall and infectious disease mortality rates were significantly higher (P < 0.05) in pens categorized at arrival as positive for type I BVDV and lower in pens that were positive for type II BVDV than in negative pens. Mortality attributed to BVDV infection or enteritis was significantly more common (P < 0.05) in the pens containing persistently infected (PI) calves than in pens not containing PI calves (non-PI pens). There were no statistically detectable (P > or = 0.05) differences in morbidity, overall mortality, average daily gain, or the dry matter intake to gain ratio between PI and non-PI pens. Although type-I BVDV infections in feedlots appear to contribute to higher mortality rates, the presence of PI calves alone does not appear to have a strong impact on pen-level animal health and feedlot performance.     

Spindle cell sarcoma in the kidney of a dog

A spindle cell sarcoma involving the left kidney was diagnosed in a 14-year-old male Basenji. Radiography and ultrasonography were used to define the extent and location of the mass. Metastatic disease was not detected. An 8 x 5-cm mass, involving the left kidney, was resected by performing nephroureterectomy. Signs of metastasis were not detected at 3 and 6 months after surgery. Shortly after the 6-month examination, the dog was euthanatized because of perceived signs of pain attributable to cervical disk disease. Postmortem examination was not performed. Histologic examination consisted of use of hematoxylin and eosin, Masson trichrome, and van Gieson stains, and 4 immunoperoxidase techniques. On the basis of the histologic findings, the final diagnosis was spindle cell sarcoma, with the 2 most likely possibilities being leiomyosarcoma and fibrosarcoma.     

Use of dihaploid potatoes in breeding for ground frost resistance

Ground frost resistance is important for the growing of early potatoes and of othervarieties on soils which are prone to suffer from ground frosts. Resistance has beenfound, among others, in the primitive diploid cultivated potato species S. ajanhuiri.The clones of this species which are included in the Wageningen Potato Collection(WAC) were not crossable to ordinary varieties of the species S. tuberosum. However,it was shown to be possible to cross S. ajanhuiri with a dihaploid form of S. tuberosum.Amphidiploid plants were obtained after colchicine treatment. These plants werefertile when crossed with ordinary varieties. Some of the hybrids possess a certainfrost resistance. Backcrosses will be necessary to obtain varieties with good consump-tion qualities.     

Immunization of cattle with nymphal Hyalomma anatolicum anatolicum extracts: effects on tick biology

Antigens derived from partially engorged nymphs of Hyalomma anatolicum anatolicum were used in immunizing crossbred (Bos indicus×Bos taurus) cattle against larval, nymphal and adult H. a. anatolicum and H. dromedarii. The cattle were either infected with Theileria annulata at low parasitaemia or were uninfected. Whole nymphal extract (WNE), nymphal membrane antigens (NMA) and nymphal soluble antigens (NSA) were used for immunization. The group immunized with WNE showed significant and better rejection of H. a. anatolicum ticks as compared to calves immunized with either NMA or NSA. The moulting rates of both engorged larvae and nymphs remained unaffected. Nymphs which engorged on the immunized calves were fully susceptible to infection by T. annulata as indicated by the intensity and abundance of Theileria infections in the resulting adult ticks from immunized and unimmunized Theileria infected cattle. These ticks also transmitted fatal theileriosis to susceptible calves.     

Estimation of the effect of lead and cadmium ions on fluctuating asymmetry in leaves of the common bean (Phaseolus vulgaris L.)

The effect of lead and cadmium ions on the fluctuating asymmetry of the side leaflets’ central veins of the common bean (Phaseolus vulgaris L.) was estimated. The impact of heavy metals on the parameter with the lead or cadmium content in the ground in the concentration of 650 mg/kg or 10 mg/kg respectively was not revealed.     

Prevalence of parasite eggs and cysts in faeces from dairy cows in Colombia

Summary When 1, 711 bovine faecal samples from 113 farms in eight dairy areas of Colombia were examined for the presence of helminth eggsFasciola hepatica eggs were found in the faeces from 60% of the farms and samples from animals kept above 2,000 m. Strongyle eggs were found in faeces from 82% of the farms and in 18% of the samples.

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Resumen Se examinaron 1.711 muestras fecales provenientes de 113 fincas, localizadas en ocho zonas lecheras de Colombia. Se encontraron huevos deFasciola hapatica, en el 60% de fincas y muestras fecales de animales sobre los 2,000 m.s.n.m. Se encontraron tambien huevos de estrogilideos en heces del 82% de fincas y en el 18% de las muestras examinadas.

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Résumé La recherche d’oeufs d’helminthes sur 1711 échantillons de fécès provenant de 113 fermes de 8 districts laitiers de Colombie a permis de noter la présence d’oeufs deFasciola hepatica dans 60 p. 100 des fermes et échantillons originaires d’animaux vivant à plus de 2,000 m. Des oeufs de strongles ont été notés dans les fécès provenant de 82 p. 100 des fermes et 18 p. 100 des échantillons.

     

Demonstration of uniformity of calcium absorption in adult dogs and cats

A meta‐analysis was conducted to understand quantitative aspects of calcium (Ca) and phosphorus (P) absorption in adult dogs and cats. 34 studies in dogs and 14 studies in cats met the criteria for inclusion in the meta‐analysis. Intake and faecal excretion values of Ca and P were subjected to a modified Lucas test and subsequent regression analyses. According to the current scientific consensus, Ca true digestibility (absorption) should increase at low Ca intake and decrease at high Ca intake. If true, this should result in a nonlinear relationship between the percentage of Ca excreted and dietary Ca intake. The present meta‐analysis showed a highly significant linear relationship (p < 0.0001) between Ca intake and Ca excretion suggesting a lack of systematic quantitative adaptation in true Ca digestibility. This finding suggests either that the time period covered by standard digestion trials is too short to induce adaptation mechanisms or that dogs and cats at maintenance will not efficiently alter quantitative Ca absorption percentage according to the amount ingested. If the latter is true, a dietary Ca supply differing greatly from the recommended dietary intake might impair the health of cats and dogs when fed long term. The data plots for P intake and faecal excretion were less uniform suggesting other factors not just dietary intake influence faecal P excretion. In adult cats, the dietary Ca:P ratio strongly influenced the true digestibility of P, whereas this effect was less marked in adult dogs. Faecal P excretion was significantly correlated to faecal Ca excretion in both species (p < 0.0001), and surprisingly, the level of P intake did not appear to be an important determinant of true digestibility of P.