Influences of dietary-reduced nitrogen (N) and phosphorus (P) on chemical body composition, N and P retention and health traits of contemporary barrows.

Farmgate balances are used as a tool for monitoring nutrient surpluses at farm level. In Germany, preparation of farmgate balances is legally mandatory and also requires data on chemical body composition, especially concentration of nitrogen (N) and phosphorus (P), of farm animals. It is well known that increased N and P efficiency results in lowered N and P excretions with the manure and therefore mitigates negative consequences of high N and P release into the environment (e.g. eutrophication of surface waters), especially in areas with high livestock density. In this context, feeding N- and P-reduced diets can be a strategy for increasing N and P efficiency in fattening pigs. To investigate the influence of N- and P-reduced diets on chemical body composition of barrows and to update current used data basis, 8 barrows were slaughtered after a balance trial and their bodies were subjected to full body analysis. During the balance trial, pigs received the control diet (CON) meeting common nutrient requirements or the N- and P-reduced diet (NPred) in a three-phased feeding regimen (n = 4/diet, 3 weeks/phase). Pigs were slaughtered with an average live weight (LW) of 123.3 ± 7.5 kg and carcasses were manually dissected in four fractions. Fractions were analysed for nutrient concentration. Furthermore, organs were weighed individually and blood serum was sampled during exsanguination. Serum samples were analysed for clinical-chemical traits. Chemical body composition did not significantly differ between NPred- and CON-fed pigs. N concentration was 23.3 ± 0.3 and 24.5 ± 1.0 g/kg, P concentration was 5.2 ± 0.1 and 5.5 ± 0.4 g/kg in the empty body of NPred- and CON-fed pigs (p = 0.073, 0.164). N and P retention between the experiment's start and slaughter did not differ between the feeding groups (p = 0.641, 0.240). Variables related to liver integrity, energy metabolism and electrolytes were similar between CON- and NPred-fed pigs. Traits related to protein metabolism showed significantly reduced concentrations of urea and albumin in NPred-fed pigs (p = 0.013, 0.025), but no hypoalbuminaemia. Results suggest that N- and P-reduced feeding does not significantly affect chemical body composition of contemporary barrows.

Effects of dietary-reduced nitrogen (N) and phosphorus (P) on N and P balance, retention and nutrient digestibility of contemporary fattening pigs fed ad libitum.

The reduction of nitrogen (N) and phosphorus (P) in fattening pigs' diets is one possible approach to lower N and P excretion in livestock farming relative to N and P intake. Due to the implementation of the European Nitrates Directive and the consecutive amendments to the German fertiliser legislation since 2017, N- and P-reduced diets for fattening pigs are becoming more and more important and are increasingly used in practice. To investigate the effects of such diets on N and P balance and retention as well as on nutrient digestibility of contemporary fattening pigs, a balance experiment was performed with eight barrows (average live weight = 61.5 ± 2.1 kg) which were surgically fitted with a simple T-cannula at the terminal ileum. The pigs received a control diet meeting nutrient requirements (CON) and an N- and P-reduced diet (NPred) ad libitum (n = 4/diet) in a 3-phased feeding regimen (3 weeks/phase). In the last week of each phase, faeces and urine were collected quantitatively for 5 days followed by a 2 × 12 hours collection of ileal digesta. Daily feed intake, live weight gain and feed-to-gain ratio did not differ between CON and NPred. NPred-fed pigs consumed 10.5% (p = 0.006) and excreted 28.3% (p = 0.028) less N than CON-fed pigs. Phosphorus excretion was lowered by 15.1% in NPred-fed pigs (p = 0.012). N and P retention did not differ between CON and NPred, but were elevated in comparison to other studies. N and P efficiency, expressed as nutrient retention divided by nutrient intake, was higher in NPred - than CON-fed pigs (N: 68 vs 60%, P: 54.2 vs 49.3%). Apparent post-ileal digestibility coefficient (DCpost-ileal) and apparent total tract digestibility coefficient (DCtotal) of crude protein were higher in NPred - than CON-fed pigs (p < 0.013), but apparent precaecal digestibility coefficient (DCpc) of crude protein was unaffected by diet. DCpc, DCpost-ileal and DCtotal of P were similar for CON- and NPred-fed pigs. NPred-fed pigs showed an elevated DCpc and DCtotal of organic matter, N-free-extractives and starch compared to CON-fed pigs. DCpc of calcium was also higher in NPred-fed pigs. In conclusion, the results suggest that N- and P-reduced feeding of fattening pigs remains an effective strategy to lower the N and P release into the environment. Furthermore, results indicate that N- and P-reduced feeding leads to a higher N and P efficiency in contemporary fattening pigs.

Insect Larvae Meal (Hermetia illucens) as a Sustainable Protein Source of Canine Food and Its Impacts on Nutrient Digestibility and Fecal Quality.

Insect larvae meal has been proposed as a sustainable protein source for animal diets. This study aimed to provide information on including black soldier fly larvae meal (BSFL; Hermetia illucens) in comparison to poultry meal (PM) in the canine diet with regard to digestibility and fecal characteristics. In light of this trend, the levels of PM or BSFL meal were added to replace about 30% of dry matter of the basic extruded diet. Six Beagle dogs (BW 9.64 kg) were included in a cross-over experiment. Dogs fed a BSFL meal-based diet showed higher (p < 0.05) apparent protein digestibility (82.3%) compared to those offered a PM-based diet (80.5%). Apparent digestibility for fat was higher (p < 0.05) in groups fed the BSFL meal-based diet (94.5%) compared to those offered the PM-based diet (91.6%). The fecal consistency scores for dogs fed both diets were within an acceptable range (well-formed and firm). Fecal dry matter content was higher (p < 0.05) for dogs fed the PM-based diet (33.0%) compared to those offered the BSFL meal-based diet (28.0%). Including BSFL meal in dog food can be an appropriate source of protein without any negative effects on nutrient digestibility and fecal quality.

Nitrogen output in the urban environment using a vegetarian canine diet.

Pet owners are increasingly concerned about the links between health status, animal welfare, environmental impacts, climate change and consumption of animal products. Accordingly, many owners are increasingly interested in vegetarian diets for themselves and their companion animals. However, such diets should be investigated nutritionally regards digestibility as well as on fecal quality and nitrogen output. In light of this trend, six Beagle dogs were included in a cross-over experimental design and offered a vegetarian diet containing wheat gluten (8.81%), rice protein (8.81%) and sunflower oil (6.84%) or an meat-based diet containing poultry meal (19.5%) and poultry fat (5.23%). The dogs received extruded complete diets for 12 days (adaptation and collection period, each 6 days). The dogs fed both diets showed a high and identical palatability (scoring of food intake) of the experimental diets. No significant differences occurred regarding digestibility of organic matter, crude protein and crude fat between vegetarian and meat-based diets. However, dogs fed the meat-based diet had higher (p < 0.05) nitrogen-free extract digestibility (89.5%) compared to those fed the vegetarian diet (88.6%). The amount of nitrogen excreted in feces (g)/kg BW0.75 was slightly, but not significantly, higher for dogs fed the vegetarian diet compared to those fed the meat-based diet (0.88 vs 0.79). The fecal consistency scores were considered to be within an acceptable range (well formed and firm). The mass of the feces between both groups were similar (62.9 g wet feces/100 g dry matter food) for vegetarian and meat-based diets. Additionally, the fecal dry matter content was comparable between both groups (29.0% and 29.6% for vegetarian and meat-based diets, respectively). In conclusion, the results of this study appear to indicate that virtually the only significant difference between the two diets was lower nitrogen-free extract digestibility in the vegetarian diet. However, the vegetarian diet did not result in a significant difference in amount of nitrogen excreted in feces.

[Consequences of high ambient temperatures for lactating dairy cows - an issue under practical conditions in Northern Germany?] / Auswirkungen hoher Umgebungstemperaturen auf laktierende Milchkühe ­ unter praxisüblichen Bedingungen in Norddeutschland von Bedeutung?

OBJECTIVE: The aim of the presented study was to gather quantitative data regarding the impact of high ambient temperatures on dairy cows under practical conditions in southern Lower Saxony. MATERIAL AND METHODS: In summer 2018 (from mid of July to end of September), the climatic conditions in the dairy barn as well as the temperatures of feeds (silages and partial mixed ration, PMR) and feed leftovers were recorded on the Farm for Education and Research of the University of Veterinary Medicine Hannover in Ruthe. Furthermore, daily dry matter intake (of PMR) and milk yield on herd basis as well as respiration rate and rectal temperature of 10 selected cows were measured as indicators for heat stress. RESULTS: During a heat period (daily average temperature up to 27.9° C) dry matter intake (PMR) and milk yield were reduced by about 15 % and 8 %, respectively although ambient temperatures had already been relatively high at the beginning of the observation period (daily average temperature between 19.6 and 23.0° C). Daily dry matter intake of PMR was NEGATIVELY: correlated with daily average temperature-humidity index in the barn (Spearman's correlation coefficient: -0.774, p < 0.0001) and POSITIVELY: correlated with daily milk yield (Spearman's correlation coefficient: 0.766, p < 0.0001). Correlation coefficients were slightly higher when a 1-day time lag was considered (Spearman's correlation coefficient: -0.796 and 0.800, respectively; p < 0.0001). During the heat period hyperthermia (> 39° C) was frequently recorded in lactating cows (up to 100 %). CONCLUSION AND CLINICAL RELEVANCE: The presented results indicate that heat stress in dairy cows may occur to a considerable extent under extreme climatic conditions also in the region of Northern Germany. In consequence, this is associated with a significant decrease in performance. As severe and long-lasting effects of heat stress on health and performance of dairy cows are well described in the literature, especially the temporarily high prevalence of hyperthermia should be taken seriously. Under these circumstances, differentiating between hyperthermia and fever is of special importance for veterinary practitioners.

[Feed refusal in fattening bulls because of maize silage contamination by Jimson weed (Datura stramonium)]. / Futterverweigerung bei Mastbullen durch eine Kontamination der Maissilage mit Gewöhnlichem Stechapfel (Datura stramonium).

A sudden decrease in feed intake (within 24 hours) without an impaired general condition occurred on a bull-rearing and -fattening farm in western Germany in December 2017. One day later, some of the bulls displayed signs of ruminal tympany (free gas bloat) and the reduction in feed intake became more severe. The maize silage was recognized as the cause of the observed symptoms, because clinical signs first appeared after taking the silage from a different localization within the bunker silo. Maize in this particular section was harvested from a separate area previously affected by wind damage (numerous bent maize plants), where no crop protection (herbicide application) was performed. Fruits and seeds of Jimson weed were identified in the incriminated maize silage samples. Following replacement of the contaminated parts of the maize silage with non-contaminated material and treatment of the clinically affected animals (anti-tympanic medication plus live yeast preparation), the feed intake returned to the normal level and the affected animals recovered within 6 days. The cause of the symptoms was probably the anti-nutritive properties of Datura stramonium that affect the motor function of the gastrointestinal tract.

MILK COMPOSITION OF INDIAN RHINOCEROS ( RHINOCEROS UNICORNIS) AND CHANGES OVER LACTATION.

The objective of this study was to determine the major nutrient composition of Indian rhinoceros milk ( Rhinoceros unicornis) over the first 13 mo of an 18-mo lactation period and to compare the results to those of previous studies on rhinoceros, African elephant ( Loxodonta africana), and horse milk ( Equus ferus caballus). The following parameters were measured: dry matter (DM), crude ash (ASH), crude protein (CP), ether extract (EE), nitrogen-free extract (NFE; calculated), lactose, calcium (Ca), phosphorus (P), magnesium (Mg), fatty acids (FAs), and gross energy (GE). DM, ASH, CP, and EE were determined with a proximate analysis, lactose with infrared spectroscopy and an enzymatic method, minerals with an autoanalyzer, FA with gas chromatography, and GE with bomb calorimetry. Milk samples were collected from two Indian rhinoceros cows from Zoo Basel. Rhino A gave birth to her third calf on 10 September 2012; three samples were collected and analyzed (colostrum, milk 1 wk and 2 wk postpartum). Rhino B gave birth to her eighth calf on 05 October 2013; samples were collected and 15 were chosen for the analyses (from colostrum to 13 mo postpartum). The composition of rhino B's colostrum was 13.8% DM (wet-weight basis), 4.8% ASH, 61.8% CP, 0.7% EE, 32.6% NFE, 26.7% lactose, 0.59% Ca, 0.54% P, 0.2% Mg (DM basis), and 20.3 MJ GE/kg DM. Rhino B's sample collected 13 mo postpartum averaged 8.0% DM (wet-weight basis), 3.6% ASH, 16.3% CP, 1.8% EE, 78.3% NFE, 84.7% lactose, 0.54% Ca, 0.48% P, 0.09% Mg (on DM basis), and 17.43 MJ GE/kg DM. The main FAs in rhino B's and rhino A's samples were C10 : 0, C12 : 0, C16 : 0, C18 : 1n9c, and C18 : 2n6c. Milk of the Indian rhinoceros is low in fat and protein but high in lactose, which is comparable to the milk composition of other rhinoceros species and horses, but not African elephants.

Outcome of an Experimental Study in Growing Turkeys Suspected of Having a Diet Related, Uncommon and Uncoordinated Gait.

On the occasion of a clinical case on a turkey farm and based on the suspicion that the diet composition could be the cause, an eight-week diagnostic trial was performed with turkey poults (n = 54) divided into two groups (control and experimental). The levels of vitamin A in the starter and grower diets of the control group were 7168 and 5213 IU/kg diet, but <1000 IU/kg in the experimental ones. Vitamin A and uric acid contents were measured in the serum, while liver samples were taken to determine the vitamin A content. Parts of the central nervous system and some internal organs were examined histologically. In the sixth week, ruffled feathers and uncoordinated gait were the earliest signs seen in the experimental group. The vitamin A content in the liver samples significantly decreased in the experimental group (0.09 mg/kg vs. 29.5 mg/kg). The serum level of uric acid in the experimental group was significantly higher (12.8 mg/dL vs. 3.38 mg/dL). Birds in the experimental group showed squamous metaplasia in the oesophagus. No histopathological alterations were seen in the central nervous system. The elevated uric acid level in the serum is worth mentioning.